Zakład Wytwórczy Aparatów Elektrycznych Sp. z o.o.
17
b) General inspection:
•
Perform the complete set of activities disrobed at ‘Periodic inspection’;
•
Clean all moving parts;
•
Measure the voltage drop of the disconnector main circuits at current I=100A DC
3)
;
•
Check dimensional compliance of the disconnector with the dimensional drawing, in particular insula-
tion gaps and spaces between live parts;
•
Check the condition of anti-interference screens (if installed);
•
Check technical condition of insulators
4)
;
•
Check the operation and condition of arcing contacts (if installed)
5)
;
•
Check earthing of the disconnector bases.
1)
When assessing condition of the disconnector contacts, check if the silver coating surfaces have not been
damaged permanently.. If necessary, replace damaged contacts with new ones.
2)
In case of thermal tests, the permissible temperature values are given in Table 14 of the PN-EN 62271-1:
2018-02 standard should be adopted as a criterion for assessing the correct operation of the disconnector.
3)
In case of measuring the voltage drop of the main circuit of a disconnector not connected to the busbar sys-
tem, the acceptable values indicated in the factory test report of the finished product should be taken as the
criterion for assessing the correct operation of the disconnector. In the case the disconnector is connected to
the busbar system, the voltage drop should not be exceeded 250 µΩ.
4)
When assessing the condition of insulators, it is necessary to check if there are no losses or damage to the insula-
tors, with particular emphasis on the surface of the shade. If necessary, replace damaged insulators with new ones.
5)
When assessing the condition of the arcing contacts, it is necessary to check whether there are no cavities or
pits on the contact surfaces. If necessary, replace damaged contacts with new ones.
5.3. Spare parts and recommended service materials
The use of high quality components and exploitation experience indicate long liveness of disconnectors (about
40 years). If the disconnector is damaged due to improper assembly or operation, it is possible for the manu-
facturer to repair it for a fee. Disconnector type ONIII does not possess parts, which should be replaced during
normal operation in service life.
For disconnectors maintenance, materials listed below have to be used:
a) WHITE PHARMACEUTICAL PETROLEUM JELLY (acid-free) used for lubrication electric contacts (earth-
ings, contacts of HV switches),
b) LUBRICANT for bearings, for example LT4 or similar, used for lubricating ball joints.
