8
Installation Checks and Initial Functional Tests
The automatic spring charging features of the circuit
breaker must be checked. Control power is required for
automatic spring charging to take place.
1. Open control power circuit by removing pullout fuse
holder shown in
Figure 1
.
2. Install circuit breaker end of split plug jumper (if
furnished) shown in
Figure 7
to the circuit breaker. The
plug jumper is secured by means of screws, over the
circuit breaker’s secondary contacts.
3. Install the switchgear end of the plug jumper shown in
Figure 8
to the secondary disconnect block inside the
switchgear cubicle. The jumper slides into place. The
plug jumper interconnects all control power and signal
leads (e.g., remote trip and close contacts) between the
switchgear and the circuit breaker.
4. Energize (close) the control power circuit disconnect
(Figure 1)
.
5. Use the Close and Trip controls
(Figure 2)
to first Close
and then Open the circuit breaker contacts. Verify
contact positions visually by observing the Open/Closed
indicator on the circuit breaker.
6. De-energize control power by repeating Step 1.
Disconnect the plug jumper from the switchgear first
and next from the circuit breaker.
7. Perform the Spring Discharge Check again. Verify that
the closing springs are discharged and the primary
contacts of the GMI circuit breaker are open.
Final Mechanical Inspections without Control Power
1. Make a final mechanical inspection of the circuit breaker.
Verify that the contacts are in the Open position, and
the closing springs are Discharged.
2. Check the upper and lower primary studs and contact
fingers shown in
Figure 9
. Verify mechanical condition
of finger springs and the disconnect studs.
3. Coat movable primary contact fingers
(Figure 9)
and the
secondary disconnect contacts
(Figure 9 and 22)
with
a light film of Siemens Contact Lubricant No. 15-172-
791-233).
4. The GMI vacuum circuit breaker is ready for installation
into its assigned cubicle of the metal-clad switchgear.
Refer to removal procedures and re-install the circuit
breaker into the switchgear.
5. Refer to the Switchgear Instruction Manual for
functional tests of an installed circuit breaker.
