UFC 3 -520-01
June 10, 2002
Secure switchgear in accordance with the manufacturer's instructions.
Support cable routed to the switchgear to minimize forces applied to conductor
Do not route piping containing liquids, corrosive gases, or hazardous gases in
the vicinity of switchgear unless suitable barriers are installed to protect the switchgear
from damage in the event of a pipe failure. Do not locate switchgear where foreign
flammable or corrosive gases routinely and normally are discharged.
Do not use switchgear enclosure surfaces as physical support for any item
unless specifically designed for that purpose. Do not use enclosure interiors as storage
areas unless specifically designed for that purpose.
Ground metal instrument cases.
Place a safety sign on any cubicles containing more than one voltage source.
Install switchgear with clearances stated in paragraph 8 -1. Enclosed
switchgear rooms should have at least two means of egress, one at each extreme end
of the area, not necessarily in opposite walls. One door can be used when required by
physical limitations if means are provided for unhampered exit during emergencies.
Doors must swing out and be equipped with panic bars, pressure plates, or other
devices that are normally latched, but open under simple pressure.
Locate switchboards that have any exposed live parts in permanently dry
locations and accessible only to qualified persons.
Circuit breakers must clearly indicate whether they are in the open (off) or
closed (on) position.
Where circuit breaker handles on switchboards are operated vertically rather
than horizontally or rotationally, the up position of the handle must be the closed (on)
Clearly and permanently mark all circuit breakers to show the purpose of
Refer to NEMA PB 2.1, General Instructions for Proper Handling, Installation,
Operation, and Maintenance of Deadfront Distribution Switchboards Rated 600 Volts or
Less, for installation guidance. This NEMA standard also provides practical guidance
regarding energization of the new installation.
Place switchboards as close as possible to the center o f the loads to be
HIGH VOLTAGE SWITCHGEAR . Although high voltage levels might be
available at exterior substations, high voltage switchgear is less commonly used for