NBS

'UBLICATIONS A 11 ID 2 B3113E

NAT’!. INST OF STANDARDS & TECH R.I.C.

Instructions

J. B. Fowler

B. J. Belzer

U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Center for Radiation Research

Radiometric Physics Division

Gaithersburg, MD 20899

December 1986

U.S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

QC

100

• U56

86-3477

1986

c.2

MBS

RESEARCH

INFORMATIOM CENTER Al£66-

NBSIR 86-3477

WATER BATH BLACK BODY OPERATING

INSTRUCTIONS

J. B. Fowler

B. J. Belzer

U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Center for Radiation Research

Radiometric Physics Division

Gaithersburg, MD 20899

December 1986

U.S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary

NATIONAL BUREAU OF STANDARDS, Ernest Ambler. Director

WATER BATH BLACK BODY OPERATING INSTRUCTIONS

Joel B. Fowler

and

Barbara J. Belzer

National Bureau of Standards

Gaithersburg, Maryland 20899

Table of Contents

I . Hardware

A. Constant Current Source

B. Equipment Hook-up

C. Water Bath Setup

II. Filling the Bath Cavity

III. Turn On Procedure

IV. Computer and Program Operations

A. Booting Up

B. Accessing the Control Program

C. Using the Program

D. Stopping the Program

E. Data File Access

F. Shutting Down the System

V. Notes

VI. Equipment List

VII. Figure 1. Cutaway view of the water bath

VIII. Figure 2. Cable connection diagrams

IX. Figure 3. Water Bath control panel.

X. Appendix 1: a) Constant current source

b) Four wire thermistor

c) Digital voltmeter (DVM)

d) Digital-to analog converter (DAC)

Appendix 2: Control computer

1
WATER BATH BLACK BODY OPERATING INSTRUCTIONS

Introduction

The Water Bath Blackbody is an instrument designed and built

for use in the 5 to 60 degree Celsius temperature range with an aperture of approximately 10.8 cm. Measurements have indicated

that the temperature is uniform to better than +/- 15 mK.

Details on the conceptual design and testing the the water bath

blackbody are described in a companion report written by Jon

Geist and Joel Fowler. [1]

This manual contains instructions for setting up the water

bath blackbody and associated hardware and instructions for

operating the instrument.

I

.

Hardware

<Refer to page 8 for a listing of the hardware provided>

A. Constant Current Source

First, a note regarding the constant current source: In

order for the current source to completely stabilize, it

must be turned on and allowed to stabilize for a period of

approximately 24 hours. After it has warmed up it SHOULD

NOT BE turned off again. All operating connections can be

made with the power on.

B. Equipment Connections

1. Connect the computer to any 120 VAC outlet.

(The monitor can be connected to the outlet at the back

of the computer.)

2. Connect the DVM to any 120 VAC outlet and connect the

IEEE cable from it to the output of the GPIB Card on the

back of the computer. (The cable is provided)

3. Connect the printer cable (provided) from the printer

to the parallel port on the back of the computer.

C. Water Bath Setup

-Refer to Figure 1, page 9-

1. Make sure the Baffle (Fig. 1) is in place and the

tubing is connected to the nozzle.

2. Place the N-4 Module on the bath and attach with the

two mounting screws on the stainless steel plate.

2
3. Place the Control Head on top of the N-4 Module.

- Refer to Figure 2, page 10-

4. Make the following cable connections:

a. The Remote Temperature Control Cable has a 5 -pin

Male Connector at one end and a Triax connector at the

other. Connect the 5-pin connector to Socket 1 on the

back of the Control Head and the Triax connector to the

Triax socket on the back of the computer.

b. Connect the Flat Cable from the N-4 Module to the

25-pin socket (4) on the Control Head

c. Connect the Power Cable of the N-4 Module to the

Socket on the rear of the Bath.

d. Connect the 6-pin Control Cable to the socket of the

N-4 Module and its mate on the Bath.

e. Connect the Main Power cable to 220 VAC.

-SWITCH THE CONTROL HEAD POWER SWITCH TO OFFf. Switch the on/off switch on the back of the Bath to

the '1' position. (On)

II . Filling the Bath Cavity

A. Pour the contents of one 12 oz. bottle of Anti-Rust and

Water Pump Lubricant in the cavity chamber.

B. Fill the chamber with tap water until the level

indicator of the N-4 module shows a reading of about 9.

This should be somewhere very near the indentation of

the cavity chamber. Overfilling will cause the bath to

overflow when operated and underfilling will set off the

alarm.

NOTE: If you are operating the bath at the higher temperature

ranges over a period of days, check the level of the water on

a regular basis as the water will tend to evaporate.

