T EC H N I C A L A N D A P P L I C AT I O N G U I D E
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The circuit breakers have self-aligning, fully automatic
primary and secondary contacts allowing operators
to keep the door closed throughout the entire racking
operation, which maintains the arc-resistant protec-
tion of the switchgear. These features make SafeGear
easy to install, operate and maintain while making
safety a priority.
Unique racking system and interlocks
The racking system is unique and features a three-po-
sition closed door system for all circuit breakers. The
racking mechanism is integral to the circuit breaker,
so all moving parts can be inspected and maintained
outside the circuit breaker compartment and away
from energized primary parts. A solid stationary
ground contact engages the grounding contact of the
circuit breaker prior to the coupling of both the pri-
mary and secondary contacts and is continuous
during the racking operation.
The three racking positions are defined as follows:
• Disconnected: primary and secondary (control) con-
tacts are disengaged
• Test: primary contacts are disengaged; secondary
(control) contacts are engaged for in-cell breaker
testing
• Connected: primary and secondary (control) con-
tacts are engaged
The racking system includes all necessary interlocks
in compliance with ANSI/IEEE standards to assure
proper sequencing and safe operation. For improved
safety, the interlocking system prohibits operation of
the breaker while in an intermediate position and pro-
hibits insertion of an improperly rated breaker.
Secondary disconnect system
A dual (50-pin) self-aligning secondary disconnect
for control circuitry is provided as a standard fea-
ture. The female portion resides in the circuit
breaker module. The secondary contacts are re-
cessed and are touch safe. No manual connection
of secondary contacts is required.
Primary shutters
Primary shutters automatically cover the primary
contacts when the breaker is not in the connected
position. The shutters may be grounded metal or
optional Lexan material. Primary shutter opening
and closing is forced by the circuit breaker move-
ment, rather than relying on springs or gravity. An
integral interlock prevents opening of the shutter
when the circuit breaker is removed, and can be
padlocked for added safety.
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Compartment types
Circuit breaker compartment
SafeGear circuit breaker compartments are designed for maximum
operator safety by providing one large viewing window and automatic
latching, three-position closed door racking.
