S&C Mark V Circuit-Switchers Installation Manual page 12

Installation
STEP 4� Each circuit-switcher pole-unit brain, with
its associated base-integrated power train,
is factory-adjusted to provide the sequence
control necessary to ensure positive latching
of the stored-energy source within the brain and
precisely timed opening of the interrupters. To
maintain this essential factory-adjusted brain-
and-power-train relationship during removal and
later reassembly of live parts, a brain adjustment-
holding device is provided. See Figure 5.
The adjustment-holding device consists of a stop
bushing, factory-set in the bracket attached to
the underside of the brain, plus a tab on the brain
operating shaft. When the pole-unit is opened,
the tab rotates to within 1/16 inch (1.6 mm) of
the stop bushing. A ½–13 X 2 ¾-inch positioning
bolt with flat washer and nut is furnished (in a
cloth bag attached to the operating-shaft tab) for
insertion through the stop bushing and the tab.
Install the positioning bolt as follows:
(a) Make sure the pole-unit is in the fully Open
position.
(b) At the brain mounting flange, loosen, but
do not remove, the cap screws which fasten
the brain to the rotating-insulator support
See Figure 5.
(c) Insert the positioning bolt through the tab
and stop bushing and secure it with the flat
washer and nut. Torque the nut tightly so the
two mating surfaces are drawn together.
See Figure 6.
12 S&C Instruction Sheet 711-510
½–13 X 2 ¾-inch
positioning bolt
Tab on brain shaft
Figure 5� Installing positioning bolt�
Figure 6� Positioning bolt after installation�
Factory-set
stop bushing
Loosen these bolts
before tightening
positioning bolt