C. Turn on the bath and allow the solution to mix for a minute or so. Turn off and continue connection procedure.

D. Place the styrofoam cover on the cavity and insert the

thermistor to the proper height, (where the

teflon seats into the styrofoam.

)

E. Connect the Thermistor wires as follows:

3
-Note: the labels are stamped on the connector lugsOne each of the two lugs marked #1 are connected to the

Red(+) jack of the constant current source and the DVM

Hi (top) Input on the DVM. One each of the two lugs

marked #2 are connected to the Black (-) jack of the

constant current source and the DVM Lo (middle) Input

on the DVM

.

The fifth wire of the four wire thermistor is the shield

and is stamped G on the lug. Connect this to the bottom

connector on the DVM, which is marked 'I' and is to the

right of the fuse.

Ill . Turn On Procedure

-Refer to the Control Panel Diagram, Fig. 3, page 11-

A. Turn on the water bath with the switch located at

the upper left hand corner of the control panel. The

green indicator light should come on.

B. If the bath is on 'EXT', indicated by the amber

indicator, it should be switched via that button to

' Internal .

<The 'EXT' switch is located directly beneath the on/off

switch >

NOTE: The internal temperature has been preset to 22-25 deg. C. The control head stores this information for up to 12 months even when the power is off. The over- temperature , alarm condition

parameter has been preset to 70 deg. C. and also is stored by

the control head.

IV. Computer and Program Operations

A. Booting Up

1. Switch the computer on

(The power on switch for the computer is located on

the back of the unit in the upper right corner)

2. The programs necessary to operate the Water Bath

Black Body are resident on the hard disk.

3. The monitor will initially ask the user:

TEST MEM (Y/N)

-The system will default to 'N' after a short delay. You can hasten the system bootstrap slightly by typing an 'N'.-

- After booting up, you will be asked to set the date and the time.

4
After these are set, the computer will display the prompt:

"C:\wb>" on the screen.

-This indicates that you are in the correct directory for the

water bath temperature control program.

B. Accessing the Control Program

There are two ways to get into the temperature control program:

1. Following the prompt, type "Tbasic"

C :\wb>Tbasic

-Once the program is loaded, the prompt will appear as -> When this prompt appears, respond as follows:

->old"ctemp . sav"

->run

(NOTE: "old" is Tbasic command for "Load" and "ctemp.sav is the

temperature control program.

)

2. To simplify loading, you may just type:

C:\wb>tbasic ctemp.sav

C. Using the Program

Follow the instructions on the monitor as in the following

example

INPUT FILENAME<data filename ... something

other than ctemp.sav; i.e: Testl.001>

-at this point, you may select one of four options

pertaining to the data you wish printed to your fileWhat data do you want in your file?

(1) stable data only - S (2) unstable data only = U

(3) both = B

(4) none = N

?

-type in the letter corresponding to your selection. After

a brief delay, the program will respond with the current

temperature of the bathCurrent Temp, is Ccurrent temperature>

Please input maximum dt (eg.. 01 = lOmK)

<Input the maximum desired Delta T, i.e. :0. 015

for 15mK>

INPUT SETPOINT Cinput the temperature value

at which you wish the bath to operate.

DO NOT follow the value

5
with "deg. C" , just the number, ie

:

60.00 for 60 deg. C>

Switch water bath to "EXT" , then hit any key

<" EXT" is located just below the power switch

on the water bath control panel

(the temperature display on the bath head

should blank out and the 'EXT." light should

come on) then hit any key on the computer

keyboard>

?Changing Temperature

-The computer is now monitoring the temperature of the water

bath and will display the temperature and the difference from the

setpoint. When the bath gets near the setpoint, the computer

will display this and keep you apprised of the stability of the

bath as well

.

- Once the temperature becomes stable (see Note 1 below)

,

proceed with your measurements.

D. Stopping the Program

1. The program is in a loop that is necessary for it

to control the water bath to your setpoint. If you wish

to change your setpoint or shut down the system, proceed

as follows:

2. Ctrl C will give you an error stop and then

the computer will beep. <' Ctrl' and 'C' must be typed

s imul t aneous ly .

>

3. The monitor will display the prompt,

4. To restart the program (the program will not

default to your previous parameters, all values must be

reset whether you are changing them or not) type RUN

5. To terminate the program and Tbasic, set the water bath

to internal and type QUIT

E. Data File Access

1. If you wish a hardcopy of the information being

displayed on the monitor during the time the water bath

is in operation, simply enter a CTRL P as you initiate

the run. You can stop the print out at any time by

entering another CTRL P

2. To examine the data files you have created, you must

be out of TBasic. That is, you have exited the

temperature control program with a CTRL C . typed 'Quit'

in response to the prompt ->, and are seeing the prompt

6
C:\wb on the screen.

a. Typing dir following the prompt will list the

files in the wb directory. The names, dates, and

times your input files were created will be displayed.

b. To look at a data file, enter type <filename>

after the prompt. Again, for a hardcopy of the

information, enter a CTRL P before using the CR after

the filename

F. Shutting Down the System

1. Stop the program and 'quit' Tbasic.

2 . Turn off the power to the computer and the water

bath (using the switch located on the Control Head) in

any order.

