Phase A To Phase C Calibration - Cal Power TrueWave TW5250 Service Manual

SERVICE MANUAL
Set the TW frequency to 60 Hz and open the output via the GPIB:
SOUR:FREQ 60.0
OUTP OFF
Calculate the phase offset calibration data:
VALUE1 = -1.0 * RDGN1
VALUE2 = -1.0 * RDGN2
VALUE3 = -1.0 * RDGN3
VALUE4 = -1.0 * RDGN4
VALUE5 = -1.0 * RDGN5
Update the calibration data via the GPIB:
CAL:UNIQ:OPHAB VALUE1 VALUE2 VALUE3 VALUE4 VALUE5
Calculate the phase angle readback calibration data:
VALUE1 = -1.0 * (RDGN1 + MEAS1)
VALUE2 = -1.0 * (RDGN2 + MEAS2)
VALUE3 = -1.0 * (RDGN3 + MEAS3)
VALUE4 = -1.0 * (RDGN4 + MEAS4)
VALUE5 = -1.0 * (RDGN5 + MEAS5)
Update the calibration data via the GPIB:
CAL:UNIQ:MOPHAB VALUE1 VALUE2 VALUE3 VALUE4 VALUE5

3.17 PHASE A TO PHASE C CALIBRATION

Note: this calibration step only applies to TW5250 systems.
Connect the counter timer channel 1 to the TW's A phase through a 10:1 resistor
divider. Connect the counter timer channel 2 to the TW's C phase through a 10:1
resistor divider. Set the counter time up to measure phase angle.
Set the TW up for 0 degrees phase A to phase C, low range, local sense, 40 Hz, 120V
and close the output by sending the following GPIB commands:
SOUR3:PHAS 0
SOUR:VOLT:RANGE LOW
SOUR:SENSE LOCAL
SOUR:FREQ 40.0
SOUR:VOLT 120.00
OUTPUT ON
CALIBRATION
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