First Level Maintenance Operations; Preliminary Operations; General Inspections And Cleaning; Circuit Breaker Connections And Connections Between Circuit Breaker And Switchboard - Allen-Bradley 140G-R Installation Instructions Manual

8.3

First Level maintenance operations

8.3.1

Preliminary operations:

- open the circuit breaker and make sure that the springs of the operating mechanism are discharged.
WARNING: disconnect the power circuit and auxiliary circuits and ground the terminals in a visible way on both
!
the supply side and load side.
8.3.2

General inspections and cleaning:

- Check to make sure that the device is clean. Remove any dust and traces of oil or grease with a clean, dry cloth (use a mild
detergent if necessary - A cleaning product such as Henkel's 273471 or equivalent can be used if there is a heavy coating of dirt).
- Make sure that the rating plates with the technical specifi cations of the apparatus are affi xed.
- The nameplate must be cleaned with a clean, dry cloth.
- Remove all traces of dust, mold, condensation and tarnish
- Make sure that there are no foreign bodies in the circuit breaker.
8.3.3

Circuit breaker connections and connections between circuit breaker and switchboard

- Remove any dust and dirt with a brush and dry cloth - use a mild detergent if necessary. Use a cleaning product such as Hen-
kel's 273471 or equivalent if there is a heavy coating of dirt.
- Make sure that there are no traces of localized overheating on the terminals. This problem is denoted by the change in the color
of the parts in contact. These parts are usually silvery in color.
- Make sure that the bolts of the terminal connections are tightened (M12 - 619.5 lb-in / 70 Nm).
WARNING: disconnect the power circuit and auxiliary circuits and ground the terminals in a visible way on both
!
the supply side and load side.
- Make sure that the control circuit and fi eld connection screws are well tightened in the terminal boxes (6.19 lb-in / 0.7 Nm).
Fig. 19
8.3.4

Circuit-breaker Cover and Side Guards disassembly

– Make sure the circuit-breaker has been disabled as described in sect. 8.1
– Open Clear Door (1) on the trip unit as shown in fi gure 19.
– Remove the Breaker Cover (2) by removing the four screws (3).
– Remove both the Side Guards (4) by removing the mounting screws (5).
4
5
1
3
2
Fig. 20
- If the undervoltage release is installed, disassemble the coil support and discharge the springs of the operating mechanism by
closing and opening the circuit breaker.
Fig. 21
DIR 1000682R0002 Version 03
1
3
3p
2
(14)
4
5
4p