Maintenance
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2021-11-15
Maintenance
Maintenance
The SION
®
vacuum circuit-breaker is maintenance-free under normal service con-
ditions (up to rated current). We do, however, recommend you carry out regular
visual checks. The highest permissible mechanical operating cycle number is:
• 10 000 Operating cycles: Maintenance-free
• 30 000 operating cycles: When maintenance is performed by Siemens author-
ised personnel.
Maintenance after 10 000 operating cycles
Preliminary work
• Prior to starting work on the vacuum circuit-breaker, observe the local safety
regulations for high-voltage devices and the "5 safety rules" as per EN 50110-1.
• Switch off the supply voltage and secure against reclosing.
• On the vacuum circuit-breaker, actuate the OPEN, CLOSE and OPEN pushbut-
tons manually one after the other. This ensures that the vacuum circuit-breaker
is open and the closing spring is discharged.
Special operating conditions
If the vacuum circuit-breaker is operated under unfavourable conditions indoors
(heavy and frequent condensation, dusty air, etc.), we recommend cleaning the in-
sulating parts and possibly the outer parts of the circuit-breaker more regularly.
Cleaning
Insulating parts
The insulating parts must be clean if their dielectric strength is to be guaranteed.
Rub insulating parts with a moist cloth.
As a cleaning agent, use only warm water with a mild, liquid household cleaner add-
ed and leave to dry.
Joints and bearing points
For joints and bearing points that cannot be disassembled, only wipe off with a dry,
lint-free cloth.
Under no circumstances may these joints and bearing points be cleaned with clean-
ing agents or water!
Service life of the vacuum interrupters
If switching operations occur frequently under overload or short circuit, the service
life of the vacuum interrupters may be ended prematurely.