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APPENDIX A – ELECTRICAL CALIBRATION
A3 Electrical Calibration Page
In this section the actual values denoted by 'x x x x x' are unimportant and are used to determine display reading stability when
carrying out the electrical calibration procedure.
        YES
xxxxx
mV Span 1  180mV
-----
ELECTRICAL CAL.
xxxxx
Calibrate     NO
xxxxx
mV Zero 1  -20mV
Operating Page
xxxxx
mV Span 2   40mV
xxxxx
mV Zero 2   10mV
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Adjust RTX Zero
25.0
Adjust CJ Value
-----
Adjust RTX Span
No Yes
Electrical Calibration Page
(To access this page refer to Fig. 7.1).
Calibrate
Select  YES to access the electrical calibration sequence. Select NO to
advance to the 
Adjust RTX Zero parameter.
mV Zero 1
Set the Cell simulator millivolt source to –20mV and allow the display to
stabilize.
mV Span 1
Set the Cell simulator millivolt source to 180mV and allow the display to
stabilize.
mV Zero 2
Set the Temperature simulator millivolt source to 10mV and allow the display to
stabilize.
mV Span 2
Set the Temperature simulator millivolt source to 40mV and allow the display to
stabilize.
Adjust Cold Junction Value
Measure the ambient temperature and set the display to the measured value,
in °C.
Adjust RTX Zero
Adjust the display until the milliammeter reads the minimum retransmission
level, i.e. 4mA.
Adjust RTX Span
Adjust the display until the milliammeter reads the maximum retransmission
level, i.e. 20mA.
Press   to return to the top of the Electrical Calibration Page.
Press 
 to return to the Operating Page.