24
New generation IZM97, 99 low voltage air circuit breaker instruction manual
MN013010EN February 2020 www.eaton.com.cn
Section 4: Accessory devices
Accessory viewing windows
Section 4: Accessory devices
A variety of accessory devices are available for use with the
circuit breakers. Unless otherwise stated, they are all consid-
ered optional devices in the sense that they are not provided
as standard on a manually operated circuit breaker. Available
accessories are identified here and discussed in general
terms. For more detailed information and/or installation
instructions, refer to individual instruction leaflets dedicated
to the accessories.
The circuit breaker accessories are designed to fit all frame
sizes.
The accessories fall into one of three categories:
• Plug-in electrical
• Internal electrical
• Mechanical
4-1 Plug-in electrical accessories
There are four plug-in electrical accessories. Three can be
viewed for identification by name and rating through view-
ing windows located in the right front of the circuit breaker
(Figure 4-1). All four are plug-in type and can be factory
installed or field installed.
The four plug-in accessories are:
• Shunt trip (ST)
• Spring release (SR)
• Undervoltage release (UVR)
• Auxiliary switch (AUX)
Shunt trip—The shunt trip is an optional device on circuit
breakers (Figure 4-2 and Figure 4-3). It opens the circuit
breaker instantaneously when its coil is energized by a
voltage input (Table 4.1). A total of two shunt trips can be
mounted on a circuit breaker.
Table 4.1 Shunt trip ratings
Control
voltages
Operational voltage
range 70-110%
Inrush power
consumption
Opening
time (ms)
24 Vdc
48 Vdc
110-125 Vdc
220-250 Vdc
110-127 Vac
208-240 Vac
17-26 Vdc
34-53 Vdc
77-138 Vdc
154-275 Vdc
77-140 Vac
146-264 Vac
250 W
250 W
450 W
450 W
450 VA
450 VA
35
35
35
35
35
35
Required for less than 35 ms.
Figure 4-1 Through-the-window electrical accessories
Figure 4-2 Shunt trip with cutoff switch
Figure 4-3 Shunt trip switch installed