GE AKR-30 Series Maintenance Manual page 75

SECTION 1 3-EC Trip Device {Cont.)
1 3.4 REVERSE CURRENT TRIPPING DEVICE
The device is enclosed in a molded
the right pole base similar to the series overcurrent tripping
device.
The reverse current tripping device (see Fig. 1 03) consists of
a series coli (2) with an jron core mounted between two pole
pieces (9), also a potential coli (7) connected across a constant
source of voltage and mounted around a rotary-type armature
( 1 0). Calibration spring (6) determines the armature pick-up
when a reversal of current occu rs .
as
As long the flow of current through the breaker is in the
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and is mounted on
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FIG. 1 03 ED-1 REVERSE CURRENT TRIPPING DEVICE
normal direction, the magnetic flux of the series coil and the
magnetic flux of the potential coil produce a torque which tends
to rotate the armature counterclockwise. The calibration spring
also tends to rotate the armature in the same direction. This
torque causes the armature to rest against the stop screw (12)
attached to a bearing plate on the right side of the device.
H the current through the series coil (2) is reversed, the ar­
mature ( 1 0) tends to move in the clockwise direction against the
restraint of the calibration spring (6). When the current reversal
exceeds the calibration setting, the armature revolves clockwise
causing the trip rod (3) to move upward engaging the trip paddle
(1 ), thereby tripping the breaker.
1 . Trip Paddle
2.
Series Coil
2A. Adjusting
28. Locking
3. Trip Rod
4.
Trip Crank
5. Setting Sealing
6.
Calibration Sp
Potential Coil
7.
8.
Calibration
9. Pole Pieces
Armature
1 0.
1 1 . Counter Weight
12.
Stop Screw
1 3. Mounting Screw
14.
Screw
Nut
Nut
.
Screw
ri
ng
Nut
75