e D A Q Am p User Manual

Quad Tc/mV Amp

Quad Amp
Channel 1
Tc/mV

Channel 2

Channel 3

Channel 4

150
Cu

+

Cu

+

Cu

+

Cu

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e-corder®

On-lineOn-lineOn-lineOn-linewww.eDAQ.com

This document was, as far as possible, accurate at
the time of printing. Changes may have been madeto the software and hardware it describes sincethen: eDAQ Pty Ltd reserves the right to alterspecifications as required. Late-breaking information
may be supplied separately. Latest information andsoftware updates can be obtained from our web
site.
Trademarks of eDAQ
e-corder and PowerChrom are registered trademarksof eDAQ Pty Ltd. Specific model names of data
recording units, such as e-corder 201, andPowerChrom 280, are trademarks of eDAQ Pty Ltd.
Chart and Scope are trademarks of ADInstruments
Pty Ltd and are used under license by eDAQ.
EChem is a trademark of eDAQ Pty Ltd.

Product: Quad Tc/mV Amp (EA150)
Document Number: U-EA150-0806
Copyright © August 2006
eDAQ Pty Ltd
6 Doig Avenue
Denistone East, NSW 2112
AUSTRALIA
http://www.eDAQ.com
email: info@eDAQ.com
All rights reserved. No part of this document may be
reproduced by any means without the prior written
permission of eDAQ Pty Ltd.

Other Trademarks
Mac OS, and Macintosh, are registered trademarksof Apple Computer, Inc. Windows 98, Windows
Me, Windows 2000, and Windows XP aretrademarks of Microsoft Corporation.
PostScript, and Acrobat are registered trademarks ofAdobe Systems, Incorporated.
All other trademarks are the properties of theirrespective owners.

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On-lineContents

1 Overview 1

B Troubleshooting 17

How to Use this Manual 2
Checking the Quad Tc/mV Amp 2eDAQ Amps 2

C Specifications 19

2 The Quad Tc/mV Amp 5
The Front Panel 6
The Thermocouple Inputs 6
The On-line Indicators 6
The Back Panel 7
The Signal Outputs 7
I2C Connector 7
Connecting to the e-corder 7
The Quad Tc/mV Amp Self Test 9
Using Chart software 9
Setting up the Quad Tc/mV Amp 9
Previewing the Signal 10
Calibration 12
Automatic Calibration 12
13
Manual Calibration 13

Index 21
License & Warranty 23

A Technical Aspects 15
Quad Tc/mV Amp Operation 15
Technical Description 15

Quad Tc/mV Amp

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iv

Quad Tc/mV Amp

C H A P T E R

1 Overview

O N E

The eDAQ Quad Tc/mV Amp is designed to work with an e-cordersystem, recording signals from up to four thermocouples (or other low
voltage sources) simultaneously.

Quad pH/mV Amp

1

How to Use this ManualThis manual describes how to set up and begin using your Quad
Tc/mV Amp. The use of the pH/mV Amp with the Chart software
Thermocouple Calibration extension is discussed. The appendicesprovide technical and troubleshooting information.

Checking the Quad Tc/mV Amp
Before you begin working with the Quad Tc/mV Amp, please checkthat:• all items described in the packing list are included; and that• there are no signs of damage that may have occurred duringtransit.
Contact your eDAQ distributor if you encounter a problem.
You should also become familiar with the basic features of youre-corder system, which are discussed in the e-corder Manual which will
be installed on you hard disk.

eDAQ Amps
The Quad Tc/mV Amp is part of a family of preamplifiers known aseDAQ Amps.
The Quad Tc/mV Amp is designed for recording signals from up to four
pH and other potentiometric electrodes. As with other eDAQ Amps, it isdesigned to be operated under full software control and is
automatically recognized by Chart or Scope software which controls its
gain range, signal filtering, and other settings.

