Siemens vacuum circuit breaker 38-3AH3 38 kV - Manual (Page 59)

Maintenance and
troubleshooting
Sub-assembly Item Inspect for
Primary power path Vacuum interrupter 1. Cleanliness.
2. Contact erosion. Note: Perform with
manual-spring checks.
3. Vacuum integrity. Note: Perform with
high-potential tests.
Primary disconnects 1. Burnt or damaged fingers.
2. Lubrication of contact surfaces.
Vacuum interrupter contact resistance 1. Record contact resistance with contacts
CLOSED and check at each maintenance
interval to monitor condition.
Vacuum interrupter operator mechanism Cleanliness 1. Dirt or foreign material.
Fasteners 1. Tightness of nuts and other locking
devices.
Manual-spring check 1. Smooth operation of manual charging,
manual closing and manual tripping.
Lubrication 1. Evidence of excessive wear.
2. Lubricaion of wear points.
Electrical controls Wiring 1. Mechanical damage or abrasion.
Terminals and connectors 1. Tightness and absence of mechanical
damage.
Close and trip solenoids, anti-pump relay,
auxiliary switches and secondary
disconnect 1. Automatic charging.
2. Close and trip with control power.
High-potential test Primary circuit-to-ground and between
primary disconnects 1. 60-second withstand 60 kV, 60 Hz
(85 kV dc).
Control circuit-to-ground 1. 60-second withstand 1.5 kV, 60 Hz.
Insulation Barrier and all insulating components 1. Cleanliness.
2. Cracking, crazing, tracking or other sign
of deterioration.
Table 6: Periodic maintenance and lubrication tasks
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