NREL is a national laboratory of the U.S. Department of Energy

Office of Energy Efficiency & Renewable Energy

Operated by the Alliance for Sustainable Energy, LLC

This report is available at no cost from the National Renewable Energy

Laboratory (NREL) at www.nrel.gov/publications.

Contract No. DE-AC36-08GO28308

Technical Report

NREL/TP-5D00-71476

February 2019

Broadband Outdoor Radiometer 

Calibration (BORCAL) Process for the 

Atmospheric Radiation Measurement

(ARM) Program

Second Edition

Michael Dooraghi, Afshin Andreas, Mark Kutchenreiter, 

Ibrahim Reda, Martina Stoddard, Manajit Sengupta, 

and Aron Habte

National Renewable Energy Laboratory
NREL is a national laboratory of the U.S. Department of Energy

Office of Energy Efficiency & Renewable Energy

Operated by the Alliance for Sustainable Energy, LLC

This report is available at no cost from the National Renewable Energy

Laboratory (NREL) at www.nrel.gov/publications.

Contract No. DE-AC36-08GO28308

National Renewable Energy Laboratory

15013 Denver West Parkway

Golden, CO 80401

303-275-3000 • www.nrel.gov

Technical Report

NREL/TP-5D00-71476

February 2019

Broadband Outdoor Radiometer 

Calibration (BORCAL) Process for the 

Atmospheric Radiation Measurement

(ARM) Program

Second Edition

Michael Dooraghi, Afshin Andreas, Mark Kutchenreiter, 

Ibrahim Reda, Martina Stoddard, Manajit Sengupta, 

and Aron Habte

National Renewable Energy Laboratory

Suggested Citation 

Dooraghi, Michael, Afshin Andreas, Mark Kutchenreiter, Ibrahim Reda, Martina Stoddard, 

Manajit Sengupta, and Aron Habte. 2018. Broadband Outdoor Radiometer Calibration 

(BORCAL) Process for the Atmospheric Radiation Measurement (ARM) Program: Second 

Edition. Golden, CO: National Renewable Energy Laboratory. NREL/TP-5D00-71476. 

https://www.nrel.gov/docs/fy19osti/71476.pdf.
NOTICE

This work was authored by the National Renewable Energy Laboratory, operated by Alliance for Sustainable 

Energy, LLC, for the U.S. Department of Energy (DOE) under Contract No. DE-AC36-08GO28308. Funding 

provided by the U.S. Department of Energy Office of Energy Efficiency and Renewable Energy Solar Energy 

Technologies Office. The views expressed herein do not necessarily represent the views of the DOE or the U.S. 

Government.

This report is available at no cost from the National Renewable 

Energy Laboratory (NREL) at www.nrel.gov/publications.

U.S. Department of Energy (DOE) reports produced after 1991 

and a growing number of pre-1991 documents are available 

free via www.OSTI.gov.

Cover Photos by Dennis Schroeder: (clockwise, left to right) NREL 51934, NREL 45897, NREL 42160, NREL 45891, NREL 48097, 

NREL 46526.

NREL prints on paper that contains recycled content.
iii

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List of Acronyms

AIM ARM Instrument Management System

ARM Atmospheric Research Measurement Program

BMS Baseline Measurement System

BORCAL Broadband Outdoor Radiometer Calibration

ISO International Standards Organization

LW Longwave

MAS Measurement Assurance Standard

MIDC Measurement and Instrumentation Data Center

mV Millivolt

NIP Normal Incident Pyrheliometer

NPC NREL Pyrheliometer Comparison

NREL National Renewable Energy Laboratory

PIR Precision Infrared Radiometer

PSP Precision Spectral Pyranometer

RAP-DAQ Reda Afshin Pete Data Acquisition

RCC Radiometer Calibration and Characterization

RH Relative humidity

SGP RCF Southern Great Plains Radiometer Calibration 

Facility

SRRL Solar Radiation Research Laboratory

SW Shortwave
iv

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Executive Summary

The Atmospheric Radiation Measurement (ARM) program maintains a fleet of monitoring 

stations to aid improved scientific understanding of the basic physics related to the radiative 

feedback processes in the atmosphere, particularly the interactions between clouds and aerosols. 

ARM obtains continuous measurements and conducts field campaigns to provide data products 

that aid in the improvement and further development of climate models. All the measurement 

campaigns include a suite of solar measurements. The Solar Radiation Research Laboratory at 

the National Renewable Energy Laboratory supports the ARM program’s full suite of stations in 

a number of ways, including troubleshooting issues that arise as part of the data-quality reviews;

managing engineering changes to the standard setup; and providing calibration services and 

assistance to the full fleet of solar-related instruments, including pyranometers, pyrgeometers,

and pyrheliometers as well as the temperature/relative humidity probes, multimeters, and data 

acquisition systems that are used in the calibrations performed at the Southern Great Plains

Radiometer Calibration Facility. This paper discusses all aspects related to supporting the 

calibration of the instruments in the solar monitoring fleet.
v

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Table of Contents

1 Calibration Process for Radiometers, Multimeters, and Other Instruments.................................. 1

1.1 References, Controls, and Measurement Assurance Standards..................................................... 1

1.2 Digital Multimeters....................................................................................................................... 4

1.3 Temperature/Relative Humidity Probe ......................................................................................... 4

2 Pre-SGP BORCAL Channel Check...................................................................................................... 6

2.1 Channel Check Process................................................................................................................. 8

2.2 Example Order of Operations...................................................................................................... 14

3 Pre-SGP BORCAL Configuration Audit Report Checks ................................................................. 16

3.1 Outline......................................................................................................................................... 16

3.2 Create the RCC Parameters for Reference Instruments Document............................................. 16

3.3 Request a Rooftop Map from the SGP RCF Operator ................................................................ 19

3.4 Generate the Session Configuration Audit Report...................................................................... 20

3.5 Compare the Session Configuration Audit Report to the RCC Parameters for Reference 

Instruments.................................................................................................................................. 22

3.5.1 BORCAL-SW RCC Parameters for Reference Instruments.......................................... 23

3.5.2 BORCAL-LW RCC Parameters for Reference Instruments.......................................... 24

3.6 Compare the Session Configuration Audit Report to the Rooftop Layout Provided by 

the SGP Site ................................................................................................................................ 24

4 Post-SGP BORCAL Session Report Screening............................................................................... 28

4.1 Determine if Enough Data Have Been Collected........................................................................ 28

4.1.1 Concluding a BORCAL-SW Event................................................................................ 28

4.1.2 Concluding a BORCAL-LW Event ............................................................................... 28

4.2 Generate the BORCAL Report.................................................................................................... 29

4.3 Review the Full Report ............................................................................................................... 31

4.3.1 Report Review for BORCAL-SW.................................................................................. 31

4.3.2 Report Review for BORCAL-LW ................................................................................. 32

4.4 Finding the Manufacturer’s Calibration...................................................................................... 33

4.5 Editing the Sessions and Removing Outlying Data Points ......................................................... 34

4.5.1 Using Session Exclusion to Remove Data ..................................................................... 34

4.5.2 Excluding Specific Points for One or More Instruments (BORCAL-SW Only) ........... 38

5 Generate Sticker File and Stickers ................................................................................................... 42

6 Assemble All Related Documentation for Archiving at the SRRL................................................. 44

Appendix A ................................................................................................................................................ 45
vi

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List of Figures

Figure 1. The Radmin Viewer 3 icon is used to access the BORCAL ARM data processing 

computer from the SRRL......................................................................................................... 8

Figure 2. When using Radmin Viewer, choose Full Control from the Mode menu. .................................... 8

Figure 3. The RCC icon is used to run the RCC software. (It is located on a remote computer 

at the SGP.).............................................................................................................................. 8

Figure 4. Screenshot of initializing the channel check for BORCAL........................................................... 9

Figure 5. Use the “Reset Graph” function when the value is out of range to avoid plotting 

bogus averages. ...................................................................................................................... 12

Figure 6. RCC Parameters for Reference Instruments (BORCAL-SW)..................................................... 18

Figure 7. RCC Parameters for Reference Instruments (BORCAL-LW) .................................................... 19

Figure 8. BORCAL-SW tracker and table layout....................................................................................... 20

Figure 9. RCC icon ..................................................................................................................................... 20

Figure 10. Screenshot of the BORCAL configuration................................................................................ 21

Figure 11. Configuration Audit Report (BORCAL-SW)............................................................................ 21

Figure 12. The file transfer window allows the user to move the Session Configuration Audit 

Report and other files from the SGP computer to the NREL computer................................. 22

Figure 13. To conclude a BORCAL-LW event, confirm that a full range of sky conditions (mV) 

have been collected, from clear skies to overcast skies (0 mV to approximately 

-400 mV voltages). Near 0 mV are generated under cloudy conditions, and high 

negative voltages are created under clear skies. Other cloud conditions fill in the 

rest of the range...................................................................................................................... 29

Figure 14. Print the finished report to PDF from the RCC, making note that the correct mode for 

the RCC has been selected: LW or SW. ................................................................................ 29

Figure 15. Choose the radiometers for which the responsivities should be generated for the final 

report. If any radiometers were found to be unleveled or in need of quarantine, they 

can be excluded from the final report by unchecking them here. .......................................... 30

Figure 16. A potentially unleveled sensor .................................................................................................. 32

Figure 17. Accessing the BORCAL-SW radiometer inventory to note a radiometer’s manufacturer’s 

responsivity ............................................................................................................................ 33

Figure 18. Select the instrument serial number, and its value will be displayed below.............................. 34

Figure 19. Page two of the radiometer calibration report for an individual sensor shows the 

responsivity as a function of time (right) and zenith (left). The right plot (by time) 

is useful for determining which sessions to exclude and which to include............................ 35

Figure 20. The BORCAL-SW session Validity window from which sessions can be excluded (not 

checked) or included (checked) ............................................................................................. 36

Figure 21. Session exclusion window for BORCAL-LW .......................................................................... 37

