Instruction Book
Page 41
IB131009EN
Figure 6-4 Breaker shown closed and interrupter
erosion satisfactory (3150A)
Figure 6-5 Breaker shown closed and interrupter
erosion unsatisfactory (3150A)
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.
6-6
INSULATION
In W-VAC, W-VACR and W-VACW breakers, insulation
maintenance primarily consists of keeping all insulating
surfaces clean. This can be done by wiping off all insu-
lating 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 Eaton
55812CA or commercial equivalent.
Secondary control wiring requires inspection for tight-
ness of all connections and damage to insulation.
6-7
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 12kv. and 15 kv. the test voltages are 21
kv and 27 kv. rms respectively. Conduct the test as fol-
lows:
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.
Secondary Circuit:
Isolate the motor by pulling apart the two insulated quick
disconnecting terminals in the two motor leads provided
for this purpose. Connect all points of the secondary dis-
connect pins with a shooting wire. Connect this wire to
the high potential lead of the test machine. Ground the
breaker frame. Starting with zero, increase the voltage to
1500 volts rms. Maintain the voltage for one minute.
Successful withstand indicates satisfactory insulation
strength of the secondary control circuit. Remove the
shooting wire and reconnect the motor leads.
Erosion gauge
Erosion mark
Pointer portion of the gauge
is below the erosion mark
Pole unit support
Pointer portion of the gauge is
aligned or above the erosion mark
WARNING
Summary of Contents for W-VAC Series
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