S&C Instruction Sheet 695-545 17
Low-Voltage Phasing Using Optional Voltage-
Indication Feature
STEP 1. Using water and mild soap, if necessary, clean
the surface of the operating mechanism front
panel around the Potential Indication feature.
Petroleum-based solvents should not be used on
or around Vista SD Underground Distribution
Switchgear.
STEP 2. Unscrew the aluminum cap covering the
Voltage-Indication feature.
STEP 3. Using a high-impedance true RMS-reading
voltmeter, set to read ac volts, determine the
phase-to-neutral voltage for each phase of the
two ways to be phased as follows:
(a) Set the voltmeter for volts ac.
(b) Connect one of the test probes of the voltmeter to
the neutral jack of the way to be phased.
(c) Place the other test probe on each of the test
jacks, in turn, of the two ways to be phased and
measure the phase-to-neutral voltage. See
Figure 24 (a), (b), and (c).
(d) If the voltage measured at each test jack is greater
than 0.5 Vac and they are equal, proceed to
Step 4 on page 18.
(e) If the voltage measured at any of the test jacks is
less than 0.5 Vac, the phases are not energized
and phasing cannot be performed. If the voltages
measured are not equal, the voltmeter may not be
operating properly. Phasing should be performed
using an alternate method.
Figure 24. Measure the phase-to-neutral voltage of each phase
of each way to be phased.
Operation
(b)
(c)
(a)
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