Figure 22. Instrument data inclusion/exclusion window ............................................................................ 39

Figure 23. Screenshot of the minute selection ............................................................................................ 40

Figure 24. Screenshot of the global change option..................................................................................... 41

Figure 25. Main menu access to generate sticker files and create files to transfer the BORCAL 

results to the AIM Database................................................................................................... 42

Figure 26. Choose sensors and options for the AIM Database and Sticker Export .................................... 42
vii

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List of Tables

Table 1. Calibration Schedule for SGP BORCAL-SW radiometers............................................................. 3

Table 2. Calibration Schedule for SGP BORCAL-LW Radiometers........................................................... 4

Table 3. Calibration Schedule for SGP BORCAL-SW and BORCAL-LW Multimeters ............................ 4

Table 4. Calibration Schedule for SGP BORCAL Temperature/Relative Humidity Probe ......................... 5

Table 5. RAP-DAQ SW and LW Position and Channel Configuration ....................................................... 7

Table 6 RAP-DAQ SW Position and Channel Configuration .................................................................... 13

Table 7 RAP-DAQ LW Position and Channel Configuration.................................................................... 14
1

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1 Calibration Process for Radiometers, Multimeters,

and Other Instruments

Each year before the Broadband Outdoor Radiometer Calibration (BORCAL) season begins, the 

Southern Great Plains Radiometer Calibration Facility (SGP RCF) operator and the National 

Renewable Energy Laboratory (NREL) mentor at the Solar Radiation Research Laboratory 

(SRRL) should coordinate equipment to ensure that the correct multimeters, radiometers, and 

meteorological instruments are prepared for use in that year’s shortwave (SW) and longwave

(LW) BORCAL events. The following sections provide a guide to which instruments are used in 

each year’s SGP BORCAL-SW and BORCAL-LW.

BORCAL sessions are named according to where they were done (NREL or SGP), the type (SW 

or LW), the year (2018), and the calibration event number for that year. For example, SGP SW 

BORCAL 2017-02 is the second BORCAL-SW event at the SGP site for 2017. BORCAL-SWs 

are run during the summer when the sun reaches lower zenith angles (higher sun angles), 

typically from May to August. BORCAL-LWs are run at night and as a result can be performed

year-round. If the last LW BORCAL session of a year does not finish by the end of that year, it

will be named based on the year it began.

1.1 References, Controls, and Measurement Assurance Standards

Instruments used for the BORCAL-SW and BORCAL-LW events include the test radiometers 

along with a set of radiometers that are used for references, controls, and measurement assurance 

standards (MAS). BORCAL-SW and BORCAL-LW have different numbers of references, 

controls, and MAS, but the general procedure for their operation is essentially the same. Each 

year, one set of references and MAS is sent to NREL for calibration and then used the following 

year at the SGP site. That is, for both the BORCAL-SW and BORCAL-LW, two sets of 

references and MAS are exchanged each year between NREL and the SGP site and are calibrated 

at each facility. The set of control instruments is used perpetually in each event at the SGP site

and is never sent to NREL. The result of this process is that one set of instruments is calibrated at 

NREL during even years, and the other is calibrated at NREL during odd years; the same is true 

at the SGP site. Additionally, for the BORCAL-SWs, two sets of pyrgeometers are used for 

thermal corrections that are alternatively sent between NREL and the SGP site, like the 

references and MAS. The instruments described here are kept indoors when not used to 

minimize sensitivity changes due to exposure. Table 1 and Table 2 list by serial number the 

references, controls, and MAS used in the SGP BORCAL-SW and BORCAL-LW events and 

where they should be calibrated for even or odd years.

Once the SGP instruments and multimeters have been sent to the SRRL, it is necessary to verify 

against this document that the correct instruments have been sent.

The SGP BORCAL-SW includes:

• One set of control instruments. These instruments remain at the SGP site and are 

calibrated in every BORCAL-SW session. The control instruments include:

o Six precision spectral pyranometers (PSPs) 

o One normal incident pyrheliometer (NIP).
2

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• Two sets of MAS radiometers. The calibration of these instruments alternates on an 

annual schedule between the SRRL and the SGP RCF site. That is, one set is calibrated at

the SRRL, and the other is calibrated at the SGP site, and they are swapped the next year. 

The purpose of this process is to ensure consistency between the NREL and SGP 

calibrations. Note that when the radiometers are at the SGP site, they are calibrated in 

each calibration session for that BORCAL season; and when they are at the SRRL, they 

are calibrated in only one session. Each set of MAS instruments includes:

o Six PSPs 

o One NIP.

• Two reference diffuse pyranometers. These are used in combination with the direct beam 

irradiance from the cavity to calculate the reference global horizontal irradiance. Prior to 

the BORCAL-SW 2018-02 event, the reference diffuse irradiance was determined by two 

Eppley 8-48s. Beginning with the BORCAL-SW 2018-02, the reference diffuse was 

changed to two Hukseflux SR25s. Each set of diffuse instruments includes:

o Two SR25s.

• Two sets of precision infrared pyrgeometers (PIRs), which are used to correct for infrared 

losses. Each set includes:

o Two Eppley PIRs.

Note that the reference direct beam consists of two AHF Eppley absolute cavity radiometers that

are calibrated each year during the NREL Pyrheliometer Comparison (NPC). The control units 

(digital multimeters) are sent to NREL each year for calibration as described in Section 1.2.

The SGP BORCAL-LW includes:

• One control PIR

• One MAS PIR

• Two reference PIRs.
3

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Table 1. Calibration Schedule for SGP BORCAL-SW radiometers

BORCAL-SW Radiometers

Type Manufacturer Instrument SN Location

Control units to remain and SGP for all BORCAL events

Control Eppley NIP 31120E6 SGP every year

Control Eppley PSP (V) 31099F3 SGP every year

Control Eppley PSP (V) 31100F3 SGP every year

Control Eppley PSP (V) 31101F3 SGP every year

Control Eppley PSP 31152F3 SGP every year

Control Eppley PSP 31153F3 SGP every year

Control Eppley PSP 31154F3 SGP every year

Set 1 of MAS and references to be exchanged yearly between SGP and SRRL

MAS Eppley NIP 31122E6 SGP odd year/NREL even year

MAS Eppley PSP (V) 31149F3 SGP odd year/NREL even year

MAS Eppley PSP (V) 31150F3 SGP odd year/NREL even year

MAS Eppley PSP (V) 31151F3 SGP odd year/NREL even year

MAS Eppley PSP 31158F3 SGP odd year/NREL even year

MAS Eppley PSP 31159F3 SGP odd year/NREL even year

MAS Eppley PSP 31160F3 SGP odd year/NREL even year

IR correction Eppley PIR 29926F3 SGP odd year/NREL even year

IR correction Eppley PIR 30696F3 SGP odd year/NREL even year

Reference Hukseflux SR-25 2551 SGP odd year/NREL even year

(BORCAL-SW-2018-02 and after)

Reference Hukseflux SR-25 2552 SGP odd year/NREL even year

(BORCAL-SW-2018-02 and after)

Reference Eppley 8-48 33253 SGP odd year/NREL even year

(BORCAL-SW-2018-01 and before)

Reference Eppley 8-48 33273 SGP odd year/NREL even year

(BORCAL-SW-2018-01 and before)

Set 2 of MAS and references to be exchanged yearly between SGP and SRRL

MAS Eppley NIP 31121E6 SGP even year/NREL odd year

MAS Eppley PSP 31157F3 SGP even year/NREL odd year

MAS Eppley PSP 31156F3 SGP even year/NREL odd year

MAS Eppley PSP 31155F3 SGP even year/NREL odd year

MAS Eppley PSP (V) 31148F3 SGP even year/NREL odd year

MAS Eppley PSP (V) 31147F3 SGP even year/NREL odd year

MAS Eppley PSP (V) 31146F3 SGP even year/NREL odd year

IR correction Eppley PIR 30170F3 SGP even year/NREL odd year

IR correction Eppley PIR 30020F3 SGP even year/NREL odd year

Reference Hukseflux SR-25 2549 SGP even year/NREL odd year

(BORCAL-SW-2018-02 and after)

Reference Hukseflux SR-25 2550 SGP even year/NREL odd year

(BORCAL-SW-2018-02 and after)

Reference Eppley 8-48 32873 SGP even year/NREL odd year

(BORCAL-SW-2018-01 and before)

Reference Eppley 8-48 32872 SGP even year/NREL odd year

(BORCAL-SW-2018-01 and before)
4 

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Table 2. Calibration Schedule for SGP BORCAL-LW Radiometers

BORCAL-LW Radiometers

Type Eppley Instrument SN Location

Control unit to remain at SGP for all BORCAL events

Control Eppley PIR 36368F3 SGP every year

Set 1 of MAS and references to be exchanged yearly between SGP and SRRL

Reference Eppley PIR 31206F3 SGP odd year/NREL even year

Reference Eppley PIR 31237F3 SGP odd year/NREL even year

MAS Eppley PIR 30133F3 SGP odd year/NREL even year

Set 2 of MAS and references to be exchanged yearly between SGP and SRRL

Reference Eppley PIR 29927F3 SGP even year/NREL odd year

Reference Eppley PIR 29590F3 SGP even year/NREL odd year

MAS Eppley PIR 30132F3 SGP even year/NREL odd year

1.2 Digital Multimeters

Prior to each SGP BORCAL, the digital multimeters are sent to the NREL metrology lab for 

calibration. The digital multimeters need to be calibrated for use in that year’s SGP BORCAL. In 

late February, the SRRL Atmospheric Research Measurement (ARM) program mentor should 

remind the SGP Radiometer Calibration Facility (RCF) operator to send the SGP BORCAL 

multimeters for both LW and SW to NREL in early April so that they can be calibrated and 

returned to the SGP RCF on time for the first SGP BORCAL-SW event of the year. There are 

four multimeters in total; the BORCAL-SW and BORCAL-LW use the same four multimeters. 

