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P a g e 22
The circuit breaker secondary connection is automatically
connected to the enclosure secondary connectors when
the circuit breaker is moved from DISCONNECT to the
TEST position and remains connected until the circuit
breaker is returned to the DISCONNECT position.
Verify the secondary connection by observing the
alignment of the indicator slot with the front edge of the
secondary shroud. (See Figure 5-6). If the slot is not
aligned, pull the cell secondary arm toward you to make
the connection.
5-4.3 SECONDARY TERMINAL CONNECTIONS
VCP-Wind circuit breakers are supplied with two 30-point
pin type secondary control terminals. A number of points
are used for breaker operation with a number of spare
contacts for customer use. The terminals are located at
the upper left of the circuit breaker Figure (5-6). When
the breaker is in the TEST position, confirm
Secondaries are connected by checking the indicator
slot on the Manual Connect Bracket, it should be
beyond the metal shrouds outside edge surface Figure
(5-6).
5-4.4 UNDERVOLTAGE TRIP DEVICE
The under voltage trip device for VCP-Wind 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 under voltage trip device is available only
as an instantaneous type with rated voltages of 48VDC, 1
25VDC, 250VDC 120VAC and 240VAC.
Table 5.1 Circuit Breaker Timing
Event
Closing Time
(From Initiation of Close
Signal to Contact Make)
Opening Time
(Initiation of Trip Signal
to Contact Make)
Reclosing Time
(Initiation of Trip Signal
to Contact Make)
Milliseconds (maximum)
75
45
190
For a basic understanding of the operation of the
under-voltage trip device refer to the specific items
identified in Figure 5-9 and the following operation
description.
1. With the circuit breaker closed and sufficient
voltage on the Under voltage 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 Under voltage 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.
Figure 5-6 Secondary Plug Shown Mounted on Top of
Drawout Circuit Breaker (top) & in Mini-Mod (bottom)
I.B. 70A2580H02
Effective November 2012
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