Ohms/nS Calibration
Modifying the Displayed Value
You must modify the calibration constants to compensate for the measured lead
resistance. See Figure 4-13. Change the selected digit of the displayed nominal value by
pressing u [Modify value], u [[], or v []]. Select the next digit by
pressing t [Next Digit] and repeating the adjustment. Press x [Done] to end the
adjustment procedure.
For example, calibration at 190.00 ohms could proceed as follows:
•
Source = 190.0732 ohms (at output terminals)
•
Leads = 0.123 ohms
•
Altered value = source value (190.0732 ) + lead resistance (0.123) = 190.2962 ohms
The reading will appear as nominal with an arrow pointing to the digit to be adjusted.
With the GMM reading 190.00, the altered value should be rounded to 190.30. Use the
following key press sequence:
u [Modify value]
t [Next digit]
u [[] (unit digit = 3)
t [Next digit]
t [Next digit]
t [Next digit]
u [[] (unit digit = 1)
x [Done]
The nominal value for calibration has been modified.
Figure 4-13. Modifying the Displayed Value
Perfomance Testing and Calibration
Ohms/nS Calibration
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os11s.eps
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