Removing Of Cable Grommet On A Secondary Terminal Cover; Step Drill Procedure; Screwdriver Procedure; Appendix 5 - ABB TPU Series Instructions For Installation, Use And Maintenance Manual

Appendix 5

Removing of cable grommet on a secondary terminal cover

1) Step drill procedure

In case of use of a step drill, it is necessary to dis-
mount a secondary terminal cover to prevent a
damage of a transformer body. Maximal drill bit
size is 20 mm.
A drilled plastic part shall be fully fixed to avoid
any injuries. The pictures are for illustration pur-
pose only.
It is recommended to clear the edges of all new
holes immediately after drilling these holes. For
these purposes, a rasper or a knife can be used.
Cleaned secondary terminal cover can be
mounted back to a body of transformer.

2) Screwdriver procedure

It is recommended to use a screwdriver to punc-
ture a hole in a secondary terminal cover.
A screwdriver shall be placed to a weakened place
close to a pre-perforated ring. Two dimensions of
hole can be punctured.
1/ an inner diameter
2/ an outer diameter
If necessary, a plastic mallet can be used. The
plastic mallet shall be used with ease.
It is recommended to clear the edges of all new
holes immediately after puncturing these holes.
For these purposes, a rasper or a knife can be
used.
Note: Whole procedure must be realized with all
caution, to avoid damage of a secondary termi-
nal.
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