2

Quad pH/mV Amp

The range of eDAQ Amps includes the:• Quad pH/mV Amp, suitable for connection of pH, ion selective,
and potentiometric (ORP) electrodes• Potentiostat, a three–electrode potentiostat that can be used forvoltammetric and amperometric experiments. Gain ranges of 20 nA
to 100 mA in 1:2:5 steps.
• Picostat, a high sensitivity three–electrode potentiostat suitable foruse with carbon fibre and other microelectrodes. Current gain
ranges of 10 pA to 100 nA in 1:2:5 steps.
• QuadStat, a four channel, three electrode potentiostat suitable foruse with amperometric biosensors. Current gain ranges of 2 nA
to1 mA/channel in 1:2:5 steps.
• Bridge Amp, suitable for sensors requiring a low drift, high gain
differential amplifier. Also provides DC excitation• GP Amp, suitable for high output sensors requiring a highimpedance single ended or differential amplifier. Also provides DC
excitation.
See our web site at www.eDAQ.com for more information.

Chapter 1 — Overview

3

4

Quad pH/mV Amp

C H A P T E R

T W O

2 The Quad Tc/mV Amp
This chapter describes how to connect and use your eDAQ Quad
Tc/mV Amp.

IMPORTANT: Always make sure that the e-corder is turned off before
you connect or disconnect the Quad Tc/mV Amp. Failure to do thismay result in damage to the e-corder and/or the Quad Tc/mV Amp.

Quad pH/mV Amp

5

The Front Panel
The front panel of the Quad Tc/mV Amp is shown in Figure 2–1.

The Thermocouple Inputs
The miniature thermocouple input connectors marked ‘Cu’ and ‘+’ of the
Quad Tc/mV Amp provide connection for most types of thermocouple.

The On-line Indicators
When lit, these indicate that the Chart software has located andinitialized the Quad Tc/mV Amp. If the light does not go on when thesoftware is run, check that the Quad Tc/mV Amp is properly
connected.

Figure 2–1
The Quad Tc/mV Amp
front panel

Qua
uad
d Amp
Channel 1
Tc/mV
/mV

Channel 2

Channel 3

Cu

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+

Cu

On-line+On-line+Cu

On-lineThermocouple connector

Temperature signals, BNC connectors

Figure 2–2
The Quad Tc/mV Amp
back panel

Channel 4

150

Channel 4

Channel 3

Channel 2

Cu+

On-lineOn-line indicator

Chassis ground, 4 mm post

Channel 1

No user serviceable parts inside.
Refer servicing to qualified service personnel.
2

Input

I C
Bus

OutputMade in Australia by eDAQ Pty Ltd.

DB–9 pin, I2C connectors

6

Quad pH/mV Amp

The Back Panel
The back panel of the Quad Tc/mV Amp is shown in Figure 2–2.

The Signal Outputs
The Quad Tc/mV Amp provides four signals, one for each sensing
thermocouple. These signals are accessed on the Quad Tc/mV Amp
back panel via four BNC connectors labelled Channel 1 — Channel 4.

I2C Connector
The back panel, Figure 2–2, has two DB-9 pin ‘I2C bus’ connectors
labelled Input and Output. The Input connector enables connection to
the e-corder (or to the output of other eDAQ Amps). This connection
provides power to the Quad Tc/mV Amp and carries the various
control signals (for gain range and filter selection) to and from thee-corder. The pin assignments are shown in Figure 2–3.

Connecting to the e-corder

1

5
6

9
Input

Chapter 2 — The Quad Tc/mV Amp

INT

DSD

SDA

DSC

I2C control signals

SCL

Regulated +17 V DC

Regulated +8 V DC

Regulated –17 V DC

Digital Ground

INT
DSD
SDA
DSC
SCL

Figure 2–3
I2C connector pin
assignments

Power lines

Regulated –17 V DC
Digital GroundI2C control signals

Regulated +17 V DC
Regulated +8 V DC

Your Quad Tc/mV Amp will have been supplied with an I2C cable (DB9 pin connectors at either end), and four cables with BNC connectors
at either end.

5

1

9

6
Output7

First make sure that the e-corder is turned off. Then connect the I2C
cable to the I2C connector on the back panel of the e-corder, and theother end to the I2C Input connector on the back panel of the pH/mV
Amp. Use BNC cables to connect the signal outputs on the back panelof the Quad Tc/mV Amp to the front panel of the e-corder as shown in
Figure 2–4 and Figure 2–5.
Check that all connections are firm. Loose connections may cause
failure to recognize the eDAQ Amp by the software, erratic behavior,or loss of signal.
Multiple eDAQ Amps can be connected to an e-corder. The numberthat can be connected depends on the number of input channels on thee-corder. The initial eDAQ Amp should be connected as shown in
Figure 2–5. The remainder are linked via I2C cables, connecting the
I2C output of one eDAQ Amp to the I2C input of the next. The signal
outputs of each eDAQ Amp are connected to an input channel of thee-corder.