When the multimeters have been calibrated at NREL and installed in the SGP RCF BORCAL 

and before the start of the BORCAL season, the Reda Afshin Pete Data Acquisition (RAP-DAQ) 

system channel check must be completed (described in Section 2). Table 3 lists the multimeters 

by serial number, model, and BORCAL type.

Table 3. Calibration Schedule for SGP BORCAL-SW and BORCAL-LW Multimeters

Multimeters

Manufacturer Model SN BORCAL Type

Agilent 34420A SG42000596 SW & LW

Agilent 34420A MY42002863 SW & LW

Agilent 34420A MY42002864 SW & LW

Agilent 34420A MY42002866 SW & LW

1.3 Temperature/Relative Humidity Probe

Prior to each SGP BORCAL, a temperature/relative humidity probe is sent to the NREL 

metrology lab for calibration. The temperature/relative humidity probe is calibrated at NREL for 

use in that year’s SGP BORCAL. Two Vaisala temperature/relative humidity probes are used

alternately in the SGP BORCAL from one year to another. Each year, one probe will be sent for 

calibration for use in that year’s SGP BORCAL event, and the other probe will be kept at the 

SGP site as a spare. The probe should be sent to NREL in early April for calibration along with 

the four multimeters described in Section 1.2. After calibration at NREL, the probe and meters 

will be sent back to the SGP RCF on time for the first SGP BORCAL. The probes are kept 
5

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indoors when not used. In late February, the SRRL ARM mentor should remind the SGP RCF 

operator to send the temperature/relative humidity probe (and multimeters) to NREL for 

calibration in early April. The same temperature/relative humidity probe is used for both the 

BORCAL-SW and BORCAL-LW events. Table 4 lists the temperature/relative humidity probes 

by serial number, model, and BORCAL year to be used. In 2016, the schedule swapped for the 

two probes such that E0710025 was used in 2015 and 2016, resulting in the current schedule 

shown in Table 4.

Table 4. Calibration Schedule for SGP BORCAL Temperature/Relative Humidity Probe

Temperature/Relative Humidity Probe

Manufacturer Model SN SGP BORCAL Year

Vaisala HMP 155T/H E0710026 Odd years

Vaisala HMP 155T/H E0710025 Even years
6

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2 Pre-SGP BORCAL Channel Check

Before the SGP RCF operator can connect any of the instruments to their respective channels on 

the RAP-DAQ, a channel check for all cables and connectors must be performed. Through this 

process the noise in the system is quantified by putting a short on each channel. The mV (and 

ohms on some positions) are read and recorded. This process should be done by two people: one 

person (the SGP RCF operator) is on the instrument deck at the SGP site with a short, and the 

other person (the SRRL ARM mentor) is logged into the SGP computer from the SRRL data lab

(via remote access through RAmin software). The SRRL ARM mentor calls the SGP RCF 

operator on a cell phone. The SGP RCF operator then moves the short from one position to the 

next as instructed by the SRRL ARM mentor. The SRRL ARM mentor logs onto the computer 

labeled “BORCAL ARM data processing” in the lab. Due to NREL and ARM cyber security 

requirements, this is the only computer that can be used to access the SGP BORCAL Radiometer 

Calibration and Characterization (RCC) system. The SRRL ARM mentor should be prepared 

with the Channel Check Lookup when contacting the SGP RCF operator. This chart is shown in 

Table 5.
7

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Table 5. RAP-DAQ SW and LW Position and Channel Configuration

a Note: Channel 239 is always used for the Temp probe signal, and Channel 255 is always used for the relative 

humidity (RH) signal.

PosTP Ch Pos-C Ch Pos-D Ch PosTP Ch Pos-C Ch Pos-D Ch PosTP Ch Pos-C Ch Pos-D Ch

1 48 1R 56 48 125 T9 212

2 60 49 126 T10 213

3 61 50 132 T11 214

4 0 51 133 T12 178 T12R 186

5 1 52 32 T13 192 T13R 200

6 2 53 33 T14 204

7 8 54 34 T15 226

8 9 55 113 55R 121 T16 230

9 10 56 114 56R 122 T17 236

10 49 10R 57 57 128 57R 136 T18 244

11 50 11R 58 58 129 58R 137 T19 233

12 64 12R 72 59 141 T20 234

13 65 13R 73 60 142 T21 241

14 66 14R 74 61 40 T22 193 T22R 201

15 78 62 41 T23 205

16 16 63 42 T24 237

17 17 64 130 64R 138 T25 238

18 18 65 144 65R 152 T26 245

19 80 19R 88 66 156 T27 194 T27R 202

20 92 67 149 T28 209 T28R 217

21 93 68 150 T29 242

22 4 69 157 T30 249

23 5 70 28 T31 250

24 6 71 29 T32 210 T32R 218

25 12 72 30 T33 222

26 13 73 145 73R 153 T34 246

27 14 74 146 74R 154 T35 253

28 81 28R 89 75 158 T36 254

29 82 29R 90 76 164 T5/1Vt 7 T5/1Rc 3 T5/1Rd 11

30 208 30Rc 216 30Rd 224 77 165 T5/2Vt 23 T5/2Rc 19 T5/2Rd 27

31 96 31R 104 78 166 T5/3Vt 39 T5/3Rc 35 T5/3Rd 43

32 97 32R 105 79 36 T6/1Vt 55 T6/1Rc 51 T6/1Rd 59

33 109 80 37 T6/2Vt 71 T6/2Rc 67 T6/2Rd 75

34 20 81 38 T6/3Vt 87 T6/3Rc 83 T6/3Rd 91

35 21 82 160 82R 168 T7/1Vt 103 T7/1Rc 99 T7/1Rd 107

36 22 83 232 83Rc 240 83Rd 248 T7/2Vt 119 T7/2Rc 115 T7/2Rd 123

37 98 37R 106 84 161 84R 169 T7/3Vt 135 T7/3Rc 131 T7/3Rd 139

38 110 85 162 85R 170 T8/1Vt 151 T8/1Rc 147 T8/1Rd 155

39 108 86 174 T8/2Vt 167 T8/2Rc 163 T8/2Rd 171

40 116 87 173 T8/3Vt 183 T8/3Rc 179 T8/3Rd 187

41 117 88 44 T9/1Vt 199 T9/1Rc 195 T9/1Rd 203

42 118 89 45 T9/2Vt 215 T9/2Rc 211 T9/2Rd 219

43 24 90 46 T9/3Vt 231 T9/3Rc 227 T9/3Rd 235

44 25 T3 176 T3R 184 Temp 239

45 26 T4 177 T4R 185 RH 255

46 112 46R 120 T7 225

47 124 T8 229
8

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2.1 Channel Check Process

The following steps provide a guide for performing the channel check process.

• Log in to the BORCAL ARM data processing computer in the SRRL:

o Username: rccsgp

o Password: (See SRRL ARM mentor).

• Double-click the Radmin Viewer 3 shortcut on the desktop:

Figure 1. The Radmin Viewer 3 icon is used to access the BORCAL ARM data processing

computer from the SRRL.

• Choose menu option: Mode  Full Control.

Figure 2. When using Radmin Viewer, choose Full Control from the Mode menu.

• Double-click the ARM SGP RCF RCC PC icon, and log in using the following:

o Username: sds

o Password: (See SRRL ARM mentor).

• If it is not already open, double-click the RCC icon to start the RCC:

Figure 3. The RCC icon is used to run the RCC software. (It is located on a remote computer at the

SGP.)

• Choose menu option: Acquisition  Channel Check.

• A screen will appear as shown in Figure 4. The upper left corner of the screen is used for 

initialization.

• In the past, three multimeters were dedicated to SW and 1 multimeter dedicated to LW. 

After making the upgrades to the LW process to allow for calibration of 35 pyrgeometers

at a time (as opposed to 12), all four multimeters are now used for both LW and SW 

BORCALs, and as a result, the channel check is done once each year.
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• To take advantage of the expanded LW capabilities (35 instruments as opposed to 12) it 

is necessary to use the Y-adapter cables that were built for this purpose. There are 3 types 

of adapter cables, and Appendix A shows on which positions and channels each type of 

adapter cable is used.

• BORCAL-LW and BORCAL-SW use the same four control units. Enter 4 in the box 

labeled “Unit Count.” For Units 0, 1, 2 and 3, the DVM should be set to 21, 22, 23 and 1 

respectively and the DP should be set to 24, 25, 26 and 4 respectively. The DVM for 

GPIB Boards is 0 and the DP is 1. These values are all shown in Figure 4.

Figure 4. Screenshot of initializing the channel check for BORCAL

• Select the “Init” button, circled in red in Figure 4.

• There are three graphs on the screen (shown in Figure 4). The first, at the top, is titled 

“Current Channel,” and displays the 1-second values from the chosen channel (the 

channel is chosen from the box circled in black). The second and third graphs are in the 

lower section, titled “Results by Channel,” and they display the average voltage or 

resistance for each channel when plotted by the user.

• There are two tabs for the bottom two plots shown in Figure 4, one titled Norm and one 

titled XtraTherm (grey circle).

o All voltage measurements (those that show “VDC” in the brown circle Figure 4) 

will be plotted to the “Normal” tab Voltage plot.

o The two-wire resistance measurements (those that show “RES” in the brown 

circle Figure 4) that appear on the “Normal” toggle will be plotted to the 

“Normal” tab resistance plot.
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o The two-wire resistance measurements (those that show “RES” in the brown 

circle Figure 4) that appear on the “XtraTherm” toggle will be plotted to the 

“XtraTherm” tab resistance plot.

o The four-wire resistance measurements (those that show “RES4” in the brown 

circle Figure 4) for either toggle, will not be used.

