Replacement Parts
ITEMS
DESCRIPTION
EATON STYLE NUMBER
UNDERVOLTAGE FIELD INSTALLATION KIT
& INSTRUCTIONS (QUICK DISCONNECT)
48Vdc
125Vdc
250Vdc
120Vac
240Vac
691C274G01
691C274G02
691C274G03
691C274G04
691C274G05
UNDERVOLTAGE FIELD INSTALLATION KIT
& INSTRUCTIONS (RING TERMINALS)
48Vdc
125Vdc
250Vdc
120Vac
240Vac
8794C81G01
8794C81G02
8794C81G03
8794C81G04
8794C81G05
WARNING
BEFORE ATTEMPTING THIS INSTALLATION, VERIFY CIRCUIT
BREAKER IS OPEN, CLOSING SPRINGS ARE DISCHARGED
AND CONTROL POWER IS DISCONNECTED.
Undervoltage Trip Device
The undervoltage trip device for VCP-W circuit breakers
is an electromechanical device that operates to open the
circuit breaker at 30% or less of the voltage rating of the
trip coil. The device does not open the circuit breaker at
values above 60% of the voltage rating of its trip coil. It
may operate, however, to open the circuit breaker when
the voltage across the trip coil is greater than 30%, but
less than 60% of the voltage rating of its trip coil. The
circuit breaker can be closed as long as the voltage to
the trip coil is maintained at 85% or above the rated
level. The undervoltage trip device is available only as
an instantaneous type with rated voltages of 48Vdc,
125Vdc, 250Vdc, 120Vac and 240Vac.
For a basic understanding of the operation of the
under-voltage trip device refer to IB131006EN and the
following operation description.
1. With the circuit breaker closed and sufficient voltage
on the Undervoltage Trip Device coil, the moving
clapper (1) is held to the stationary yoke (2) by the
magnetic force produced by the coil (3) against the
extension springs (4) pulling the moving clapper apart
from the yoke.
2. The moving clapper is connected to the mechanism
Trip D Shaft Lever (5) by a slotted link (6).
3. When the voltage to the Undervoltage Trip Coil goes
down as described earlier, the extension springs force
overcomes the reduced magnetic force and pulls the
moving clapper up. The slotted link in turn upsets the
Trip D Shaft and the circuit breaker trips open.
4. As the circuit breaker opens, the reset lever (8)
connected to the pole shaft lever (7) operates to reset
the moving clapper. As long as the circuit breaker
remains open, the reset lever holds down the moving
clapper to the yoke.
5. When the circuit breaker closes, the reset lever
moves away from the moving clapper. If the Under-
voltage Trip Device coil has at least 85% of the rated
voltage applied, the moving clapper is held to the
yoke by the magnetic force, even though the reset
lever has moved up.
Component
Installation
Installing an undervoltage trip device on a 150VCP-W25 mechanism.
12
EATON
|
Visual Instruction Booklet Essentials | 150VCP-W 25kA 1200A | January 2017
