1 3.4.1
ADJUSTMENTS
The only adjustment to be made on the reverse current de
vice is to make sure that the trip
rod
has a minimum overtravel
of 1 /32 in. beyond the point of tripping the breaker. This adjust
ment should have to be made only when an old device is being
replaced by a new one.
The new device will be factory adjusted
so
that the top end of
the trip rod (3) will extend 1 /2 in. above the top of the device
case, and no additional adjustments of the trip
rod
should be
re
quired. To obtain the proper 1 /32 in. overtravel, close the
breaker and proceed as follows:
1 . Loosen the locking nut. (28).
2. Manually lift the trip rod and vary the position of the ad
justing nut (2A), this establishing
the
position of the adjusting
nut where the breaker is just tripped.
NOTE:
Be sure to keep clear of moving breaker parts when
tripping the breakers.
3. With this position of the adjusting nut established, advance
the adjusting nut upward one and one-haH turns.
4.
Tighten the locking nut and the minimum 1 /32-in. over
travel of the trip rod should
be
obtained.
1 3.4.2
REPLACEMENT
After removing the wiring for the potential coil the reverse cur
rent device can
be
removed and replaced by following the pro
cedure outlined for replacing the series overcurrent device. See
Section 1 3.6 . For wiring, see Fig. 1 03.
1 3.5
SWITCHETTE FEATURE
The switchette is operated by the long-time delay function. Its
purpose is to provide a set of contacts that will close before an
overload occurs. This device will not trip the breaker on over·
load it will trip on instantaneous only.
The switchette feature is available only in
type
EC-1 devices.
The switchette is used in one pole and EC-1 trips in the other
poles. For the alarm to be effective in indicating the overload
before the other poles trip the breaker, the device must have
less time delay than the
other two poles; this is accomplished
by using
a lower characteristic on the alarm device than the
other poles or
settang
the alarm devices long time setting at
80%.
76
1 3.6
TRIP DEVICE REPLACEMENT
Overcurrent devices on AKR30
&
AKR50 breakers may
bA
dismounted by removing
the
fastening hardware at the rear
·
the breaker
and
withdrawing the device.
EC
devices, after
beia
...
unfastened as shown in Figures 1 04 and 1 05, and having the
clamps on the
case
in
the front
removed, may
be
lowered clear
of the breaker. You do not have to separate frames on these
breakers.
FIG.
104
DISCONNECTING EC COIL
FIG.
1
OS
DISCONNECTING EC FRAME
www
. ElectricalPartManuals
. com