Dc Remote High Range Calibration - Cal Power TrueWave TW5250 Service Manual

SERVICE MANUAL
Wait for the DMM to settle. Take a DMM reading and record the value as RDGN1.
Query the output voltage of the TW and record the return string as MEAS1:
MEAS{1,2,3}:VOLT?
Set the TW to -220 volts DC by sending the following GPIB string:
SOUR{1,2,3}:VOLT:OFFSET –220
Wait for the DMM to settle. Take a DMM reading and record the value as RDGN2.
Query the output voltage of the TW and record the return string as MEAS2:
MEAS{1,2,3}:VOLT?
Calculate the gains and offset for the phase being calibrated:
GAIN1 = (MEAS1 – MEAS2) / (RDGN1 – RDGN2)
GAIN2 = (440.0) / (MEAS1 – MEAS2)
OFFSET = GAIN2 * MEAS1 – 220.0
Update the TW calibration registers by sending the following GPIB strings:
CAL{1,2,3}:MEAS:REM:LOR:VOLT:GAIN GAIN2
CAL{1,2,3}:OUTP:REM:LOR:VOLT:GAIN GAIN1
CAL{1,2,3}:OUTP:REM:LOR:VOLT:OFFSET OFFSET
Reset the TW's output to a safe condition:
SOUR{1,2,3}:VOLT:OFFSET 0.0
OUTPUT OFF

3.10 DC REMOTE HIGH RANGE CALIBRATION

Both the measurement and output subsystems are calibrated at the same time.
Connect the DMM to the output phase of the TW to be calibrated. Set the DMM for
auto–ranging volts DC. Send the following GPIB commands to the TW:
OUTPUT OFF
OUTP:COUP DC
Wait for the TW to complete its coupling change to DC; continue with this command:
SOUR:VOLT:RANGE HIGH
SOUR:SENSE REMOTE
SOUR{1,2,3}:CURR 5.00
OUTPUT ON
SOUR{1,2,3}:VOLT:OFFSET 0.0
CALIBRATION
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