AEG VB 40.5 User Manual page 20

prevent accidents, special care should be taken in the operation mechanism.
8-3 Disassembly and replacement of circuit breaker parts shall be carried out by AEG personnel or
corresponding trained personnel, especially during reassembly, necessary adjustment shall be made.
8-4 Maintenance of circuit breaker
a. The operation structure shall be inspected when the circuit breaker has been operated for 5 years
(from the day when the new equipment is put into operation) or when the circuit breaker operates for the
specified times (5000 times for the circuit breaker with 25kA and below, 4000 times for the circuit
breaker with 31.5kA, and 2500 times for the circuit breaker with 40kA)：
●
Cut off the energy storage power supply and operate the circuit breaker to close and open once to
release energy.
●
Check the grease condition of rolling or sliding bearing surface.
●
Check the correctness of each component function during electrical and mechanical action.
●
Do a comprehensive appearance inspection。
b. The operation structure shall be maintained after 10 years of operation (calculated from the day
when the new equipment is put into operation) or the operation times of the circuit breaker (25 kA and
less than 10000 times, 31.5 kA circuit breaker for 8000 times, 40kA circuit breaker for 5000 times):
●
Cut off the energy storage power supply and operate the circuit breaker to close and open once to
release energy.
●
Re apply grease to supporting shaft, rolling and sliding bearing.
●
Check the correctness of each component function during electrical and mechanical action.
●
Check the condition or looseness of fasteners installed at connecting rod, crank arm and supporting
rod.
●
During maintenance, it is important to check the parts which are subjected to high stress during
operation.
In case of replacement of parts, all fasteners shall be replaced.
Comprehensive review of operating mechanism.
8-5 After the circuit breaker has been running for about 5 years or when the operating mechanism is
under maintenance, the circuit breaker body should also be inspected. Especially when inspecting the
appearance, it is also necessary to check the contamination, damp and corrosion of the equipment
surface. Clean the dust on the surface of insulating parts with dry cloth, and then wipe all kinds of dirt
with silk cloth with household alkaline cleaning agent or safety cleaner (pay attention to whether the
detergent used is applicable to plastic and synthetic rubber materials), and do not use carbon
tetrachloride or trichloroethylene to wipe.
The minimum interval of the above inspection work shall be less than 5 years for the switchgear
operating in some special use occasions or under harmful environmental conditions (such as in the
environment with high pollution and heavy corrosive gas).
16