Figure 2–4
Four thermocouples
shown connected to a
Quad Tc/mV Amp ande-corder 401

Channel 1

168

Cu

d
late
iso

Channel 2+

On-lineChannel 3

+

Cu

Cu

On-lineOn-lineInput 1401+

Input 2Channel 4
Cu+

On-lineInput 3

Power
OutputStatus

Input 4

Trigger

Channel 4

Figure 2–5
Back view of Quad
Tc/mV Amp connected
to e-corder

Channel 3

Channel 2

Channel 1

No user serviceable parts inside.
Refer servicing to qualified service personnel.

Input

OutputMade in Australia by eDAQ Pty Ltd.

No user serviceable parts inside.
Refer servicing to qualified service personnel.

2

I C Bus8

Made in Australia by eDAQ Pty Ltd.

Rated Voltage: 90 - 250 V AC
50/60 Hz 25 VA

Quad pH/mV Amp

The Quad Tc/mV Amp Self Test
After you have installed the software, connected the e-corder to acomputer as described in your e-corder Manual, and connected the
Quad Tc/mV Amp as described above, a quick check can be
performed:• Turn on the e-corder and check that it performs its normal
diagnostic tests, as described in the e-corder Manual• Once the e-corder is ready, open Chart software.
• During initialization, you should see these indicators flash briefly
and then remain lit — the Quad Tc/mV Amp is ready for use.
If the indicators do not light, check your cable connections and repeat
the procedure. If this does not solve the problem, contact your eDAQ
distributor.

Using Chart software
Setting up the Quad Tc/mV Amp
When the Quad pH/mV Amp is connected to an e-corder input andsuccessfully installed, the Quad Thermocouple… menu commandappears in the Chart software Channel Function pop-up menu, Figure
2–6.

Figure 2–6
Accessing the Quad
Tc/mV Amp controls

Choosing the Quad Thermocouple… menu command will access the
Quad Thermocouple dialog box (which replaces the normal e-corder

Chapter 2 — The Quad Tc/mV Amp

9Input Amplifier dialog box for that e-corder channel — your Chart
Software Manual have details on the Input Amplifier dialog box).

Previewing the Signal
The Quad Thermocouple dialog box, Figure 2–6, allows you topreview a signal so that you can select the amplification and filter
settings.
Select thermocouple type
Select input
channelFigure 2–7
The Quad Tc/mV Amp
dialog box, forpreviewing a signal(Chart software on a
Windows Computer)e-corder input
channel number

Pause/Resume buttons

Gain range(sensitivity)

Average signal
amplitude

Select filter
Preview signal

Drag labels and tickmarks to adjust axis

The incoming signal is displayed in real time, but is not recorded tohard disk (once the signal moves across the display area it is lost). Clickthe OK button to apply the selected settings.

Signal Display
The input signal is displayed so that you can see the effect of changing
the settings. The average signal value is displayed at the top left of thedisplay area.
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Quad pH/mV Amp

You can stop the signal scrolling by clicking the Pause button at the top
right of the display area
. Click the Scroll button
to resumescrolling.
You can shift and stretch the vertical Amplitude axis to make the bestuse of the available display area (see the Input Amplifier dialog in theChart Software Manual for further details). Changes made here update
settings in the main window of the program.

Thermocouple Type
Select the appropriate thermocouple type from this menu. If ‘mV’ ischosen then the raw millivolt signal will be shown. If any other selection
is made then the ice point corrected thermocouple signal will be shownin units of mV corresponding to the emf values listed in the NIST ITS–90
thermocouple tables, see http://srdata.nist.gov/its90/main/.

Setting the Range
Use the Range pop-up menu to select the input range (sensitivity) of thechannel. Available ranges are shown in Table 2–1. Signals in excess of
the range value will be truncated.

Filtering
The low pass filter will remove high frequency noise. For mostthermocouple probes filter values of 1 – 10 Hz will be appropriate.
The Mains Filter,, removes 50 or 60 Hz interference due tomains hum. See the Chart Software Manual for more information. For
most applications it is recommended to have the Mains Filter on.

