21
R E LI AG E A R® LV SG
LO W VO LTAG E S W I TC H G E A R
Compartments for future breakers
When specified, compartments may be supplied for
future addition of circuit breaker elements. These
compartments are fully equipped with cradles,
primary disconnects, and ancillary devices as
required (i.e. secondary disconnects, accessory
devices, etc.). The opening in the breaker
compartment door is closed with a bolted-on steel
plate to deter accidental contact with energized
electrical circuits (i.e. primary disconnect stab
tips). See Figure 27 and 28.
1. Quarter-turn latch
2. Steel plate (future cubicle door cover)
1. Future cubicle door cover
1. 24V power supply
2. Auxiliary summing ct
3. Voltage conditioners
4. Enclosed fuse block
• Mounting and wiring of additional metering,
relaying, and control devices requiring more
space than available in a standard instrument
panel or instrumentation compartment
(transition or auxiliary);
• Mounting and wiring of purchaser specified and/
or furnished devices (i.e. utility revenue metering
equipment, etc.).
Auxiliary sections may be 22-inch, 30-inch, or 38-
inch wide as required to accommodate the space
requirements. The compartment doors on the front
of the sections are hinged and latched in the same
manner as breaker compartment doors.
Generally, transition sections will be 22-inches wide
for close-coupling to transformers and "match and
line-up" to non-ABB equipment.
Power company metering requirements generally
require either a 38-inch or 49-inch wide auxiliary
section to accommodate the current transformers,
kilowatt-hour meters, demand meters, etc. as
required by their individual practices, tariff
schedules, and/or regulatory commissions.
Figure 29 is a front view of a typical
instrumentation compartment. Examples of
primary and secondary control protection in the
instrument compartment are shown in Figure 30.
Auxiliary/transition sections
Sections may be provided for any one or more
of several reasons including:
• Transition to a close-coupled transformer;
• Transition to "match and line-up" with existing
AKD-8/AKD-10/AKD-20 switchgear;
• Incoming cable or busway when a main
breaker section is not provided;
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27
Inside of Future breaker
compartment door
—
27
—
28
—
29
—
29
Auxiliary/transition
section (partial
front view)
—
28
Future breaker door cover
(pad-lockable ¼-turn
latch may be provided on
future breaker cubicles)
1
2
1
1
2
3
4