Cal Power TrueWave TW5250, Service Manual

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SERVICE MANUAL CALIBRATION
3-29
Reset the TW back to AC coupling mode, output off.
SOUR {1,2,3} :VOLT:OFFSET 0.0
OUTP OFF
OUTP:COUP AC
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:LOR:CURR:GAIN GAIN
CAL {1,2,3} :MEAS:REM:LOR:CURR:GAIN GAIN
3.20 LOCAL LOW RANGE WATTS CALIBRATION
Connect the 12 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, low range, local sense, 13 ampere current limit, output
relay closed and 54 volts with the following GPIB programming strings:
OUTP:COUP AC
SOUR:VOLT:RANGE LOW
SOUR:SENSE LOCAL
SOUR
{1,2,3} :CURR 13.00
OUTPUT ON
SOUR
{1,2,3} :VOLT 54
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 134 volts AC using the string below:
SOUR {1,2,3} :VOLT 134
Wait until the power analyzer has stabilized and record the watts reading as RDNG2 .