Channel Isolation (*) - Fluke 435-II Service Manual

17. Increase the frequency to 3 kHz.
Fluke 435-II/437-II: check for a readout of 204.2 V or more.
18. Set the Calibrator to STBY.
Note: bandwidth will be slightly higher than in V/A/Hz mode because a low pass filter in
the analog input channel is off during Transients mode.

4.9 Channel Isolation (*)

This optional test verifies cross talk from voltage channels to current channels. Voltage
channels normally get high voltages while the current channels have a sensitivity of a
couple of volts. This way of testing verifies the most critical situation.
Proceed as follows:
1. Connect the Analyzer's A/L1, B/L2, C/L3, and N voltage inputs with the HI output
of the Calibrator.
Connect the Analyzer's GND input with the LO output of the Calibrator.
2. Set all current channels (Phase and Neutral) to 1 mV/A, 1000 A, x1 AC + DC, 1:1
(SETUP key, F4 – MANUAL SETUP, use arrow and ENTER keys).
Put the Analyzer in 3-phase WYE, 50 Hz, 400V, and V/A/Hz mode.
3. Short-circuit the four current inputs with a termination piece of 50 Ω or lower. Refer
to Figure 4-5.
4. Set the Calibrator to 800 V, 50 Hz, and OPR.
5. Check that the readout on all current channels does not exceed 19 A (this includes the
5 A basic error of the current channels).
6. Set the Calibrator to STBY.
7. Disconnect all test leads.
8. If removed, install the SD memory card again.
Performance Verification

4.9 Channel Isolation (*)

4
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