AMETEK i-iX Series II - Manual (Page 147)

User Manual California Instruments
i Series II / iX Series II / iM Series II 147
6.6 Non-Routine Calibration
All internal adjustments are set at the factory at the time or original shipment. As such, non-
routine calibration is generally not required unless one or more amplifier assemblies have been
replaced in the field. In this case, perform the following sections in the order shown.
The non-routine calibration involves removing the top cover from the power source. Remove the
line power from the power source before removing the top cover. Most of the adjustments are
on the Current Limit Assembly. One adjustment is on I/O Board Assembly. Refer to Figure 6-3
for the location of the adjustments.
6.6.1 DC Offset Adjustment
1. Turn off the AC input power to the power source using the front circuit breaker. Not that
AC voltage is still present inside the unit so DO NOT touch the contacts of the circuit
breaker inside the unit.
2. Connect a 22
µ
F tantalum capacitor in series with a 100k
Ω
1% resistor across the
output.
3. Connect a DVM to read DC volts across the capacitor.
4. Short test point TP1 to test point TP6 on the Current Limit Board using a jumper wire.
5. Power up the unit in AC mode, 150 VAC range, 0.0 V programmed and close the output
relay. Adjust the DC offset to 0.0 mVDC +/-5.0 mVDC using R95 on the AC Logic Board.
6. Remove short on the Current Limit Board.
7. Open the output relay when done.
6.6.2 Current Monitor Offset Adjustment
1. Select Phase A.
2. Program the 300 VAC range, 0.0 volts, and turn the Output ON.
3. On the current limit board, monitor test point TP5 with respect to test point TP1
(common) using a DMM in VDC mode.
4. Adjust R23 on the input/output board for 0.0 mVDC
±
0.5 mVDC on TP5.
5. Cycle the AC input power using the front panel circuit breaker.
CAUTION: Use extreme care in adjusting R23. Do not touch any connections on the
Input/Output Board Assy. Dangerous voltages exist on most exposed connections.