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S&C Instruction Sheet 712-501
Inspecting the Operation of
Circuit-Switcher Blades and
Blade Contacts
As indicated in S&C Data Bulletin 712-90, the
operation of the Circuit-Switcher blades and
the condition of the blade contacts should
be inspected every 2500 operations, or every
5 years, whichever occurs first .
The following procedure can be used to
inspect the operation of the Circuit-Switcher
blades and blade contacts:
Step 19
Remove the pullout motor and heater circuit
fuseholders to disconnect control power to
the switch .
Step 20
With the switch de-energized and grounded and
in the coupled position, firmly hand-crank the
disconnect to its fully open position .
Step 21
Check that the blades open to between 90° and
96° . See Figure 28 .
If the blade does not open 90° to 96°, check
that the cross base and pole-unit base are level,
and that no shifting of the mounting struc-
ture has occurred . Shim the pole-unit base or
readjust the height of the support structure
as required, to level the structure . Check that
the fasteners on the hinge end of the blade are
tight and in good condition .
NOTICE
If the blades do not make the correct angle,
or the contacts are not properly aligned after
leveling the base, halt the inspection and
contact your local S&C Sales Office .
Figure 28. Check the angle of the disconnect blades.
Level base
Pole-unit base
Disconnect
blade
90° to 96°
Inspection Recommendations
Summary of Contents for Mark VI
Page 28: ...Printed in U S A ...