Table 2–1
Ranges available fordifferent input settings.

Available ranges (°C) for various thermocouple types
mV
B

E

J

K

N

R

S

T

±20

1820

290

360

485

585

1680

1760

250

±10

1500

150

180

250

320

960

1040

115

±5

1020

80

95

120

170

550

580

60

±2

630

35

40

50

75

260

265

30

Chapter 2 — The Quad Tc/mV Amp

11

Units Calibration
Clicking the
button access the Units Conversion dialog box.
For more information about Units Conversion, see the Chart Software
Manual. This type of calibration should only be used for small
temperature ranges that can be calibrated with only two accurately
known temperature sources.
See the next section for calibration of probes, without the need ofaccurately known temperature sources.
When calibration is required over a wide range of temperature andseveral accurately known temperature sources are to be employed thenuse the Multiple Point Calibration extension.

Calibration
Automatic Calibration
The Thermocouple extension is a Chart software plug-in that adds the‘Thermocouple...’ command to the Chart channel pop-up menus. The
latest version of the extension is available at
http://www.edaq.com/chart_extns_list.html
This extension:• allows the user to select the type of thermocouple (B, E, J, N, K, R,
S or T) being used;• applies a polynomial correction to convert the voltage signal todegrees (°C, °F, or K) according to the thermocouple ITS-90 tables,
see http://srdata.nist.gov/its90/main/
The resulting temperature values will usually be accurate within thetolerance of the thermocouple being used — consult your thermocouple
probe documentation. In most cases thermocouples conform to either
the ANST/ANSI E230 Standard, or Special, Limits of Error, see
Table 2–2. In some cases, especially over limited temperature ranges,
manufacturers may guarantee better tolerances.

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Quad pH/mV Amp

Table 2–2

Limits of Error for
Thermocouples,
Reference Junction
0 °C (32 °F)

Tc
Type
T

J

E

K

N

R, S

B

Temperature Range

Limits of Error°C°F

Standard

Special–200 to –66–328 to –87

±1.5%

—

–66 to 0–87 to +32±1°C, ±2°F—

0 – 133

32 – 270±1°C, ±2°F

±0.5°C, ±1°F

133 – 350

270 – 662

±0.75%±0.4%

0 – 293

32 – 559

293 – 750

559 – 1382

±0.75

0.4%

–200 to –100

–328 to –148

±1%—–100 to 0–148 to +32±1.1°C, ±3°C—

0 – 340

32 – 644±1.7°C, ±3°F

±1°C, ±2°F

340 – 900

644 – 1652

±0.5%

±0.4%

–200 to –110

–328 to –166±2%—–110 to 0–166 to +32±2.2°C, ±4°F—

0 – 293

32 – 559

293 – 1250

559 – 2282

0 – 293

32 – 559

0 – 1250

559 – 2282

0 – 600

32 – 1112

600 – 1450

1112 – 2642

±0.25%±0.1%

870 – 1700

1598 – 3092

±0.5%

—

±2.2°C, ±4°F ±1.1°C, ±2°F

±2.2°C, ±4°F ±1.1°C, ±2°F
±0.75%±0.4%±2.2°C, ±4°F ±1.1°C, ±2°F
±0.75%±0.4%±1.5°C, ±3°C ±0.6°C, ±1°F

Manual Calibration
If known temperature sources are available then very accurate
calibration can be achieved using the raw mV signal setting. The signal
can be calibrated over small ranges with a linear function using theChart software Units Conversion feature (see the Chart Software
Manual). Over wider ranges the Multipoint Calibration extension
software plug-in can be used, see
http://www.edaq.com/chart_extns_list.html
Chapter 2 — The Quad Tc/mV Amp

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14

Quad pH/mV Amp

A

P

P

E

N

D

I

X

A

A Technical Aspects

This appendix describes the some of the important technical aspects of
the Quad Tc/mV Amp. You do not need to know the material here to
use the Tc/mV Amp. Please remember that user modification of theequipment voids your rights under warranty.

