Insulation; Insulation Integrity Check; Vacuum Interrupter Showing Contact Erosion Indicator With Breaker Open; Vacuum Interrupter Showing Contact Erosion Indicator With Breaker Closed - Eaton Cutler-Hammer VCP-WR 18 Series Instructions For The Use, Operation And Maintenance

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Figure 7-2 Vacuum Interrupter Showing Contact
Erosion Indicator with Breaker Open (Shown here for
Clarity Purposes Only).
horizontal portion shows with the breaker closed, the
wipe is not adequate, and the pole unit assembly must
be replaced.
!
FAILURE TO REPLACE A POLE UNIT ASSEMBLY
WHEN CONTACT EROSION MARK IS NOT VISIBLE
OR WIPE IS UNSATISFACTORY, WILL CAUSE THE
BREAKER TO FAIL TO INTERRUPT AND THEREBY
CAUSE PROPERTY DAMAGE OR PERSONAL
INJURY.

7-6 INSULATION

In VCP-WR breakers, insulation maintenance primarily
consists of keeping all insulating surfaces clean. This
can be done by wiping off all insulating surfaces with a
dry lint free cloth or dry paper towel. In case there is any
tightly adhering dirt that will not come off by wiping, it
can be removed with a mild solvent or distilled water. be
sure that the surfaces are dry before placing the breaker
in service. If a solvent is required to cut dirt, use
Stoddard's Solvent Cutler-Hammer 55812CA or com-
WARNING
Figure 7-3 Vacuum Interrupter Showing Contact
Erosion Indicator with Breaker Closed (Indicators are
Checked Only When Breaker is Closed).
mercial equivalent. Secondary control wiring requires
inspection for tightness of all connections and damage
to insulation.

7-7 INSULATION INTEGRITY CHECK

Primary Circuit:
The integrity of primary insulation may be checked by
the AC high potential test. The test voltage depends
upon the maximum rated voltage of the breaker. For the
breakers rated 5 kV, 12 kV and 15 kV the test voltages
are 15 kV, 21 kV and 27 kV rms respectively. Conduct
the test as follows:
Close the breaker. Connect the high potential lead of
the test machine to one of the poles of the breaker.
Connect the remaining poles and breaker frame to
ground. Start the machine with output potential at zero
and increase to the test voltage. Maintain the test volt-
age for one minute. Repeat for the remaining poles.
Successful withstand indicates satisfactory insulation
strength of the primary circuit.
If a DC high potential machine is used, make certain
that the peak voltage does not exceed the peak of the
corresponding AC RMS test voltage.
I.B. 8295A61H03
Effective 7/97