Page
8
NOTICE
If the breaker is levered out from the TEST position
to the REMOVE position with the closing springs
charged, a trip free closing operation automatically
takes place, but the breaker contacts
do
not close.
2-6 DRAWOUT DUMMY ELEMENT
A dummy element consists of a drawout frame or truck
with disconnecting contacts and connecting links
between the upper and lower terminal on each pole.
When inserted into a compartment, it bridges the upper
and lower stationary disconnecting contacts
in
each
phase. This makes it the equivalent to an isolating dis-
connecting switch.
IT MUST BE EMPHASIZED THAT A DUMMY ELE-
MENT IS NOT A BREAKER. IT HAS NO CURRENT
BREAKING ABILITY WHATSOEVER. The dummy ele-
ment is almost always key interlocked with a breaker
or
other load interrupting device to insure that it will be iso-
lated or carrying NO current before it can be levered to
the DISCONNECT position.
Dummy elements require the same size compartment
as an equivalent Type DSll breaker of the same frame
size.
2-7 FIXED CIRCUIT BREAKER
The Type DSll Fixed Circuit Breaker differs from the
drawout version in that it has no levering device, primary
disconnects and secondary disconnects. A fixed circuit
breaker does not have a padlock feature to hold the
breaker
in
a ''trip-free" position. To insure the proper
sequence of operation between two or more breakers, a
key interlock is mounted in the levering device location.
The breaker stabs have holes for bolting to primary bus
connections. Rear mounted terminal blocks serve as
secondary contacts. The basic breaker frame is modi-
fied to permit the fixed breaker to be mounted on a
panel (Figure 2-5).
l.B.
694C694-02
Figure
2-5
Typical Fixed Type OSI/ Circuit Breaker
Effective
07
/97
Courtesy of NationalSwitchgear.com
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