Installation; Operation - GE IBCG51E21 Instructions Manual

around a stationary central core.
aluminum induction rotor is free to rotate in the
annular air gap between the poles and the core.
The poles are fitted with current operating, current
polarizing, and potential polarizing coils.
The principle by which torque is developed is
the same that of an induction disk relay with a
wattmetric element, although,
parts, the unit is more like a split-phase induction
motor.
The induction-cylinder construction pro-
vides higher torque and lower rotor inertia than the
induction-disk construction, resulting in a faster
and more sensitive relay.
A seal-in unit is
mounted
unit as indicated in Fig. 1. This unit has
its series its contacts in parallel with the
and
main contacts of the overcurrent unit, arranged in
such a manner when the main contacts close, the
seal-in unit picks up and seals-in around the
contacts. When the seal-in unit operates, it raises a
target into view which latches up and remains ex-
posed until manually released by pressing the button
located at the lower-left corner of the cover.
The location should be clean and dry, free from
dust and excessive vibration and well lighted to
inspection
The relay should be mounted on a
The outline
surface.
shown in Fig. 19.
The internal connection diagrams for the various
relays are shown in Figs. 3 to
are shown
is important for-the correct operation of
Type relays, the rotation specified in Figs.
9 and 10 must be adhered to. Unless mounted on
a steel panel which adequately grounds the relay
case, it is recommended that the case be grounded
through a mounting stud or screw
ductor not less
or its equivalent.
At the time of
inspected tarnished contacts, loose screws, or
for
other imperfections.
should be corrected in the
Courtesy of NationalSwitchgear.com
Ground Directional Overcurrent Relay Type
The cup-like
arrangement of
on the left side of the

INSTALLATION

testing.
vertical
panel drilling diagram is
Typical wiring
9 and 10. Since
a con-
B S gauge copper wire
the relay should
If trouble is found, it
described under
The directional unit contacts which control the
time overcurrent unit, are shown in Fig. 11. They
are of the low gradient type specially constructed to
minimize the effects of vibration. Both the stationary
and moving contact brushes are made of low gradient
material which, when subjected to vibration, tend to
follow one another, hence, they resist contact sep-
aration.
The contact d&l (A) supports the stationary con-
tact brush (B) on which is mounted a conical contact
tip (C). The moving contact arm
moving contact brush (E) on which is
ton contact tip
brush bears against the inner face of the moving con-
tact brush retainer (G).
stationary contact brush bears against the inner face
of the stationary contact brush retainer (Ii). The
stop screw mounted on the contact dial, functions
to stop the motion of the contact arm by striking the
moving contact brush retainer
stationary contact members have
stationary contact support
assembled together b means of a mounting screw (L)
and the two locknuts M).
CAUTION
Every circuit in the
auxiliary brush.
current circuits and other circuits
bars that the auxiliary brush be bent high enough
to engage connecting plug or test plug before
the main brushes do.
ondary circuits from being opened.'
Fig. Section of
ing Position of Auxiliary Brush
Before the relay is put into service, it should
be given a check to determine that factory adjust-
be
ments have not been disturbed. The time dial will
be set at zero before the relay leaves the factory.
It is necessary to change this setting in order to
open the time overcurrent unit contacts.
GEH-2032
supports the
end of the moving contact
Similarly, the end of the
the moving and
made contact.
and the contact
case has an
It is especially important on
shorting
This
Case Show-
but-
are
CT sec-
Q