• The three buttons shown in the orange circle in Figure 4 allow the user to restart the 

graph (“Reset Graph”), pause the graph (“Pause Graph”), or plot the average value (“Plot 

Channel”) from the points on the “Current Channel” graph. The average of the values on 

the “Current Channel” graph is plotted to the associated (voltage or 1 of 2 resistance) 

plots in the “Results by Channel” section. The first value plotted is only a single point 

and cannot be seen. Two points are required to make a line that will appear in the graph. 

When the second voltage or resistance average in any of the three plots is plotted, the line

will appear.

• The top right of Figure 4 shows a toggle switch labeled “Normal” and “XtraTherm”

(green circle). For each channel, one must plot both the values using the “Normal” toggle 

and the “XtraTherm” toggle. Note that if the “Type” shown in the brown circle in Figure 

4 is “RES4”, its values will not be measured and recorded.

• As shown in the top right of Figure 4 in the black circle, the active channel number can 

be selected by either toggling the arrows or typing within the “Channel” box.

• Each channel has more than one possible purpose: it measures either voltage in mV or 

resistance in ohms or both.

• The “Current Reading” box below the channel (shown in the yellow circle in Figure 4) 

displays the millivolts or ohms of that channel. When doing the channel check, the SGP 

RCF operator will short each channel, and the displayed “Current Reading” will reflect 

that shorted channel. Shorted voltage channels typically read less than .0005 mV, and 

shorted resistance channels typically read 1 ohm to 3 ohms. Anomalous readings should 

be investigated at the time they are discovered by double-checking with the RCF operator 

for proper set up on the channel. If the anomalous reading is confirmed, it should be 

recorded and flagged for follow up.

• After selecting a channel and viewing the current readings on the “Current Channel” 

graph, if a different channel is chosen, the current channel’s values will be displayed

alongside the previously selected channel. To see only that channel’s plotted values, the 

user will need to choose “Reset Graph” after selecting the new channel.

• When the user has enough data points (only 5‒10 are needed as indicated by a limited 

range of values), click on “Plot Channel,” and the average of all the values will be plotted 

on the “Current Channel” graph. It will be plotted to the appropriate graph depending on 

whether it is a resistance channel or a voltage channel and if the “XtraTherm” toggle or 

the “Normal” toggle is chosen.

• If a point is inadvertently plotted with bogus values in its average, then the user should

collect a new set of points and plot them, and the program will overwrite the erroneous

average for that channel.
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• The SGP RCF operator has a 4-pin short for pyranometer/pyrheliometer positions and a 

10-pin short for pyrgeometer positions that they will move from one position to another. 

There may be 1-3 channels associated with each position. The SRRL ARM mentor will 

need to take readings for each channel at that position on both the “Normal” toggle and 

the “XtraTherm” toggle. Note that if the “Type” shown in the brown circle in Figure 4 is 

“RES4”, its values will not be measured and recorded. For example:

o Position 10 is associated with Channel 49 (voltage) and Channel 57 (resistance). 

When the SRRL ARM mentor finishes Position 9 and asks the SGP RCF operator 

to move to Position 10, the SRRL ARM mentor will need to measure and plot the 

values by selecting Channel 37 and plotting the results from the “Normal” tab 

(not from the XtraTherm” tab because it displays “RES4” in the type) and then by 

selecting Channel 43 and plotting the results in the same manner (channel 43 also 

is type “Res4”). Then the SRRL ARM mentor will ask the SGP RCF operator to 

move to Position 11 (which also has two channels associated with it).

o Position 61 has one channel associated with it, channel 40. Channel 40 is type 

“VDC” on the “Normal” toggle and type “RES” on the “XtraTherm” toggle so the 

SRRL ARM mentor will record measurements for both tabs. Then the SGP RCF 

operator will move to position 62 which is configured the same way.

• As shown in Table 5, if a position has only a number, then it is for either a PSP or an 8-

48. If the position has an ‘R’ associated with it, then it is a NIP or PSP. If the position has 

an ‘Rc’ or ‘Rd’ associated with it then it is a PIR (resistance of case and resistance of 

dome). If the position has a ‘T’ associated with it then it is on a tracker and is likely an 8-

48 or a NIP.

• For BORCAL-SW, 90 total positions are on the table, and 40 positions are on trackers 1 

through 4. During the channel check process, the SGP RCF operator and the SRRL ARM 

mentor will move sequentially through the table positions and then through the tracker 

positions.

• For BORCAL-LW, 15 total positions are on trackers 5 through 9. The SGP RCF operator 

and the SRRL ARM mentor will move sequentially through the tracker positions. There 

is room for an additional 24 positions using adapter cables, which allow for the SW

positions on the tables to be used for LW calibration positions. Because these cables need 

SW positions, they can be used only outside of the BORCAL-SW season. Appendix A 

shows on which positions and channels the various adapter cables can be used.

• Figure 5 shows a current reading of .00035 mV, but there was a period on the “Current 

Reading” graph when there was a reading out of range, and thus the current channel 

results are scaled to the bottom of the graph. The user should choose “Reset Graph,” 

which will fix the range issue and provide a proper set of values for averaging and 

writing to the “Results by Channel” graph.

• While Table 5 shows the positions and channels for all longwave and shortwave channels 

which aids in performing channel checks, Table 6 and Table 7 show the positions and 

channels available for SW and LW BORCALS respectively, which may be useful for 

configuration and troubleshooting. 
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Figure 5. Use the “Reset Graph” function when the value is out of range to avoid plotting bogus 

averages.
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Table 6 RAP-DAQ SW Position and Channel Configuration

PosTP Ch Pos-C Ch Pos-D Ch PosTP Ch Pos-C Ch Pos-D Ch PosTP Ch Pos-C Ch Pos-D Ch

1 48 1R 56 42 118 83 232 83Rc 240 83Rd 248

2 60 43 24 84 161 84R 169

3 61 44 25 85 162 85R 170

4 0 45 26 86 174

5 1 46 112 46R 120 87 173

6 2 47 124 88 44

7 8 48 125 89 45

8 9 49 126 90 46

9 10 50 132 T3 176 T3R 184

10 49 10R 57 51 133 T4 177 T4R 185

11 50 11R 58 52 32 T7 225

12 64 12R 72 53 33 T8 229

13 65 13R 73 54 34 T9 212

14 66 14R 74 55 113 55R 121 T10 213

15 78 56 114 56R 122 T11 214

16 16 57 128 57R 136 T12 178 T12R 186

17 17 58 129 58R 137 T13 192 T13R 200

18 18 59 141 T14 204

19 80 19R 88 60 142 T15 226

20 92 61 40 T16 230

21 93 62 41 T17 236

22 4 63 42 T18 244

23 5 64 130 64R 138 T19 233

24 6 65 144 65R 152 T20 234

25 12 66 156 T21 241

26 13 67 149 T22 193 T22R 201

27 14 68 150 T23 205

28 81 28R 89 69 157 T24 237

29 82 29R 90 70 28 T25 238

30 208 30Rc 216 30Rd 224 71 29 T26 245

31 96 31R 104 72 30 T27 194 T27R 202

32 97 32R 105 73 145 73R 153 T28 209 T28R 217

33 109 74 146 74R 154 T29 242

34 20 75 158 T30 249

35 21 76 164 T31 250

36 22 77 165 T32 210 T32R 218

37 98 37R 106 78 166 T33 222

38 110 79 36 T34 246

39 108 80 37 T35 253

40 116 81 38 T36 254

41 117 82 160 82R 168 Temp 239

RH 255
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Table 7 RAP-DAQ LW Position and Channel Configuration

2.2 Example Order of Operations

1. The SRRL ARM mentor asks the SGP RCF operator to start at Position 1 on the tables.

2. The SGP RCF operator removes the permanent short on the position, installs the 

temporary short, and tells the SRRL ARM mentor that the short is connected.

3. The SRRL ARM mentor cross-references the position to the channel per Table 5 and 

enters the channel in the “Channel” box. Note: in many cases there are multiple channels 

associated with a position and each channel must be checked on both the “Normal” and 

“XtraTherm” toggles.

4. As shown in Table 5, for Position 1 the channel is 48. The SRRL ARM mentor enters 48

into the channel box and ensures that the toggle is set to “Normal”. Because the “Type” 

(brown circle Figure 5.) shows “VDC”, the SRRL ARM mentor resets the graph (so that 

the scale is refined to the current readings), allows it to run until 5‒10 points are 

collected, and then chooses “Plot channel.”

5. Verify the result plotted in the appropriate “Results by Channel” graph at the lower part 

of the panel.

6. Move the toggle to “XtraTherm” and because the “Type” shows “RES4” the SRRL ARM 

Mentor will not record its values (only values of Type “VDC” and RES” will be 

recorded.

7. If the position also has a resistance channel associated with it (as do positions 10, 11, 12, 

13, and others), then the short stays on that position while the SRRL ARM mentor will 

enter the next channel, reset the graph, collect enough points, and plot the result. Then 

toggle to the other toggle option and repeat (unless “type” = “RES4”). If the position has

PosTP Ch Pos-C Ch Pos-D Ch PosTP Ch Pos-C Ch Pos-D Ch

1 48 1R 56 8 9 82 160 82R 168 63 42

2 60 4 0 6 2 83 232 83Rc 240 83Rd 248

3 61 5 1 7 8 84 161 84R 169 85R 170

10 49 10R 57 16 16 T5/1Vt 7 T5/1Rc 3 T5/1Rd 11

11 50 11R 58 12R 72 T5/2Vt 23 T5/2Rc 19 T5/2Rd 27

13 65 13R 73 14R 74 T5/3Vt 39 T5/3Rc 35 T5/3Rd 43

19 80 19R 88 9 10 T6/1Vt 55 T6/1Rc 51 T6/1Rd 59

28 81 28R 89 17 17 T6/2Vt 71 T6/2Rc 67 T6/2Rd 75

29 82 29R 90 18 18 T6/3Vt 87 T6/3Rc 83 T6/3Rd 91

30 208 30Rc 216 30Rd 224 T7/1Vt 103 T7/1Rc 99 T7/1Rd 107

31 96 31R 104 32R 105 T7/2Vt 119 T7/2Rc 115 T7/2Rd 123

37 98 37R 106 43 24 T7/3Vt 135 T7/3Rc 131 T7/3Rd 139

46 112 46R 120 52 32 T8/1Vt 151 T8/1Rc 147 T8/1Rd 155

55 113 55R 121 61 40 T8/2Vt 167 T8/2Rc 163 T8/2Rd 171

56 114 56R 122 62 41 T8/3Vt 183 T8/3Rc 179 T8/3Rd 187

57 128 57R 136 58R 137 T9/1Vt 199 T9/1Rc 195 T9/1Rd 203

64 130 64R 138 44 25 T9/2Vt 215 T9/2Rc 211 T9/2Rd 219

65 144 65R 152 45 26 T9/3Vt 231 T9/3Rc 227 T9/3Rd 235

73 145 73R 153 53 33 Temp 239

74 146 74R 154 54 34 RH 255
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a second resistance channel associated with it (as do 30 and 83), then the SRRL ARM 

mentor will repeat the same steps for that channel. The positions with three channels are 

used for the thermal correction pyrgeometers in the SW configuration.

