S&C Vista - Page 28

28 S&C Instruction Sheet 682-510
Operation
Figure 50� Measuring the phase-to-phase voltage — Phase
1 to Phase 1
Figure 51� Measuring the phase-to-phase voltage — Phase
2 to Phase 1
Figure 52� Measuring the phase-to-phase voltage — Phase
3 to Phase 1
STEP 4� Determine the phase-to-phase relationships of
the two ways to be phased as follows:
(a)
Remove the test probe of the voltmeter from
the switchgear tank.
(b) Place one of the test probes on Phasing Pin
1 of the rst way and place the other probe
on Phasing Pin 1 of the second way. Mea sure
the phase-to-phase voltage. See Figure 50.
When comparing the same phase of the two
ways, the voltage should be zero or close
to zero, indicating the cables are in phase.
(c) Keep the test probe on Phasing Pin 1 of the
second way and move the other test probe
to Phasing Pin 2 of the rst way. Measure
the phase-to-phase voltage. See Figure 51.
When comparing different phases of the two
ways, the voltage should be 1.7 to 2 times
the phase-to-ground voltage mea sured in
Step 3 on page 27.
(d) Keep the test probe on Phasing Pin 1 of the
second way and move the other test probe
to Phasing Pin 3 of the rst way. Measure
the phase-to-phase voltage. See Figure 52.
Again, when comparing different phases of
the two ways, the voltage should be 1.7 to 2
times the phase-to-ground voltage mea sured
in Step 3 on page 27.
(e) Repeat Steps 4(b) through 4(d) for Phasing
Pin 2 and Phasing Pin 3 of the second way.
(f)
If all of the phase-to-phase relationships
are correct, the cables are in phase and are
properly installed.