Precision Process Calibrator
Calibration Adjustment
31
Step 13: TC Read, TC mV Measure Adjustment
The adjustment of the TC source output range is similar to the first part of the voltage
source calibration. The Product outputs two adjustment points. After the output becomes
stable, the values can be entered at the PC. Use the test leads and a DMM for this
procedure.
Use a copper TC mini-plug cable with low thermal EMF jacks on the other end to
connect the Product to the DMM. Make sure the polarity is correct. Set the DMM to read
dc volts.
Enter
13
on the PC. The calibration of the TC read input range is based on the TC source.
Make sure that TC source is calibrated first.
The Product sources 5 calibration points:
•
-10 mV
•
15 mV
•
40 mV
•
65 mV
•
75 mV
For each test point, push 8 and 2 on the PC to adjust the output if necessary. Use the
8508A indication to monitor this voltage. After the output is within 1
μ
V of the necessary
value, push ENTER on the PC to go to the next calibration point.
Step 14: TC Cold Junction Temperature (TC CJC) Adjustment
The Calibration of the thermocouple cold junction temperature (TC CJC) is a critical part
of the adjustment process. It is important that the thermocouple junction be completely
stable. Use the precision thermometer, E thermocouple probe, lag bath, and thermistor
probe for this procedure. See Figure 4 for connections.
The precision thermometer probe must already be in the lag bath along with the E
thermocouple probe. Plug the mini-plug on the E thermocouple probe into the TC jack on
the Product.
Enter
14
at the PC
.
It is important that the thermocouple junction be completely stable.
After the TC junction is stable, enter the temperature from the temperature reference.
Push ENTER on the PC to return to the calibration menu.
Step 15: mA Read Adjustment
Connect 5522A mA source jacks to Product isolated jacks and add the 742A-1 resistance
standard in series. Use the sense jacks of the resistor to monitor the voltage drop on the
resistor with the 8508A DMM. See Table 3 for the test equipment used for this
procedure.
Connect 5522A mA source jacks to the Product isolated jacks and add the 742A-1
resistance standard in series. Use the sense jacks of the resistor standard to monitor the
voltage drop on the resistor with the 8508A DMM. See Table 3 for the test equipment
used for this procedure. See Figure 16 for connections.
Summary of Contents for 7526A
Page 6: ...7526A Calibration Manual iv ...
