Using The Decoupling Selector Handle - S&C Mark VI Instructions For Installation Manual

WIRING AND ADJUSTING THE SWITCH OPERATOR
Using the Decoupling Selector
Handle
Step 51
The selector handle is used to couple and
decouple the motor from the operating shaft.
Decoupling the motor allows the user to install
and confi gure control schemes and inspect the
operation of the motor without opening and
closing the disconnect.
To decouple:
The integral external selector handle, for
operation of the built-in internal decoupling
mechanism, is located on the right-hand side of
the switch operator enclosure. See Figure 47.
a. Swing the selector handle upright and slowly
rotate it clockwise 50° to the decoupled posi-
tion. See Figure 47.
b. Lower the selector handle to engage the
locking tab. The switch operator may be
operated either manually or electrically with-
out operating the disconnect. Moreover, in
the decoupled position, the switch operator
output shaft is prevented from moving by a
mechanical locking device located within
the switch operator enclosure. During the
intermediate segment of the selector handle
travel which includes the position at which
actual disengagement (or engagement) of the
internal decoupling mechanism occurs, the
motor-circuit source leads are momentarily
disconnected and both the opening and
closing motor contactors are mechanically
blocked in the open position. Look through
the observation window and verify that the
internal decoupling mechanism is in the
decoupled position. See Figure 48.
712-502
Figure 47. Selector handle operation.
Internal decoupling mechanism
(in decoupled position)
Figure 48. Verify switch is decoupled.
32
Selector handle
(being turned to
decoupled position)
Locking tabs
50°
Coupled
Decoupled
Selector handle
(in decoupled position)