S&C Instruction Sheet 695-510 19
Operation
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. Petro-
leum-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 volt-
meter, 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 31 (a), (b),
a nd (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 20.
(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 mea-
sured are not equal, the voltmeter may not be op-
erating properly. Phasing should be performed
using an alternate method.
(a)
(b)
(c)
Figure 31. Measure the phase-to-neutral voltage of each phase
of each way to be phased.
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