Quad Tc/mV Amp Operation
The Quad Tc/mV Amp, and other eDAQ Amps, have been designed to
be used with an e-corder system. The Tc/mV Amp provides:• high impedance, electrically isolated inputs suitable for directconnection to most thermocouples;• cold junction compensation;• software controlled filtering of the signal;• software selectable gain ranges.

Technical Description
As with other eDAQ Amps, all internal functions of the Quad Tc/mV
Amp are controlled from the e-corder by sending information on a
special communications connection called the I2C (eye-squared-sea)bus. This connection supplies power to the eDAQ Amp as well. eDAQ
Amps are connected to the analog input channels of the e-corder via
BNC-to-BNC cables, through which the amplified and filtered signal is

Quad pH/mV Amp

15

sent to the e-corder. The overall operation of the pH/mV Amp can bebetter understood by referring to Figure A–1.
The thermoucouple signal is first amplified (× 100) and then passed
though an isolation transformer. The signal is then ice point corrected,
low pass filtered and then sent to the e-corder for secondary
amplification and filtering.

Figure A–1
Block Diagram of the
Quad Tc/mV Amp
Front Panel

Back Panel
Gain adj

Tc connector

Isolation

× 100

×1

Tc connector

× 100

×1

Tc connector

× 100

×1

Tc connector

× 100

×1

Ice pointreference+

Low pass filter

Tc signal

Low pass filter

Tc signal

Low pass filter

Tc signal

Low pass filter

Tc signal

Online indicator

16

Calibration
microprocessor
Isothermal block

Temperature
sensor+++I2C output

Quad DACI2C interface

I2C input

Quad pH/mV Amp

A

P

P

E

N

D

I

X

B TroubleshootingB

If you experience any difficulty with the Quad pH/mV Amp use thissection to try to resolve the problem. In the majority of cases, theproblem can usually be fixed by ensuring that the connecting cables
are correctly connected and firmly attached and the re starting theChart or Scope software.
The On-Line indicator fails to light when Chart or Scope is opened• If the e-corder is off check switches and power connections.
• The BNC to BNC cables from the Tc/mV Amp to the analog input
channels of the e-corder may not be properly connected. Check thateach cable is firmly connected to the BNC connector on the backpanel of the pH/mV Amp and to a BNC input on the front panel ofthe e-corder.
All or some of on-line indicators fail to light when the Chart software is
opened, and the pH/mV Amp controls are not accessible• If all the lights are off, then the I2C cable from the Tc/mV Amp to
the e-corder may not be properly connected. Check to see that theI2C cables are firmly seated and screwed in.
• Try a new cable to check that the BNC and/or I2C cables areworking correctly.
• If you have tried the above suggestions and still cannot get the
Quad Tc/mV Amp to work properly, then try using it on anothere-corder if you have access to one. If the on-line indicators still fail tolight on the second e-corder, the Quad Tc/mV Amp unit may be
faulty and should be returned for repair.

Quad Tc/mV Amp

17

18

Quad Tc/mV Amp

A

P

P

E

N

D

I

C Specifications

X

C

Quad Tc/mV Amp

Quad Tc/mV Amp

Tc/mV Amplifier:

Four.
High impedance, electrometer type.
Galvanically isolated.

Input range:±20 mV

Secondary ranges:±10, 5, 2 mV, supplied by e-corder

Input resolution:

16 bits, 0.0015% of range

Input impedance:

1013 Ω typical

Amplifier noise:< 1µV rms (4 µV p–p) @ DC – 10 Hz

Maximum Input:±10 V

Input Connection type:miniature thermocouple

Bandwidth/Low pass filter:-3 dB @ 10 Hz
3 pole Bessel

Secondary filters:

5, 2, 1 Hz (digital filters of e-corder)

19

Control PortI2C input and output:

Male and female DB–9 pin connectors.
Provides control and power.

Power requirements:±17 V DC
+8 V DC~3 W

Physical Configuration
Dimensions (h × w × d):

60 × 150 × 200 mm
2.4 × 5.9 × 7.9 inches

Weight:

1.5 kg (3.3 lb)

Operating conditions:0 – 35˚C
0 – 90% humidity (non–condensing)eDAQ reserves the right to alter these specifications at any time.

