5
Installation Checks and Initial Functional Tests
Figure 5:
Use of Extension Rails for Upper Compartment.
Removal from Lower Cell in Indoor (if not on raised pad)
and Shelter-Clad Outdoor Switchgear -
1. Open the circuit breaker.
2. If the circuit breaker is in the Connect position, insert
the racking crank on the racking screw on the front of
the breaker cell, and push in. This action operates the
racking interlock latch.
Figure 3
shows racking of a
circuit breaker in the upper cell - the process is similar for
a breaker in the lower cell. Rotate the racking crank coun-
terclockwise until the circuit breaker is in the Test
position. (If the circuit breaker is in the Disconnect
position, turn the racking crank clockwise to rack the
circuit breaker from the Disconnect position to the Test
position.) If the racking crank is not of the “Captive” type,
constant inward pressure is required during racking to
maintain engagement with the racking mechanism.
3. With the circuit breaker in the Test position and
OPEN, de-energize control power to the circuit breaker.
Figure 1
shows the location of control power discon-
nects in a normal unit.
4. Perform the Spring Discharge Check, and verify that
the circuit breaker is OPEN and the closing spring indi-
cator shows DISCHARGED.
5. Insert the racking crank on the racking screw on the
front of the circuit breaker cell, and push in, as
described in step 2. Rotate the racking crank counter-
clockwise until the circuit breaker is in the Disconnect
position. The circuit breaker can now be removed from
the cubicle.
6. The circuit breaker is now free to be rolled out on the
floor using the handles as shown in
Figure 4
. The
wheels of the circuit breaker are virtually at floor level
(unless the switchgear is installed on a raised pad), and
one person should be able to easily handle the unit.
Removal from Upper Cell (Indoor and Shelter-Clad
Outdoor Switchgear)
- Removal of the upper circuit breaker
in a two-high assembly is similar to removal of a circuit
breaker from a lower cell, with several additional steps.
Figure 5
shows one of the two circuit breaker extension
rails being inserted into the fixed rails within the upper cell
of two-high switchgear equipment. The rails engage locking
pins in the fixed rails to secure them in position.
The procedure for removal of an upper circuit breaker is:
1. Open the circuit breaker.
2. If the circuit breaker is in the Connect position, insert
the racking crank on the racking screw on the front of
the circuit breaker cell, and push in. This action
operates the racking interlock latch.
Figure 3
shows
racking of a circuit breaker in the upper cell - the
process is similar for a circuit breaker in the lower cell.
Rotate the racking crank counterclockwise until the
circuit breaker is in the Test position. (If the circuit
breaker is in the Disconnect position, turn the racking
Figure 4:
Removal of Circuit Breaker.
Figure 3:
Racking Circuit Breaker in Switchgear.