8. When the voltage and any resistances associated with that position have been plotted, the 

SRRL ARM mentor instructs the SGP RCF operator to go to the next position by 

specifically telling the SGP RCF operator the position number.

9. After all the table positions are complete, the team will move on to the tracker positions

and perform the same set of steps described for the table positions.

10. When all the table and tracker positions have been checked, choose the “Save” button

(shown in Figure 4 circled in purple), and save the information to the SGP computer at 

BORCAL/System check/2018 BORCAL (with correct year). Note that the data may be 

saved at any point during the process. Further, if the channel check process for some 

reason needs to be suspended and the system shut down, the data can be saved and then 

retrieved later using the “Read” button (Figure 4 circled in purple).

11. Reminder notes:

o The BORCAL-LW and BORCAL-SW data proofs are tested as one setup.

o Be sure to check the “type” for both toggles for each channel and plot all types 

that are “VDC” and “RES” and do not record values for “type” of “RES4”.

o The 23 additional LW positions can be used only in the off-BORCAL-SW season 

(fall and winter). During the SW season, LW calibrations can be done, but only 

12 at a time using only tracker locations. This procedure assumes that the channel 

check is completed prior to the first BORCAL-SW of the season.

o Once you have completed the channel check, open the file containing the results 

for the channel check to verify that you have obtained values for all used 

channels.

o Be sure to perform both voltage and resistance checks for the positions that 

contain both.

o Once the results are saved, inform the NREL BORCAL manager to calculate the

system offsets (to be included in the Parameters for Reference Sheet).
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3 Pre-SGP BORCAL Configuration Audit Report 

Checks

Prior to each BORCAL event at the SGP site, SRRL staff will review the rooftop map and the 

RCC parameters for the reference instruments and compare them to the Session Configuration 

Audit Report, which represents what is being calibrated and their associated configurations

during that SGP BORCAL-SW and BORCAL-LW event.

3.1 Outline

Before the SGP BORCAL session begins and after the SGP RCF operator has completed the 

sensor configuration, the following procedure must be completed by the SRRL ARM mentor.

(The processes for each of these are explained in the following sections.)

• Create the RCC Parameters for Reference Instruments document. (See Section 3.2.)

• Request a rooftop map from the SGP RCF operator. (See Section 3.3.)

• Generate the Session Configuration Audit Report. (See Section 3.4.)

• Compare the Session Configuration Audit Report to the RCC Parameters for Reference 

Instruments. (See Section 3.5.)

• Compare the Session Configuration Audit Report to the Rooftop Layout provided by the

SGP. (See Section 3.6.)

• Make a folder for the BORCAL event that will contain the rooftop map, the RCC 

parameters for the reference instruments, and the Session Configuration Audit Report. It 

will also eventually contain any important email correspondences with SGP technicians, 

notes taken regarding the report, the report itself, and other related documents.

3.2 Create the RCC Parameters for Reference Instruments Document

• This document contains reference instrument serial numbers and other relevant 

information, and it needs to be updated each year. The same document will be used 

throughout the year for the various BORCAL events. There will be one RCC Parameters 

for Reference Instruments for all BORCAL-SW events in a particular year and one for all

BORCAL-LW events in a particular year, unless some unexpected change to the 

reference layout is necessary, such as the failure of a MAS or Control instrument or a 

change in the time offset.

• If this is the first event of the year, copy the NREL BORCAL RCC Parameters for 

Reference Instruments template from the following subfolder on the NREL server 

containing shared files. Choose the LW or the SW template, depending on the intent.

o NREL\SRRL\AIM\BORCAL_SGP\ARM BORCAL FILES

• Fill the empty template with the correct values for the reference instruments. These are 

obtained in the following manner:
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o Reference cavity parameters (2) (SW): Obtain the values from the NPC report 

from the previous year.1

o Reference pyrgeometers (2) (LW): Request the BORCAL results from the 

previous BORCAL event from the NREL metrology administrator or check the

ARM Instrument Management system (AIM Database). Be sure to use K0 ≠ 0 

calibration factors.

o RAP-DAQ system (SW and LW): Request the offset voltage in μV, 2-W 

resistance in ohms, and 4-wire resistance in milliohms from the metrology lab 

manager. Note: SGP wiring infrastructure currently does not support 4-wire 

resistance, so this value is not available. This value is obtained from the channel 

check described in Section 2.

o RAP-DAQ system—digital multimeters (SW and LW): Request the calibration 

date and serial number information for the four BORCAL digital multimeters

from the NREL metrology administrator.

o Pyrgeometer for NET-IR correction (SW): Request the BORCAL results from the 

previous BORCAL event from the NREL metrology administrator or obtain from

the AIM Database.

o Reference diffuse instruments (SW): Request the BORCAL results from the 

previous NREL BORCAL event from the NREL metrology administrator or 

obtain from the AIM Database.

o Metrological instruments (SW and LW): Provide the serial number and request

the calibration date from the NREL metrology administrator.

o Universal time (SW and LW): Obtain this from the current SRRL BORCAL RCC 

Parameters for Reference Instruments document located in this folder (or ask the

metrology lab manager). The latest values can also be obtained from the IERS 

Bulletin-A.2 The bulletin can also be reached from the metadata link for ΔT on 

the MIDC BMS.

• If this is not the first event of the year, reprint the RCC Parameters for Reference 

Instruments from the previous BORCAL-SW or BORCAL-LW event.

• The information is used to cross-check the Session Configuration Audit Report created 

by the SGP RCF operator.

• The RCC Parameters for Reference Instruments for BORCAL-SW will look like the 

information shown in Figure 6.

 

1 See http://www.nrel.gov/aim/npc.html. 2 See http://maia.usno.navy.mil/ser7/ser7.dat, where ΔT = 32.184 + (TAI-UTC) - ΔUT1 and ΔUT1 = DUT1.
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Figure 6. RCC Parameters for Reference Instruments (BORCAL-SW)

• The RCC Parameters for Reference Instruments for BORCAL-LW will be in the format 

shown in Figure 7.
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Figure 7. RCC Parameters for Reference Instruments (BORCAL-LW)

3.3 Request a Rooftop Map from the SGP RCF Operator

• The SGP RCF operator will either fax or email an image of the rooftop map. 

• This map shows where instruments are located (by serial number), if they are on a 

tracker, if they are ventilated, who owns the instrument, and other details.

• For BORCAL-SW, the map will be in the format shown in Figure 8.
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Figure 8. BORCAL-SW tracker and table layout 

3.4 Generate the Session Configuration Audit Report 

This section outlines the procedure for generating the Session Configuration Audit Report for the 

BORCAL-SW and BORCAL-LW events. The following screenshots illustrate these steps for a 

BORCAL-SW event. This is done after the SGP RCF operator has completed entering all the

sensors into the RCC configuration.

• Log into the SGP computer as described in Section 2.1.

• From the SGP computer, double-click the RCC icon (shown in Figure 9).

Figure 9. RCC icon

• Select the appropriate RCC event type (BORCAL-SW or BORCAL-LW). Choose the

menu option Edit  BORCAL Session, and the screen shown in Figure 10 will be 

generated.
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Figure 10. Screenshot of the BORCAL configuration 

• Check to ensure that everything on this page looks reasonable (e.g., facility name, 

BORCAL number, reference instrument serial numbers.). 

• From the BORCAL Configuration screen, choose menu option Report  Configuration 

Audit Report, and a report similar to the screenshot shown in Figure 11 will be generated.

Figure 11. Configuration Audit Report (BORCAL-SW)

• Print report by clicking Print (shown in Figure 11 circled in red).
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• Be sure to use the Bullzip PDF printer. The software will not work with other PDF 

software.

• Close all windows except for RCC. Be sure to leave RCC set to autorun for LW or SW as 

needed. 

• Use the file transfer function of Radmin Viewer 3 to move the newly printed PDF file 

from the PDF folder (on the SGP computer) to the Initial Configuration Audit folder 

which is found in both the BORCAL-SW and BORCAL-LW folders on the NREL 

computer so that it can be printed on an NREL printer. There is a folder in both the 

BORCAL-SW and BORCAL-LW folders titled “Initial Configuration Audit Reports.”

Figure 12 shows an example of the file transfer window for a 2018 BORCAL-LW event.

Note that there is a folder in both the SW and LW folders called “Initial Configuration 

Report” that is for moving this initial report.

Figure 12. The file transfer window allows the user to move the Session Configuration Audit 

Report and other files from the SGP computer to the NREL computer.

• Close all windows except for the main RCC window and log off the SGP.

• Locate the Session Configuration Audit Report that was copied onto the NREL computer

and print it to the local printer so that it can be used to compare the rooftop layout to the 

RCC Parameters for References Instruments document.

