Instruction manual

97
4.4. NONPERIODIC CALIBRATION
A nonperiodic calibration will only be required if a related assembly is repaired or if the
performance is out of specification.
4.4.1. OUTPUT FREQUENCY CALIBRATION
Connect the Frequency Counter to the phase A output. Program the output to 135.0 volts and 400.0
Hz. Engage the low-pass filter on the Frequency Counter to obtain the output frequency.
If the Frequency Counter does not indicate 400.000 ±0.004 Hz, adjust C43 for the correct
frequency. Refer to Figure 4-2.
4.4.2. GAIN ADJUSTMENT
CAUTION: The Gain Balance Adjustment should be made if an amplifier, curret limit
or an oscillator/controller assembly has been repaired.
Remove all loads from the output. Disconnect the remote sense input to TB2. Remove the
module behind the left front panel subpanel and reinstall the module with the extender board
(California Instruments 5000-709-1).
1. Coonnect the AC DVM to the phase A output.
2. Program the output to 75% of full scale voltage and 60 Hz. Press and hold the
ENT key to keeep the output from defaulting.
3. Adjust R90 on the left subpanel module (Refer to Figure 4-1) for an output of
86% of full scale voltage, ±0.1% of full scale.
4. Repeat steps 1 thruouh 3 for a three-phase power system. For step 3, adjust R91
for phase B and R92 for phase C.
5. Turn off the circuit breaker and reinstall the left front panel module without the
extender board.
6. Re-connect the remote sense lines.