Grounding Of The Bushing Flange - ABB GOE Series Installation And Commissioning Manual

4.12 Grounding of the bushing flange

Overview
The bushing flange must be grounded to the transformer tank. This prevents electrical discharge between the
bushing flange and the transformer tank under normal service conditions.
There are two alternatives.
DANGER!
Make sure that the grounding is correct. An unsatisfactory grounding can cause damage to
equipment, or death to personnel.
Procedure with a cone point set screw
1. Apply a large quantity of Mobilgrease 28 to the
cone point set screw (50).
2.
Install the cone point set screw (50).
End of instruction
Procedure with a flexible cable
1. Clean the contact surfaces.
58
CAUTION!
The quality of the cone point set screw
is important, stainless steel of A4-80
quality is recommended.
NOTE!
Or use a lubricant similar to
Mobilgrease 28.
NOTE!
The cone point of the set screw
penetrates the paint. This makes an
electrical connection between the
bushing and the transformer tank,
keeping them at the same potential.
Torque
M12: 40 Nm
Installation and commissioning guide
2750 515-1 EN, REV. 14, 2020-06-26