3.5 Compare the Session Configuration Audit Report to the RCC 

Parameters for Reference Instruments

Compare the reference instruments on the first two pages of the Session Configuration Audit 

Report from the SGP to the RCC Parameters for Reference Instruments document from NREL. 

The RCC Parameters for Reference Instruments will need to be created by the SRRL ARM 

mentor during the first BORCAL, and this sheet is used to check the rest of the SGP BORCALs 

that season. (This process is described in Section 3.2.) The BORCAL-SW and BORCAL-LW 

reference instruments and checks include the two following components.
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3.5.1 BORCAL-SW RCC Parameters for Reference Instruments

• Two cavity units 

o Verify that the following values match on each sheet: 

o Unwindowed and windowed World Radiometric Reference

o Unwindowed and windowed uncertainties

o Heater and heater lead resistance (This will not change from one event to 

another.)

o Manufacturer’s calibration factor (This will not change from one event to 

another.)

o Default sensitivity

o Calibration date and calibration due date

o Current shunt and circuit resistance (This will not change from one event to 

another.)

• RAP-DAQ system. Verify that the following values match on each sheet:

o Serial numbers

o Calibration date and calibration due date

o System offset volts DC

o System offset and 2-wire resistance.

• Control and MAS pyrgeometers

o Serial number

o Type (Control or MAS).

• Reference pyrgeometers for Net-IR correction. Verify that the following values match on 

each sheet:

o Calibration date and calibration due date

o K0, K1, K2, K3, Kr 

o Uncertainty

o Note that one should not use the K0 =0 values. 

• Reference diffuse instruments. Verify that the following values match on each sheet:

o Responsivity

o Calibration date and calibration due date

o Uncertainty percentage

o Offset.

• Metrological instruments. Verify that the following values match on each sheet:

o Serial number
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o Offset

o Scale

o Check that the calibration date and due date are current.

• Verify that the delta T and delta UT1 (the time corrections) are correct by crossreferencing the RCC Parameters for Reference Instruments document. 

3.5.2 BORCAL-LW RCC Parameters for Reference Instruments

• Two reference pyrgeometers

o Calibration date and calibration due date

o K0, K1, K2, K3, Kr 

o Uncertainty

o Note that one should not use the K0 =0 values. 

• RAP-DAQ system. Verify that the following values match on each sheet:

o Serial numbers

o Calibration date and calibration due date

o System offset volts DC

o System offset 2-wire resistance

o Note these RAP-DAQ values will all be the same for the LW and SW Parameters 

for Reference Instruments sheets.

• Control and MAS pyrgeometers

o Serial number

o Type (Control or MAS).

• Metrological instruments

o Serial number

o Offset

o Scale

o Check that calibration date and due date are current.

• Verify that the delta T and delta UT1 (the time corrections) are correct by crossreferencing the RCC Parameters for Reference Instruments document. 

3.6 Compare the Session Configuration Audit Report to the Rooftop 

Layout Provided by the SGP Site

First, verify that the following columns for the individual sensors are filled with correct values:

• Act: This column identifies if an instrument is active. In general, if the instrument is in 

the BORCAL, then it is active, and all should be checked “Yes.” 
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• ISO: This column identifies if the sensor is calibrated under International Standards 

Organization (ISO) standards. This is true for NREL BORCALs, but the SGP site is not 

ISO certified, so all should be marked as “No.”

• AIM:. This column indicates if the data should be stored on the AIM Database. All the 

instruments should be checked “Yes.”

• Vent: Ventilated instruments are used in the downwelling position (SKYGRD), and 

unventilated instruments are used in upwelling orientation (GNDRAD). LW is always 

ventilated.

• Sticker: This indicates whether the calibration sticker will have K0 = 0 or K ≠ 0. All test 

instruments should be “K0 = 0,” which is preferred by ARM. Note that the reference 

PIRs do use K ≠ 0.

• Use: This indicates how the instrument is used. Tot is the total or global horizontal (or 

diffuse horizontal), PYG is the pyrgeometer or longwave, and DIR is direct normal.

• Kr: This is the fourth coefficient in the series of K factors. At this time, all pyrgeometers

should be 7.044 e-4.

• Due: This is how long until the calibration is due again. All instruments should be listed 

as “12.”

Compare the locations and channels of all test and reference instruments as recorded in the 

Session Configuration Audit Report from the SGP site to the layout and inventory sheets 

(rooftop maps) provided by the SGP RCF operator. The rooftop maps contain information about

the position, channels, and owner for all instruments on the trackers and instrument tables. 

Use the following steps for each instrument for both the BORCAL-SW and BORCAL-LW. This 

is most effective when done by two people.

• Person 1 calls out a serial number from the rooftop map.

• Person 2 finds the serial number on the Session Configuration Audit Report.

• Person 1 calls out the customer, channel, and location and indicates if it is a control or 

MAS for each instrument.

• Person 2 verifies that those values match the values for the corresponding instrument on 

the Session Configuration Audit Report. A small check mark is placed by each value as it 

is verified.

• If any discrepancies are found, they should be marked and noted on the Session 

Configuration Audit Report.

• Continue this for each instrument until Person 1 has read all the instruments from the 

rooftop map.

• After all the instruments have been covered, verify that they are checked off on the 

Session Configuration Audit Report.

• Report any discrepancies to the SGP RCF operator so that they can remedy the finding 

and update the Session Configuration Audit Report.
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Notes:

• BORCAL-SW only: All pyranometers (such as model PSP ending in ‘F3’) are effective 

Net-IR corrected instrument and should also be followed by ©.

• BORCAL-SW only: Positions 37‒90 are always ventilated instruments unless otherwise 

noted and positions 1‒36 are always unventilated unless otherwise noted.

• BORCAL-SW and BORCAL-LW: If an instrument is a control instrument, it should be 

followed by ‡.

• BORCAL-SW and BORCAL-LW: The “customer” for the measurement assurance and 

control instruments is listed as “Calibration System” and should use two channels. 

• BORCAL-SW and BORCAL-LW: All instruments should have AIM set to Yes and ISO 

set to No.

• ISO must also be unchecked on the main page of the Configuration Audit Report (upper 

right, first page).

• BORCAL-LW: All instruments must be set to Use of PYG; BORCAL-SW: all 

pyranometers should be TOT, and all pyrheliometers must be DIR.

• BORCAL-LW only: The sticker should be K0 = 0, unless directed otherwise by ARM 

upper management. (Note that the reference pyrgeometers in LW events and the Net-IR 

correction pyrgeometers in SW events do not use K0 = 0).

• BORCAL-SW and BORCAL-LW: Ensure that all case and dome temperatures for MAS 

and Control instruments are configured as their appropriate types (10K for PSPs, NONE 

for NIPs).

The last pages contain the Effective Net IR corrected instruments. Here the ventilation status of 

each pyrgeometer is verified using the following steps (BORCAL-SW only):

• Person 1 reads the serial number from the unventilated table (as shown on the rooftop 

map). 

• Person 2 finds the serial number and verifies that the correcting pyrgeometer does not end 

in a V on the Session Configuration Audit Report (that is, it is not ventilated). 

• After all the unventilated instruments on the unventilated table have been covered, verify 

that there are no instruments remaining on the Session Configuration Audit Report that 

do not have a ‘V.’ For example, 29926F3 Eppley PIR-V is a ventilated pyrgeometer,

whereas 29457F3 Eppley PIR is unventilated. 

Email the SGP RCF operator to inform them of any discrepancies that were found. These include 

serial numbers that were recorded wrong or sensor channels, positions, or owners that are found 

to be wrong, etc. After the SGP RCF operator either confirms or denies the findings and any 

necessary changes have been made to the RCC configuration on the SGP computer, reprint the 

Session Configuration Audit Report and verify that the changes have been made. Discard the 

previous Session Configuration Audit Report to avoid using or archiving the wrong document. 
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After all potential discrepancies have been addressed and the updates to the RCC configuration 

have been made, inform the SGP RCF operator that the BORCAL session can begin. (Note: Print 

any important, associated email conversations with the SGP personnel, and put them into the 

folder for that BORCAL event.) As a sanity check, a test session is typically run to verify normal 

operation with no unexpected alarm conditions. Unfortunately, because LW only runs at night, 

SGP personnel do not run the test session and it is recommended that this test session be run 

through RAdmin. Keep in mind that RCC will force LW to shutdown if the user attempts to run 

a session during the daytime before solar noon. To prevent shutdown, temporarily change the 

morning shutdown zenith angle in the BORCAL system configuration to a small value such as 0 

degrees. After test session is complete, be sure to restore to the previous value (typically 94 

degrees).
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4 Post-SGP BORCAL Session Report Screening

For a BORCAL-SW event, the SGP RCF operator will inform the SRRL ARM mentor when 

they think they have collected enough data to constitute a full day’s worth of data (zenith of 70° 

and less). For a BORCAL-LW event, it is necessary for the SRRL ARM mentor to check daily 

emails (which are automatically generated through RCC) to check if enough data have been 

collected. The following sections assume that the BORCAL appears to have enough data and 

that the SRRL ARM mentor will look over the report and the data to decide whether or not the 

event can be concluded.

4.1 Determine if Enough Data Have Been Collected

4.1.1 Concluding a BORCAL-SW Event

• To conclude a BORCAL-SW event, confirm that there is clear sky for a full range of 

zenith from morning to afternoon (at least 70° to 70°). 

• This can be accomplished by combining multiple days. 

• If multiple days are combined, use the session exclusion function to choose sessions such 

that there is as little time overlap in the data as possible. Section 4.5.1.1 and Section 

4.5.1.2 describes this process. 

• If multiple days are chosen, they should be within 3-4 days of each other.

4.1.2 Concluding a BORCAL-LW Event

• To conclude a BORCAL-LW event, confirm that a full range of millivolts have been 

collected, from 0 mV to approximately -400 mV. 

• The maximum negative value will vary slightly with each radiometer. 

• It is important to get a range of sky conditions for a BORCAL-LW event. Voltages near 0 

are generated under cloudy conditions, and high negative voltages are created under clear 

skies. 

