GE AKD-20 AR Installation And Maintenance Manual page 32

AKD-20 AR / Entellisys AR Low-voltage Switchgear
Section 4. Equipment Installation
Complete the Electrical Interconnections
After completing the mechanical connections between the
several sections of equipment, the electrical interconnections
should be completed. This includes the installation of splice
plates for the main bus bars, the neutral bus, and the ground
bus in addition to the control and metering circuits.
Figure 4.8 illustrates the general location of the buses that
must be spliced across the shipping splits.
WARNING: All switchgear equipment must be
adequately grounded for safety. Failure to ground the
equipment properly may result in serious injury.
Ground Bus Interconnections
The ground bus is mounted directly on the rear upright
channels in each vertical section. The ground bus is
commonly located in lower position but can be alternately
located near the upper portion of the upright channels.
A 4/0 AWG cable connector is located in the bottom of the
transition section (or in the incoming line compartment if a
transition section is not included) for terminating the
purchaser's cable connection to ground. The specific location
of the station ground connection is shown on the site floor
plan drawing and in the electrical drawings supplied with the
equipment. All grounding of the switchgear should be in
accordance with National Electrical Code.
Figure 4.9 illustrates the installation of the ground bus splice
plate across a shipping split. In addition to the bolted
fastening of the splice plate to the two ends of the ground
bus, self-tapping 1/4-20 bolts pass through the splice plate
and ground bus stubs, and thread into the equipment frame.
These bolts should be fastened with a torque of 7-9 ft.-lbs.
All bolted bus joints should be made using the proper torque
shown in Table A-1 in Appendix A. Torque Values of this
instruction manual.
WARNING: It is particularly important that the ground
bus be connected first since it provides an integral ground
for all the equipment. It must also be connected to the
station ground prior to proceeding with the installation.
Failure to provide an adequate ground prior to energizing
the equipment may result in serious injury and
misoperation of the equipment.
27
Courtesy of NationalSwitchgear.com
Figure 4.8 Typical locations of buses at shipping splits
Figure 4.9 Ground bus splice installation (plan view)
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