REMEMBER: DO NOT TURN OFF THE CURRENT SOURCE ?

NOTES

Note 1. - The stability of the water bath black body is

dependent upon two factors. First, the ambient temperature will

have an effect on the stability. If the operating temperature

(setpoint) is close to the room temperature, it will be more difficult to maintain. Secondly, the heating system is more powerful than the cooling system. As a result, while the bath

may take a relatively long time to reach stable condition at

higher setpoint levels (30 - 60 deg. C) , the duration of the

stable condition will be longer than the duration of the stable

condition at the lower setpoints (0 - -25 deg. C) . However, the

bath wil remain stable at the lower temperatures for a sufficient

time for completing any measurements easily.

Note 2. -Alarm conditionsAn audible and visual alarm will begin and the pump will shut

down if the water temperature reaches the preset parameter or if

the water level becomes too low. The alarm can be shut off by

means of the 'Alarm Release Switch' which is visible only during

alarm conditions.

Reference

[1] "Water bath black body", J. Geist and J. Fowler (to be

published)

7
EQUIPMENT LIST

* Olympia NP Printer

* Columbia Personal Computer & Keyboard

* Amdek Video-300 Monitor

* Hewlett-Packard 3457A Digital Voltmeter

* Constant Current Source

* Thermometries Thermistor

* Haake N-4R incl.:

control head

N-4 module

Bath

* Hook-up cables for all units

* Equipment Manuals

* Columbia Software

This equipment list is not an endorsement, either expressed

or implied, of any of the commercially available equipment

noted herein.
Control Head

Flow

Nozzle

Cavity

Chamber

Black

Body

Cavity

N-4 Module

Baffle

Cooling

Coils

Hose

FIGURE 1

9
CABLE

CONNECTION

DIAGRAMS

10
AMBER

HEATER

INDICATOR

Q

CL

oco

I-<gQZzoe

ID$o

Q.Z

UJ

LD

DCo

ID

DC3 *

h-<

UJ oc CO UJ <J < a. 3 *

co oc > O

UJ

Ul

oc 2

UJ•”

H 1- _ x _l 3 2 < S O < o

oc o OC

K 3 Q

51 3 $

•“ < O UJ < 2 < (0 < OC

COOCO

0£ <

goS< 2?

LD

</) <

ID >

DC _J < uu < > O UJ Q CC z <

COzoQzoo2

oc<

_J<

UJZ<a

—iO

oc

i-zoo<m

oc

UJt-<$ < ±

oo

UJccoI—

Ll.

11
APPENDIX 1

la.

)

Constant Current Source

The constant current source (built at N.B.S.) is a fixed 10

micro amp source designed especially for the thermistor used in

the bath. Although the source is very well thermally stabilized,

it is advisable to leave it on at all times if possible. The

circuit is short circuit limited, so it is permissible to make

connections to it without turning off the power. A minimum of

one hour should be allowed before use, although 24 hours is

preferable

.

lb .

)

Thermistor

The four wire thermistor is a high precision laboratory

grade unit with a nominal room temperature (25 deg. C)

resistance of 4000 ohms. The stability of this unit is 0.005

degrees C per year, the temperature accuracy is better than

0.0015 degrees C over the range of 0 deg. C to 60 deg. C. Using

the current source described above we simulate the conditions

used to calibrate the thermistor.

lc. )DVM

The Hewlett-Packard 3457A DVM used in the system is accurate

to 0.0025% +/- 39 counts over 90 days on the 300 mV scale used by

the program. The short term accuracy is much better. When all

the calculations are made, the unit falls well within the

specifications necessary for this application.

Id. )DAC

The DAC is a 16 bit unit on a carrier card within the

computer chassis. It has been modified to operate over the range

of +0 to 1.0 V instead of +/- 10 . 0V by placing a resistor in

parallel with the feedback resistor at the output operational

amplifier. The change of the ourput voltage swing was necessary

for the correct operation of the bath with the additional benefit

of a smaller delta V per step for the DAC.

12
THERMOMETRICS

REPORT OF CALIBRATION

FOR

S-10 FOUR-WIRE THERMISTOR STANDARD

SERIAL NO 374

The above designated thermistor standard was calibrated i n Aug. -1985

, using

the test currents shown below.