• Other cloud conditions fill in the rest of the range. Figure 13 illustrates an example of a 

full range of sky conditions.
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Figure 13. To conclude a BORCAL-LW event, confirm that a full range of sky conditions (mV) have 

been collected, from clear skies to overcast skies (0 mV to approximately -400 mV voltages). Near 

0 mV are generated under cloudy conditions, and high negative voltages are created under clear 

skies. Other cloud conditions fill in the rest of the range.

4.2 Generate the BORCAL Report

If it is determined that the reference sky conditions are sufficient to conclude the BORCAL

event, the results need to be further scrutinized. This involves printing and reviewing the results 

as follows. 

• To view a report, log onto the SGP computer, open the RCC, and choose menu option 

Generate  Responsivities. (Make sure that the toggle switch is set to the type of 

BORCAL of interest: LW or SW). See the following figure.

Figure 14. Print the finished report to PDF from the RCC, making note that the correct mode for

the RCC has been selected: LW or SW.

• The window shown in Figure 15 will appear after selecting the menu option to generate 

responsivities. Ensure that all instruments are checked, the correct BORCAL event has 

been selected, and that the RSR filter is set to blue. Once “Generate” has been selected, 
30

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the process will take approximately 10 minutes for a full BORCAL-SW and a shorter 

time for a BORCAL-LW event.

Figure 15. Choose the radiometers for which the responsivities should be generated for the final 

report. If any radiometers were found to be unleveled or in need of quarantine, they can be 

excluded from the final report by unchecking them here.

• Then choose menu option Generate  Report  Instrument Results  by BORCAL

• Examine approximately 10 instrument reports to confirm that 

o The dates are correct

o There are no extreme outliers

o The recent responsivity does not deviate too far from historical responsivities. 

• If the report looks good upon preliminary viewing, contact the SGP RCF operator to let 

them know that they can cease the BORCAL watch procedures. No instruments should 

be removed yet, but the watch can stop. This affects only the BORCAL-SW event 

because the BORCAL-LW event is unmanned and can continue automatically.

• Move all files associated with that event from the SGP computer to the NREL computer 

where the final report will be generated and examined. This is described in the following. 

a. The first step is to log onto the SRRL computer to access the SGP computer and 

run “Radmin Viewer 3.”

b. Choose the file transfer option of Radmin Viewer 3 to reveal two Explorer-style 

windows with the local computer on the left and the SGP remote computer on the 

right. To transfer files, drag the files from the right (remote computer) to the left 

(local computer). 

c. On the remote computer navigate to C:\Borcal\DB, and on the local computer 

navigate to D:\SGP\DB. Find the file titled rcc.mdb. Drag the rcc.mdb file from 

the remote computer to the local computer. The transfer will take a couple of 
31

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minutes. It may be necessary to change the name of the previous RCC database 

on the NREL computer file so as not to overwrite it. 

d. On the remote computer navigate to C:\Borcal\Data_SW\ 2015-02\, and on the 

local computer navigate to D:\SGP\Data_SW \2015-02\. (Use the correct year and 

BORCAL event and BORCAL type: LW or SW.)

e. Copy the contents of all of the folders from the remote computer to the local 

computer by dragging the folders from one to the other.

f. Log off the SGP computer and close the screen.

• After this prescreening, generate the full report as a PDF on the NREL computer; do not 

print a paper copy. To do this, use the following toolbar access on the RCC: Generate 

Report  Full Report. Be sure to choose Bullzip to generate the report and not Foxit or 

any other PDF creator. 

4.3 Review the Full Report

The next step is to look at the whole report, including each instrument’s sub-report. The full 

report begins with the control instruments and the results summary, followed by each 

instrument’s individual calibration certificate. The processes for BORCAL-SW and BORCALLW are different from each other, and they are described in the following two sections. 

4.3.1 Report Review for BORCAL-SW

• Control instruments

o All control instruments should be <1% deviation from the most recent historical 

responsivity and track other similar control instruments. 

• Environmental and sky condition plots summary 

o This is at the end of the report, and all plots should be verified as complete and 

reasonable. Also, verify that there is continuous solar data from morning to 

evening (<70° zenith).

• Calibration certificate for each sensor

o Verify that the calibration date and next due date is correct. 

o Verify that there are no outliers. If there are, note the serial number of the sensor 

and the approximate time of the outlier. This will help filter those outliers later. 

Outliers only need to be removed when they are so far off the scale that the other 

data are made indistinguishable due to the large scaling of the graph. Section 

4.5.1.2 describes this process.

o Verify that the responsivity compared to the zenith is symmetric (that is, that the 

a.m. and p.m. values are not too far off from each other). If it is not symmetric, a 

sensor might be out of level. Following is an example of a potentially unleveled 

sensor that should be marked for physical inspection by the SGP BORCAL team 

to determine if it is not level, there are blemishes on the dome, a radiation shield

that is not properly seated, graying of the sensor, etc.
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Figure 16. A potentially unleveled sensor

o Note that in most instances fitting the description in the previous point, the sensor 

will be level and the misalignment of the morning and afternoon zenith data is a 

true representation of that sensor’s responsivity. This is a main reason for the need 

to calibrate thermopile sensors with their cables pointing to the north.

o Verify that from a historical standpoint the recent responsivity does not vary too 

much from the last responsivity. Generally, the percent change from the last 

BORCAL should be within the uncertainty of the instrument.

• Provide the SGP RCF operator with a list of serial numbers for the sensors that are

believed to be unleveled or otherwise questionable so that the offending radiometers can 

be checked. If sensors are found to be unleveled or damaged, the SGP RCF operator will 

need to re-level and run it in the next BORCAL or put it into quarantine.

• After all the outliers, historical deviations, and potentially unleveled sensors have been 

noted, it is time to remove the outliers. This is described in Section 4.5.

• If an instrument is found to have a bad calibration, it can be removed from the final report 

results by the following menu option: Edit  Database  Calibration Data. Then find 

the instrument by serial number and choose edit. Then change “Valid” to “Invalid.”

4.3.2 Report Review for BORCAL-LW

• Control instruments

o The control instruments for BORCAL-LW will have four K coefficients 

associated with them as determined from the calibration. The four coefficients 

should follow these general guidelines:

̶ K0: Ranges from 4 to -16 W/m2

̶ K1: Ranges from 0.19 to 0.38 W/m2

̶ K2: Ranges from 0.994 to 1.041 W/m2

̶ K3: Ranges from -2.4 to -6.4 W/m2

.

• Environmental and sky condition plots summary 
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o This is at the end of the report, and all plots should be verified as complete and 

reasonable. 

• Calibration certificate for each sensor

o Verify that the calibration date and next due date is correct. 

o Verify that the residuals for the calculated BORCAL-LW for that instrument 

compared to the reference have two standard deviation bounds that are within ± 1 

W/m2

.

o Verify that the uncertainty falls below 2 W/m2 ‒ 3 W/m2.

o Review the residual plots for each sensor (these are stored in 

DATAFILES\CALDAT folder for the BORCAL and are emailed daily during a 

given LW event). Sensors that have been calibrated before should have small 

residuals (less than approximately ± 4 W/m2) for all voltages when using the old 

coefficients. If it is a sensor’s first outdoor LW calibration then the residuals will 

form a line with a slope and the values of the points should not lie more that ± 4

W/m2 from that line.

4.4 Finding the Manufacturer’s Calibration 

Note that for any sensors that are in their first BOCAL and thus do not have a previous 

BORCAL calibration value to compare to, the manufacturer’s calibration value can be used. 

Following are the steps for finding the manufacturer’s calibration value.

• From the RCC SGP software, choose Edit  Database  Radiometer Inventory

(Pyrgeometer Inventory for BORCAL-LW).

Figure 17. Accessing the BORCAL-SW radiometer inventory to note a radiometer’s manufacturer’s 

responsivity
34

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• The screen shown in Figure 18 will appear.

Figure 18. Select the instrument serial number, and its value will be displayed below.

• Find the radiometer in question by typing its serial number, then note the manufacturer’s 

responsivity for that sensor.

4.5 Editing the Sessions and Removing Outlying Data Points

There are two basic methods to remove or include data from the responsivity calculations:

session validity and data exclusion. Use session validity to make large global changes to the 

sessions that are available for use in the responsivity calculations. This is commonly used to 

exclude sessions with poor data quality and clear sessions that might overlap other clear sessions 

on other days. Use data exclusion to remove individual outliers in the data for a single instrument 

or for a group of instruments within a short time period.

4.5.1 Using Session Exclusion to Remove Data

A BORCAL-SW session consists of a few hours of data or less and might be kept or excluded 

depending on the clearness and the stability of the sky during the session. BORCAL-LW is 

different in that a session runs all night long. Full sessions can be excluded for both BORCALSW and BORCAL-LW, and the processes are similar for both and discussed in the following two 

sections.

4.5.1.1 Using Session Exclusion to Remove Data for BORCAL-SW

• The goal is to find a full day’s worth of good data (a full zenith range from morning to 

afternoon of clear, stable sky conditions). During some BORCAL events, all the data will 

be gathered during a single day. More often, however, data might be used from one

morning one day and an afternoon from another or data from three or even more days

might be combined. When combining days, there should not be data from the same time 

of day overlapping each other from different days.
35

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• Open report for any sensor using the following: Generate → Report → Instrument 

Results → by BORCAL.

• Pick one of the sensors (preferably a PSP because the responsivity curve has a regular 

shape to it) and click Generate.

• This action will generate a report for the individual sensor. On page two of this report,

two graphs show responsivity as a function of time (right) and as a function of zenith 

(left). These are shown in Figure 19. For this process, the graph on the right is the one of 

interest: it shows the responsivity as a function of time. Figure 19 shows a calibration 

report for an individual sensor with no data excluded. There are three days’ worth of data 

represented in the Responsivity vs. Local Standard Time graph in Figure 19: one is 

shown in red, one in blue, and one in green. Each day will have a separate color.

