Fixed Circuit Breaker; Circuit Breaker Operation - Eaton IZM97 Instruction Manual

Figure 2-12 Levering position indication

2-8 Fixed circuit breaker

The fixed-type circuit breaker differs from the drawout ver-
sion in that it has no levering device, primary disconnects,
and secondary disconnects (Figure 2-13). In addition, a fixed
circuit breaker does not have a standard feature to hold the
breaker in a trip-free position. Fixed circuit breakers can be
mechanically interlocked using either the optional key inter-
lock (that is mounted through the front panel) or with option-
al cable interlocks that operate on the tripper bar (Figure
3-1).
Circuit breaker terminals have holes for making bolted hor-
izontal primary bus connections. Adapters are available for
making vertical primary bus connections. Secondary con-
nections can be made through standard terminal blocks or a
special connector compatible with the drawout circuit break-
er's type secondary connector. Both secondary connection
devices are mounted at the top front of the circuit breaker.
The fixed circuit breaker frame has two mounting feet,
one on each side, to permit the fixed circuit breaker to be
securely mounted. Each mounting foot has two slotted
mounting holes that are used to bolt the circuit breaker
securely in place. Use either M10 or 3/8-inch bolts for this
purpose. Refer to the dimensional drawings referred to in
Section 5 "Fixed circuit breakers" for circuit breaker and bus
stab dimensions.
Refer to the circuit breaker weights in table 2-1 to ensure
that the panel on which a fixed circuit breaker is to be
mounted is capable of supporting the weight.

2-9 Circuit breaker operation

Circuit breakers should be operated manually and/or elec-
trically before they are put into service. This can be done
during the installation process or some later date prior to
New generation IZM97, 99 low voltage air circuit breaker instruction manual MN013010EN February 2020 www.eaton.com.cn
NOTICE
Section 2: Receiving, handling, and installation
Figure 2-13 Typical fixed circuit breaker
Horizontal
connection
Figure 2-14 Fixed circuit breaker with available vertical
adapter
startup. To check circuit breaker operation, follow the oper-
ational procedures outlined in Section 3 for both manually
operated and electrically operated circuit breakers.
Fixed circuit breaker dimensions
The standard fixed circuit breaker is supplied with horizon-
tally mounted primary connections (Figure 2-14). Optional
vertical primary adapters are available for different bus con-
figurations.
Mounting foot
Vertical
connection
11