DISCONNECTING SWITCH
Operation & Maintenance Manual
06
3.2.2 - Manual Operation
A caution plate, as detailed below, is attached to the cover.
Check the interlock before proceeding to operate. The number
of rotation for the manual handle is about 17.
To Operate Disconnecting switch manually
1. Remove the Padlock of Latch and rotate the latch.
2. Open the shutter in the direction of the arrow .
3. Insert the manual handle so that it engages with the pin of
the shaft.
1) OPEN to CLOSE or EARTH to OPEN positions. Rotating the
manual charging handle clockwise will cause the
disconnecting switch to be operated.
2) CLOSED to OPEN or OPEN to EARTHED positions.
- Turn the manual handle counter-clockwise in the same
manner asabove.
- After completion of the operation, rotate the shutter
anticlockwise to release the lock. Then, remove the
charging handle. The shutter will return automatically to its
original position.
- The manual handle has a torque limiting feature which will
cause the handle to slip when a torque in excess of the
speci ed value is applied.
- When the handle slips, do not rotate the handle forcibly.
- Check for the correct direction of rotation. After
completion of manual operation i.e. when the switching
sound is heard, continue to rotate the operating handle for
approx. one and a half turns in the same direction of
rotation.
This is to enable the electrical interlocks to reset for the next
motor operation.
Rotate the shutter knob anticlockwise to remove the operating
Caution Before Manual Operation
1. Do not attempt to operate the Disconnecting switch if
the circuit breaker is in closed position.
2. When the circuit breaker is in CLOSED position,
interlocks prevents the shutter from being opened.
3. Do not operate DS manually in open door condition.
Figure 3.2.2 a - DS FACIA
handle. The shutter is spring loaded and will automatically close.
The interlock plunger resets as soon as the handle is removed.
3.2.3 - Emergency Operation
In case of emergency situations such as secondary power failure
the following procedure applies.
In the event of secondary power failure, the interlocks will
prevent the disconnecting switch from being operated manually.
To disable the interlocks of the disconnecting switch for manual
operation of open/close/earth, remove the cover by
rst
loosening those screws marked. The shutter interlock cam
&plunger which prevents cam rotation are accessible once the
cover is removed. Lift the plunger upwards with a screwdriver to
free the cam and shutter. The shutter can then be opened and it
is possible to insert the manual-charging handle for the required
operation.
3.3 - Interlock Features
The basic electrical and mechanical interlocks are provided
between the disconnecting switch (DS) and the circuit breaker
are as follows:
1) DS can be operated only when the circuit breaker is in open
condition.
2) While the DS is in operation, the circuit breaker cannot be
closed.
3) On line transfer can be achieved by electrical operation.
