Electric Lockout Device; Bell Alarm; Bell A Larm; Operation - GE AKR-30 Series Maintenance Manual

SECTION 7 -Breaker Maintenance (Cont.)
3. Check resis t ance of the disconnected undervoltage
device. See Table 5 for values.
See i nstruction Sheet G EH-4545 for more detai led infor­
mation, i ncluding schematic diagrams and circuit descrip­
tion.
The undervoltage device must be calibrated through the
time-delay unit after the device pick up has been adjusted.
A .008 inch minimum closed gap m ust exist between the ar­
mature and magnet as shown i n Fig. 32C. Refer to Section
7.8.3 and Table 24.

7 . 1 0 ELECTRIC LOCKOUT DEVICE

The electric lockout device uti l izes an undervoltage
device to keep the breaker from resetting its mechanism if
the breaker is open and the undervoltage device coil is not
energized. The breaker thus cannot be closed unless
voltage is on the. coil . Once the breaker is c losed, loss-of
voltage will not trip the breaker because, in the closed posi­
tion, a mechanical link is used to hold down the armature of
33.
the device. See Fig.
means of electrically interlocking two breakers so that they
cannot be c losed at the same time. Each undervoltage coi l
may be wired in series with a " B " auxiliary switch contact
on the other breaker for cross-interlock purposes.
On each breaker havin g an electric lockout, an arrange­
ment is made wh ich will al low breaker closing with the coil
de-energized. This is provided to al low "start-up': on "dead"
34
systems. Fig ure shows this device. The push s lide
shown is located in the opening in the lower part of the
escutcheon. This breaker door m ust be opened to gain
access to it.
(
-
/
FIG. 34 - ELECTRIC LOCKOUT BY-PASS
26
This arrangement provides a
MA I N SHAFT
( BREAKER CLOSED)
/- _ -- --/_ __ _
.·
.
\
�-.
"'-
'•
. .
''--- ' _I .
· �
FIG. 33 - ELECTRIC LOCKOUT DEVICE

BELL ALARM

7 . 1 1
Th is device is used to g ive a remote i ndication of the
breaker having tripped open through the , action l of one of
its automatic protective devices. It wi l l not be activated by
manual tri pping or the action of the shunt trip. A remotely
mounted protective relay energizing the shunt trip will there­
fore not result i n the remote alarm action.
The bel l alarm circuit may be turned off by pushing in the
manual trip or by energizing the shunt trip. In the latter case,
a normally open contact of the bel l alarm switch m ust be
wired in parallel with the "A" auxiliary switch contact in the
shunt-trip circuit. Closing the breaker will also turn off the
alarm.
The bel l alarm device may be equipped with a lockout
link which will lock the breaker open unti l the bel l alarm
device is reset.
The bel l alarm is not a standard device and is suppl ied
only when specified on the breaker order.
7.1 1 .1

OPERATION

Referring to Fig. 35: the bel l alarm mechanism is ac­
tivated by a cra n k which is assembled to the breaker's main
shaft. When the breaker opens, a pin attached to this crank
moves the alarm link against the switch and locklever (if
provided). This activates the switch contacts. It also moves
the locklever adjustment screw against the trip shaft paddle
keeping the breaker trip free.
LATCH ENGAGEMENT
POINT
FIG. 35 - BELL ALARM DETAILS
SWITCH