TGW NBS 90 PolySort, Инструкция по установке, эксплуатации и обслуживанию

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NBS®90 PolySort & SP IOM
P/N: 1193974 Revision Date: 4/25/2019 Page 64 of 83
Motor Controls
Inspection (Semi-Yearly)
•
Before servicing or performing any work in the motor control
panel, disconnect and lockout the main incoming service. If
only the panel disconnect is off, the incoming side will still be
hot.
Excessive overheating is indicated by discoloration of components. Most often, these symptoms are a
sign of loose connections. If left uncorrected this can eventually cause arcing between components,
leading to destruction of the controls. It is normal to find the interior of the control cabinet very warm
when it is first opened.
The condition of contacts must be checked on all contactors and starters that show signs of
overheating. Make sure that they are free of dust and are not excessively pitted or burned. When
badly burned or worn, the contacts must be replaced.
In the course of inspecting contact condition, spring pressure should be checked. As contact surface
wears down, spring pressure can be lost because of the overheating. Contact spring resiliency can
usually be detected by fingertip pressure.
Check for faulty door gaskets especially when there are excessive deposits of foreign materials.
Particular attention should be given to conductive deposits because they can cause flashovers and
premature component failure when allowed to collect to any great extent. Either reposition or replace
defective gaskets and clean the control cabinet.
Check all overload settings on motor controls. Check for loose wiring and tighten as required.
Cleaning
When cleaning a control cabinet, it is best to use a vacuum cleaner rather than compressed air. A
vacuum cleaner removes rather than redistributes dust and dirt. Compressed air can damage and
displace relay contacts and springs.
WARNING
•
Avoid touching components until they have had time to cool.
Some may still be hot.
WARNING