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Quad Tc/mV Amp

Quad Amp
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Tc/mV
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On-line

Index

B

I

back panel 7

I2C connector 7
pin assignments 7

block diagram 16
Bridge Amp 3

Ccalibration 12
checking the Quad Tc/mV Amp 2

L
limits of error 13

P

connecting multiple eDAQ Amps 8

pH Ampdialog box 10

E

Picostat 3

eDAQ Amps
Bridge Amp 3
GP Amp 3
Picostat 3
Potentiostat 3
Quad pH/mV Amp 3
Quad Tc/mV Amp 2
QuadStat 3

Ffiltering 11
front panel 6

Potentiostat 3
previewing the signal 10
probe calibration 12
problems 17

Q
Quad pH/mV Amp 3
Quad Tc/mV Amp 2
setup 9–12
use with Chart software 9
QuadStat 3

G
GP Amp 3

Quad Tc/mV Amp

21

S
setting the sensitivity 11
signal calibration 12
signal outputs 7
signal preview 10
specifications 19

Ttechnical specifications 19–20
Temperature Amp
dialog box 10
thermocouple calibration 12
thermocouple connectors 6
thermocouple inputs 6
thermocouple limits of error 13
thermocouple type 11
troubleshooting 17

Uuser modification 15

Wwarranty conditions 15, 23

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Quad Tc/mV Amp

Quad Amp
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Tc/mV
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License & Warranty

On-lineTrademarks
e-corder and PowerChrom are registeredtrademarks of eDAQ Pty Ltd. All eDAQ software,
hardware, and documentation is protected bycopyright. eDAQ retains the exclusive ownership of
the trademarks and registered trademarks
represented by its company name, logo, andproduct names.

Responsibilities
You and any others using any eDAQ product agree
to use it in a sensible manner for purposes for which
it is suited, and agree to take responsibility for theiractions and the results of their actions.
If problems arise with an eDAQ product, eDAQ will
make all reasonable efforts to fix them. This service
may incur a charge, depending on the nature of the
problems, and is subject to the other conditions inthis Agreement.

Hardware Warranty
eDAQ Pty Ltd warrants the Quad Tc/mV Amp, to be
free of defects in material and workmanship for one
year from the date of purchase. eDAQ Pty Ltd will
repair or replace defective equipment as
appropriate.
To obtain a warranty repair/replacement you mustfirst notify us before return of the instrument and wewill issue you with a RAN (return authorization
number). You must ship the defective product at your

Quad Tc/mV Amp

expense. We will pay return shipping. The productshould be packed safely (preferably in its original
packaging) and have the RAN on the shippinglabel. Returns sent without a RAN may be refuseddelivery.
This warranty does not cover hardware that has:• been modified by the user in any way;
• been subjected to unusual physical, electrical,
or environmental stress. This includes damage
due to faulty power sockets, inadequate
earthing, or power spikes or surges;• been damaged because of incorrect wiring toancillary equipment, or because of substandard,connectors or cables; or• had the original identification marks removed
or altered.

Software License
You have the non-exclusive right to use the suppliedeDAQ software (Chart, Scope etc). Your employees
or students, for example, are entitled to use it,provided they adhere to this agreement. Eachseparate purchase of the eDAQ software licenses it
to be used on two computers at any given time (onone computer for data acquisition with a e-corder
hardware unit, and on a second computer for the
analysis of existing data files). Although multiple
copies of a program may exist on several
computers, more than two copies must not be usedsimultaneously. Departmental/company licences are23

available if you wish to run more than two copies
simultaneously.

Technical Support
Please register your unit to receive technical support.
Technical assistance is available via email. Please
describe the problem with as much detail as
possible. Include a small example data file, if
appropriate. Please also state:• the model and serial number of your e-corderunit and Quad Tc/mV Amp.
• the type of computer and operating systembeing used (for example Windows XP, or
Macintosh OS 10.2)• the software version you are using (forexample Chart v5.1.2)
We endeavor to answer all your questions, but insome cases, for example where the problem relates
to the other equipment that you are using, a nominal
fee may be charged.

Jurisdiction
eDAQ Pty Ltd is bound by the laws of New South
Wales in Australia, and any proceedings shall beheard by the Supreme Court of New South Wales inAustralia.

Disclaimer
eDAQ reserves the right to alter specifications ofhardware and software without notice.
No liability can be accepted for consequential
damages resulting from use of eDAQ products.

24

Quad Tc/mV Amp