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Service information
242
NXAIR M
139-2021.9 / 07
25.4 Preventive maintenance
DANGER
Electric shock
Before any maintenance work is performed within primary compartments, it is to
make certain that the respective panel or panels are completely de-energized,
tagged or locked out and released for work in an authorized manner.
Disable remote control and automatic schemes.
De-energize all direct and back-feed power and control sources.
Disconnect all voltage and control power transformers.
Verify safe isolation from supply.
Earth the feeder in the respective panel or panels.
DANGER
Danger due to foreign objects
Serious switchgear damage and malfunctioning due to flashovers caused by
foreign objects.
Remove all foreign objects from the switchgear, e.g. tools, cleaning cloths
or lubricants.
NOTICE
Damage due to removal of greasing
Some parts and surfaces of the switchgear are greased for functioning.
Do not remove the grease from greased parts and surfaces.
Do not clean greased parts and surfaces.
If greased areas are dirty.
Clean the dirty area and grease again according to these maintenance
instructions.
NOTICE
Damage due to incorrect cleaning
Dust and loose pollutants can impair the functioning of the switchgear and lead to
damages. For cleaning, remove dust and loose pollutants precisely from the
switchgear.
Use vacuum cleaners and dry, lint-free cloths.
Do not
clean with compressed air or similar means.