Siemens 3AH37, Operating Instructions Manual

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Maintenance
9229 9992 176 0D 55
2013-07-08
Maintenance
Maintenance and servicing
The vacuum circuit-breaker 3AH37/38 is maintenance-free under normal operating
conditions. The maximum permitted mechanical operating cycle number is 10 000.
We recommend you carry out regular visual inspections all the same.
Cleaning
The insulating parts must be clean if their insulating capacity is to be guaranteed.
Wipe insulating parts and any outer circuit-breaker parts with a damp cloth. As a
cleaning agent, use only warm water with a mild, liquid household detergent added.
Special operating conditions
If the vacuum circuit-breaker 3AH37/38 is operated under unfavourable indoor
conditions that deviate from the normal operating conditions (frequent heavy
condensation, dusty air etc.), we recommend regular cleaning of the outer circuit-
breaker parts and renewing the corrosion protection, if applicable.
For this, only the following agents may be used on the individual functional parts of
the circuit breaker:
Lubricant:
DANGER
High-voltage - danger to life
Touching live parts is fatal or causes serious physical injury.
Before beginning maintenance work, note the five safety rules for high-voltage
equipment specified in EN 50110-1, namely:
• Isolate from the power supply*)
• Secure against reclosing
• Verify safe isolation from the power supply
• Earth and short-circuit
• Cover or cordon off neighbouring live parts
*
)
On the vacuum circuit-breaker, actuate the OPEN, CLOSE and OPEN
pushbuttons manually one after the other. This ensures that the vacuum circuit-
breaker is open and the closing spring is discharged.
Note
The vacuum circuit-breaker should be taken out of the switch cabinet or
switchgear for servicing.
Note
Joints and bearings that cannot be disassembled must not be washed out with a
detergent prior to work.
Bearings, sliding surfaces: Isoflex Topas L 32
Bearings and bearings of the auxiliary switch S1
that are inaccessible in terms of greasing: Shell Tellus Oil 32