The following calibration values were obtained and are traceable to the

National Bureau of Standards.

Temperature^ °C .01 25 30 32 37 fin 2 Resi stance

11224.36 3995.87 3307.43 3071.15 2560.92 1181.24

Test Current ya

5 ID ID ID LO ID

1. All temperature observations were made by comparison with a standard

platinum resistance thermometer L & N Model 8163, Serial No.422£D£

Calibration of the platinum standard at the triple point of water was performed prior to and after calibration of the S-10 Standard. The drift

in the platinum standard was found to be less than . 0 0.0.2 °C.

The uncertainty in the temperature measurement was less than 0.0015°C.

2. All resistance observations were made using a bridge whose readings were corrected against a ratio bridge, using comparison techniques. The ratio

bridge used has an accuracy of 0.0002%. Ratio measurements were made

against temperature controlled standard resistors having an accuracy of

0.001%. The total corrected resistance uncertainty was less than 0.0025%.

Approved by r~> yn/rr

808 U.S. HIGHWAY 1 EDISON. NEW JERSEY 08817 201-287-2870
S-10-4 WIRE STANDARD

WIRING DIAGRAM:

USE OF S-10-4 WIRE STANDARD :

The standard for which the attached calibration values and table apply was calibrated for use as a four- terminal device. As such, the lead resistance

does not enter into the measurement.

Should it become necessary or desirable to use this S-10 as a two-terminal

device, the following procedure should be used: •

a) Resistance between a single pair of terminals, 1-2:

.177 o hms per lead or a total of ,554 o hms to each

calibration or table value.

b) Resistance between terminals 1-1 connected in parallel and

terminals 2-2 connected in parallel:

Add ,177 o hms to each calibration or table value.

808 U S. HIGHWAY 1 EDISON, NEW JERSEY 08817 201-287-2870
Appendix 2: The Control Computer

15
DESKTOP, DUAL DISK DRIVE

IBM PC COMPATIBLE

SPECIFICATIONS:

MICROPROCESSOR 8088 CPU (16 bit) 4.77 MHz

Socket for 8087 co-processor

MEMORY 16K bytes ROM

128K bytes RAM

STORAGE Two 5 1/4 inch full-size Disk Drives x 360K bytes each (Operate double sided,

double density)

KEYBOARD IBM PC compatible layout

Soft Touch operation

Lock indicator lights

VIDEO CONTROLLER Color graphics or high resolution

monochrome

PERIPHERAL INTERFACES 2 Serial Ports (RS 232)

Parallel Port (IBM compatible)

DMA Controller (4 channel)

Interrupt Controller (8 level priority)

EXPANSION INTERFACES 8 Slots (full size); 7 available; IBM PC

compatible

POWER 100 Watt, 110/120 AC, 50/60 Hz

System Reset Button

UI listed FCC CLass B/CSA appr.

CONSTRUCTION Steel and Pla-stic cabinet

SIZE

WEIGHT

CPU 22.5 (w) x 15 (d) x 5 (h) inches

25 pounds

SERVICE Nationwide through Bell G. Howell Service Co

16
NBS-I14A i rev. 2-80

U.3.S DEPT. OF COMM.

BIBLIOGRAPHIC DATA

1. PUBLICATION OR

REPORT NO.

2. Performing Organ. Report No. 3. Publication Date

SHEET (See instructions) NBSIR 86-3477 OCTOBER 1986

4. TITLE AND SUBTITLE

Water Bath Black Body Operating Instructions

5. AUTHOR(S) , ^ Joel B. Fowler and Barbara J. Belzer

6. PERFORMING ORGANIZATION (If joint or other than NSS. see instructions)

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

7. Contract/Grant No.

8. Type of Report & Period Covered

9. SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City. State. ZIP)

SAME

10. SUPPLEMENTARY NOTES

| | Document describes a computer program; SF-I8S, FIPS Software Summary, is attached.

11. ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a si gnificant

bi bliography or literature Survey, mention it here)

This is an operating instruction manual for the water bath black body built

in the Radiometric Physics Division, National Bureau of Standards.

12. KEY WORDS ( Six to twelve entries ; alphabetical order; capitalize only proper names; and separate key words by semicolon s) Constant current source; computer; DAC; GPIB board; termperature control;

thermistor; water bath blackbody

13. AVAILABILITY 14. NO. OF

PRINTED PAGES

| x | Unlimited

| For Official Distribution. Do Not Release to NTIS 20

[ 1 Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. 15. Price

(jl! Order From National Technical Information Service (NTIS), Springfield, VA. 22161 $9.95

USCOMM-DC 8043-P90
Pm

I .

.

f