GE Industrial Solutions EntelliGuard E Circuit Breaker - Manual (Page 27)

©2012 General Electric All Rights Reserved 27
1. Inspect the arc splitter plates and sides of the moldings
for signs of wear or damage. Replace as necessary.
2. With the circuit breaker in the ON position, check the
size of the gaps between the fixed and moving arcing
contacts.

If the gap is greater than 2.5 mm:
-
No evidence of contact damage: loosen the
fixed contact screw and adjust the gap to
2.5 mm. Retighten the screw (12 N m torque).
-
Evidence of excessive contact wear or damage:
Replace the fixed arcing contacts and set the
gap set to 2.5 mm.
 Even if gaps are within operating tolerance (1 mm
to 2.5 mm), always check contact screws for
tightness to 12 N m torque.
3. Assemble the arc chamber. Torque to 2 N m.
Circuit Breaker Main Mechanism Inspection
 Check the circuit breaker CLOSE and OPEN action both
manually and by remote means, if appropriate.
 Check all indicators for correct function.
 Check number of operations to the circuit breaker’s
specification.
Cassette Inspection

Ensure the base of the cassette is clear of debris.
 Prop open the shutters and inspect the cassette’s
installed contacts for excessive wear or damage.
 Check the carriage switch operation (if installed) while
racking the circuit breaker into and out of the
CONNECTED position.
Isolating Contacts Inspection
1. Remove the circuit breaker from the cassette housing
and place it on a suitable working surface.
2. Inspect the rear cluster contacts for signs of
overheating and wear.
3. Remove the cluster contacts using the special cluster
pliers.
4. Clean the isolating contacts and terminals with a soft,
clean cloth to remove any old grease or dirt.
5. Apply a thin film of red lube grease D50HD38.
Lubrication
CAUTION
PRODUCT DAMAGE
Do not lubricate Auxiliary Switch, Signaling Switches,
Coils, Motor and Secondary Disconnects.
Failure to comply with these instructions may result in
product damage.
Ensure all metal-to-metal friction surfaces are kept
lubricated:
1. Remove old lubrication and dirt.
2. Apply Molecote 4700.
3. Wipe off excess lubrication.