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

SERVICE MANUAL
Wait for the phase angle measurement to stabilize on the counter timer. Record the
phase angle as RDGN4.
Set the TW frequency to 320 Hz:
SOUR:FREQ 320.0
Wait for the phase angle measurement to stabilize on the counter timer. Record the
phase angle as RDGN5.
Set the TW frequency to 60 Hz and output off:
SOUR:FREQ 60.0
OUTP OFF
Calculate the phase angle compensation values:
VALUE1 = -1.0 * RDGN1
VALUE2 = -1.0 * RDGN2
VALUE3 = -1.0 * RDGN3
VALUE4 = -1.0 * RDGN4
VALUE5 = -1.0 * RDGN5
Update the phase A offset calibration data via the GPIB:
CAL:UNIQ:OPHA VALUE1 VALUE2 VALUE3 VALUE4 VALUE5

3.16 PHASE A TO PHASE B CALIBRATION

Note: this calibration step only applies to TW3500 and 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 B 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 B, low range, local sense, 40 Hz, 120V
and close the output by sending the following GPIB commands:
SOUR2:PHAS 0
SOUR:VOLT:RANGE LOW
SOUR:SENSE LOCAL
SOUR:FREQ 40.0
SOUR:VOLT 120.00
OUTPUT ON
Wait for the counter timer to settle and record the phase angle as RDNG1.
CALIBRATION
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