Figure 19. Page two of the radiometer calibration report for an individual sensor shows the 

responsivity as a function of time (right) and zenith (left). The right plot (by time) is useful for 

determining which sessions to exclude and which to include.
36

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• Because the day that is represented by red is so short, is not a smooth function, and is 

otherwise occurring during the same time of the day as the blue day, the red data can be 

excluded. Likewise, most of the green or blue day data can be excluded to obtain as much 

of a full day as possible.

• By clicking on any of the points on the graph, the date and time that the data occurred

will be displayed. The red data shown in Figure 19 above is from July 12, the green data 

is from July 13, and the blue data is from July 14. This example uses the evening of July 

13 and all of July 14.

• Open the session Validity window by using the following: Edit → Session Validity. 

Figure 20 shows this window. By clicking the corresponding session numbers, the data 

are limited to the days and times discussed above.

Figure 20. The BORCAL-SW session Validity window from which sessions can be excluded (not 

checked) or included (checked)

• At this point, review the valid session selection by regenerating the responsivities and 

subsequently the instrument report and observing whether the changes occurred as 

expected—that is, there is one continuous set of data covering morning and afternoon 

from at least 70°.
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4.5.1.2 Using Session Exclusion to Remove Data for BORCAL-LW

The process for excluding sessions for BORCAL-LW is very similar to the process for 

BORCAL-SW. The main differences are the time frame that a session represents and the reason 

for excluding a session. A session in BORCAL-LW lasts the full night; there is a session for each 

night. A session should be excluded if it rained that night or was extremely dusty or windy. 

Because the event occurs at night, many times the conditions might not be known and another 

source of data will need to be used to determine wind speeds or rain. Figure 21 illustrates a 

session exclusion screen for BORCAL-LW. Note that each session represents a full day.

Figure 21. Session exclusion window for BORCAL-LW
38

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4.5.2 Excluding Specific Points for One or More Instruments (BORCAL-SW Only)

In some instances, specific data points might be removed from the valid data range (instead of a 

full session’s worth of data). Examples include:

• When the graph of the responsivity is squished because of a data point that is out of 

range, specific points for one or some instruments might be excluded.

• If a small cloud passes over the sun disc and causes a blip in the data for all instruments,

data during that event might be excluded by applying a global change to a set of data.

(Note that even though this affects all sensors, it is not equivalent to a session exclusion 

because it occurs during a short, limited time.)

When one or more outliers in the data have been noted, these can be removed from all reports by 

using the RCC Data Inclusion/Exclusion function. Care should be taken when editing data within 

±0.3° of 45° zenith angle, as removal of such data can prevent responsivity generation.

• First, note the exact date and time of the outliers. Open the report for any sensor using the 

following RCC toolbar access: Generate  Report  Instrument Results  by 

BORCAL. Pick one of the sensors and click Generate.

• When the report is generated, choose page two of the report and click on the outlier(s) in 

the Responsivity vs. Standard Time graph. Note the date, approximate time, and 

responsivity of the point.

• Use the following toolbar access: Edit  Data Inclusion/Exclusion. This will open a 

window containing a grid of squares with sensor serial numbers on the Y axis and hours

on the X axis (Figure 22). Double-click the square corresponding to the serial number 

and hour in question.
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Figure 22. Instrument data inclusion/exclusion window

• A new zoom screen will open with another grid of squares representing the hour chosen 

(Figure 23). The minute is on the Y axis. The X axis contains two columns: one for the 

first half minute and one for the second half minute. Choose the square or group of 

squares that contain the time of the data in question.
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Figure 23. Screenshot of the minute selection

• On the right side of the screen is a list of boxes titled “Apply to Selection.” Here 

individual flags or all flags can be removed depending on the need. For outlying data 

points, check the box for “Exclude All Data,” and click “Apply.”

• Save and exit. 

• Follow the above steps for each sensor that contains an outlier.

• To make a global change to the data set, click “Chk All” button” or individually click all 

the boxes corresponding to the sensors that should be changed. Then click the Global 

Change Button (see Figure 22). Pick the time and date, check “Exclude All Data,” and

click “Apply.” To capture all scan groups, remove all data around the outlier for the full 

30-second block.
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Figure 24. Screenshot of the global change option

• To write the changes to the database, use the following toolbar access: Generate 

Responsivities.

• To check that the point has been removed, generate an instrument report (Generate 

Report  Instrument Results  by BORCAL), and check the second page to verify that 

the point or points are missing.

• Finally, regenerate the full report so that it contains the changes made using the following 

toolbar access: Generate  Report  Full Report. Check that the default values for the 

front page of the report are correct.

• Thoroughly review the whole report page by page, as described in Section 4.3. 
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5 Generate Sticker File and Stickers

After the report has been reviewed by the technical manager, the files and data have been 

transferred to the NREL SGP computer, and responsivities and full report have been regenerated, 

generate the stickers that will be sent to the SGP RCF operator to be affixed to each instrument. 

This process will also generate the report and data files The AIM Database will need to be 

updated with that BORCAL event’s report and data.

• From the RCC software on the NREL SGP data-processing computer, ensure that the 

appropriate BORCAL event type is selected (SW or LW), then choose File  Export 

AIM Calibration Stickers.

Figure 25. Main menu access to generate sticker files and create files to transfer the BORCAL 

results to the AIM Database

• This will generate the screen shown in Figure 26.

Figure 26. Choose sensors and options for the AIM Database and Sticker Export
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• Choose “Check All” unless some instrument calibrations were determined to be bad, in 

which case you would not check those instruments.

• Ensure that both of the following boxes are checked:

o FileMaker Pro AIM Export

o LabelRIGHT Sticker Export.

• Click the filename box and change the default filenames to SGP_LW-2015-02 (using the 

date and BORCAL event number and type matching the current BORCAL).

• Choose Export.

• This will generate two files (SGP_2015-02.aim.csv and SGP_2015_02.lbl.txt) in the 

following directory: D:\SGP\Data\2015-02\Export.

• Send these two files to the NREL AIM Database administrator, the NREL metrology 

administrator, and the SGP RCF operator. Request that the NREL metrology 

administrator print the sticker file (*.lbl.txt), request a spot check for accuracy after 

printing, and mail them to the SGP RCF operator for placement on the sensors.

• The *.AIM.csv file will be used by the NREL AIM Database administrator to import the 

calibration results into the AIM Database.

• Note: For BORCAL-SW, there are various data files (such as 2-degree RS export files)

that are automatically transferred to the NREL AIM public website so that they can be 

accessed via web browser after the NREL AIM Database administrator imports the 

*.AIM.csv file into the database.
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6 Assemble All Related Documentation for Archiving 

at the SRRL

Assemble a folder of materials to be archived at the SRRL. The folder should contain:

• Black-and-white copy of the SGP BORCAL report (optional)

• Notable findings and all notes regarding the quality-check process

• BORCAL Report QC Checklist

• Session Configuration Audit Report 

• RCC Parameters for Reference Instruments

Rooftop map.
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Appendix A

Channel Assignments for Dual Connector with Dome using Pins A & B

Cable TP/Case 

Position

TP 

Channel

Case 

Channel

Dome 

Position

Dome 

Channel

1 37 98 106 43 24

2 64 130 138 44 25

3 65 144 152 45 26

4 46 112 120 52 32

5 73 145 153 53 33

6 74 146 154 54 34

7 55 113 121 61 40

8 56 114 122 62 41

9 82 160 168 63 42

10 1 48 56 8 9

11 19 80 88 9 10

12 10 49 57 16 16

13 28 81 89 17 17

14 29 82 90 18 18

Channel Assignments for Dual Connector with Dome using Pins C & D

Cable TP/Case 

Position TP Channel Case Channel

Dome 

Position

Dome 

Channel

1 57 128 136 58 137

2 84 161 169 85 170

3 11 50 58 12 72

4 13 65 73 14 74

5 31 96 104 32 105

Channel Assignments for Triple Connector using Pins A & B for each Position

Cable TP 

Position

TP 

Channel

Case 

Position

Case 

Channel

Dome 

Position

Dome 

Channel

1 2 60 4 0 6 2

2 3 61 5 1 7 8
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BORCAL Report QC Checklist

BORCAL ____________

(Initial each step)

Cover Page

___ Verify BORCAL event number

___ Verify correct calibration facility

___ Verity dates for calibration and report

___ Disclaimer notice (inside front cover)

Introduction

___ Introductory notes, when entered, are present.

Reference and Meteorological Data Plots

___ Reference irradiance is reasonable (Note: Separate page for tilt) 

___ Met plots present and reasonable

___ Means reasonable and consistent with data

Control Histories Page

___ Current results consistent with instrument histories

Results Summary

___ All responsivities look reasonable

___ All uncertainties look reasonable

___ Spot-check page numbers (first, middle sample, last)

___ Ancillary data page number

Certificates

___ Reference cavity ID, calibration and due dates (check once)

___ Reference diffuse ID, calibration and due dates (check once)

___ Calibration date and due date correct (check once)

___ Data acquisition dates correct (check once)

___ Technician names okay (check once)

___ Instrument naming convention (s/n, mfgr, model, spelling)

___ Customer matches customer in results summary

___ Data plots free of outliers

___ Instrument history consistent with past calibrations

BORCAL Notes 

___ Notes, when entered, are present with correct grammar/spelling

Configuration Audit

___ All fields present and reasonable (not present in customer report)

Operator Session Logs

___ Present (not present in customer report)

Signatures

___ Technical manager

Stickers and AIM Database

___ Results summary compared to incoming instrument checklist

___ Sticker file compared to RCC database

___ Stickers generated and affixed to instruments

___ AIM Database updated

BORCAL web page updated

___ Full Report (PDF file)

___ Refence Irradiance (Text file)

Distribution and Archive

___ Certificate sent with all instruments

___ Customer reports sent as requested

___ Full report archived