Eaton Magnum Air MWN-408 User Manual page 37

Spring Release - The spring release is an optional device
(Figure 3-34). It remotely closes the circuit breaker when
the coil is energized by a voltage input (Table 3-4). The
closing spring must be fully charged and the trip latch
reset (not held in the tripped position) for the SR to
operate. If these two conditions are not met the close
signal will be ignored until it is removed
and re-applied.
An optional Latch Check Switch (LCS) can also be
installed to delay application of power to the Spring
Release coil until the circuit breaker is "ready to close".
The LCS will not permit energization of the Spring
Release until the breaker is fully charged and the trip latch
is reset. Two versions of the LCS are available. One
version is wired internally to the Shunt Trip coil control
circuit. On the other version the LCS switch contacts are
brought out through the secondary contacts for
integration into external control schemes. Note
that placing the (externally accessible) LCS directly in
series with the ST coil is not recommended as this will
override the "anti-pump" feature of the electrical
charging/closing system.
Figure 3-34: Spring Release with Optional Latch Switch
Table 3-4: Spring Release Ratings
Control Operational
Voltages Voltage Range 70-
110%
24 Vdc 17-26 Vdc
48 Vdc 34-53 Vdc
110-125 Vdc 77-138 Vdc
220-250 Vdc 154-275 Vdc
110-127 Vac 77-140 Vac
208-240 Vac 146-264 Vac
1
Required for less than 200 ms
1812.900A
1
Inrush Closing
Power Time (ms)
Consumption
250 W 40
250 W 40
450 W 40
450 W 40
450 VA 40
450 VA 40
Undervoltage Release - The undervoltage release is an
optional device on both manually and electrically operated
circuit breakers (Figure 3-35). It opens the circuit breaker
when its supply voltage falls to between 35-60% of rated
voltage. If the release is not energized to 85% of its
supply voltage, the circuit breaker cannot be closed
electrically or manually (Table 3-5).
Auxiliary Switch - An auxiliary switch is an optional
device providing remote electrical indication if the circuit
breaker is open or closed (Figure 3-37). Up to 3 auxiliary
switches can be mounted in the circuit breaker. Each
switch has 2 normally open ("a") and 2 normally closed
("b") contacts for a total of 12 available contacts
(Table 3-6).
Figure 3-35: Undervoltage Release
Figure 3-36: Shunt Trip, Spring Release and Undervoltage
Release Installed
Magnum
37