Installation; Grounding - ABB OVR-15 Instruction, Operation And Maintenance Manual

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6 Installation

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The OVR-15, 27 and 38 recloser LV unit can be
08 Provisions for
grounding connections
installed in a substation frame or pole-mounting
on LV cabinet
frame, or it can be mounted into a customer-
supplied structure. Regardless of the mounting
method, it is imperative that the LV unit be vertical,
leveled and securely fastened.
Before shipping from the factory, the OVR-15, 27
and 38 recloser LV control cabinets are tested as
part of a system. The HV unit and LV control cabinet
that were tested together must be installed
together as a set. The units must be properly
matched by the serial numbers listed on the rating
plates provided on each unit.
• All metal mounting frames and structures
must be commonly grounded to the
grounding grid at the installation site.
For proper operation of the electronic
components, the total impedance of the
grounding grid on site must be less than
one ohm (1 Ω)
• It is also mandatory to ensure that all
grounding connections to the welded star
grounding pad inside the LV cabinet are
always intact and secured.
• Be careful not to bend the cable beyond
a radius of 12 inches to avoid damage
to the cable.

6.1 Grounding

IMPORTANT
Always follow international, national, local and
company-specific regulations when grounding
the equipment.
All metal mounting frames and structures must be
commonly grounded to the grounding grid at the
installation site. Grounding is important to ensure
proper operation of all electronic components,
as well as to prevent penetration of EMC noise
and other transients into the sensitive electronic
circuits (SEL-751 relay, ACM, radios, etc.). Each
LV cabinet includes two stainless steel welded
grounding pads for grounding and an M8 stud
as shown in figure 8. For grounding, an 80 sq. mm
solid copper strip/equivalent is recommended.
For the proper operation of electronic components,
it is mandatory that the total impedance of the
grounding grid on site be less than one ohm (1 Ω).
It is also mandatory to ensure that all grounding
connections to the welded star grounding pad
inside the LV cabinet are always intact and secured.
Grounding terminal (M8)
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