Specifications

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Switchboard Construction Switchboards typically consist of a service section with a
main circuit breaker or main fusible switch and one or more
distribution sections. The service section can be fed directly
from the utility transformer. In addition to the main disconnect,
the service section usually contains utility or customer metering
provisions.
Service
Section
Distribution
Section
SB1, SB2, SB3, and RCS SB1, SB2, and SB3 switchboards have been designed to
Switchboards simplify system layout and reduce installation cost. They are
built to Underwriter’s Laboratory (UL 891) and National
Electrical Manufacturers Association (NEMA PB-2) standards
and provide rugged construction and service flexibility.
SB1 switchboards are designed fit in limited floor space.
Through-bus ratings up to 2000 amps at 600 VAC are available.
The main protective devices are front-connected. All sections are
rear aligned so that the switchboard can be installed against a
wall.
SB2 main protective devices and through-bus are rated up to
4000 amps at 600 VAC. The rear of all sections align as standard.
Front and rear alignment is available as an option.
SB3 switchboards offer the greatest variety of options and are
available with a main bus rating up to 6000 amps at 600 VAC.
The rear of all sections align as standard. Front and rear
alignment is available as an option.
RCS (rear-connected) switchboards
differ from the SB1, SB2,
and SB3 design primarily in the distribution section, which uses
individually mounted branch feeders. Because of the mounting
method, access to the outgoing cable terminals must be from
the rear of the RCS section. RCS switchboards are available with
a main bus rating up to 6000 amps at 600 VAC.