Local High Range Watts Calibration - Cal Power TrueWave TW5250 Service Manual

SERVICE MANUAL
Calculate the gain from the collected data:
GAIN = (RDGN2 – RDNG1) / (MEAS2 – MEAS1)
Update the TW's gain setting using the GPIB strings below:
CAL{1,2,3}:MEAS:LOC:HIR:CURR:GAIN GAIN
CAL{1,2,3}:MEAS:REM:HIR:CURR:GAIN GAIN

3.26 LOCAL HIGH RANGE WATTS CALIBRATION

Connect the 48 ohm resistor to the output of the TW through the power analyzer. Set
up the power analyzer to measure watts.
Set up the TW to AC coupling, high range, local sense, 6.5 ampere current limit, output
relay closed and 108 volts with the following GPIB programming strings:
OUTP:COUP AC
SOUR:VOLT:RANGE HIGH
SOUR:SENSE LOCAL
SOUR{1,2,3}:CURR 6.5
OUTPUT ON
SOUR{1,2,3}:VOLT 108
Wait until the power analyzer has stabilized and record the watts reading as RDNG1.
Query the TW's watts using the GPIB string below, and record this value as MEAS1.
MEAS{1,2,3}:POW?
Program the TW to 268 volts AC using the string below:
SOUR{1,2,3}:VOLT 268
Wait until the power analyzer has stabilized and record the watts reading as RDNG2.
Query the TW's watts using the GPIB string below, and record this value as MEAS2.
MEAS{1,2,3}:POW?
Turn the TW's output off via the GPIB:
OUTP OFF
Calculate the gain and offset values for updating the TW:
GAIN = (RDGN2 – RDGN1)/(MEAS2 – MEAS1)
OFFSET = RDGN2 – GAIN * MEAS2
CALIBRATION
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