Operation; Connections; Target And Seal-In Unit; Inspection - GE IBCG51M A Series Instructions Manual

CONNECTIONS

The internal connection diagrams for the various relays are shown in Fig. 5 to 9.
l
Typical external wiring diagrams are shown by Fig. 10, 11 and 12.
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 with a conductor
not less than #12 B&S gage copper wire or its equivalent.

INSPECTION

At the time of installation, the relay should be inspected for tarnished contacts,
loose screws, or other imperfections. If any trouble is found, it should be corrected
in the manner described in the section on SERVICING.

CAUTION

Every circuit in the drawout case has an auxiliary brush.
important on current circuits and other circuits with shorting bars that the auxiliary
brush be bent high enough to engage the connecting plug or test plug before the main
brushes do. This will prevent CT secondary circuits from being opened. Refer to
* Fig. 21.
Before the relay is put into service, it should be given a check to determine that
factory adjustments have not been disturbed.
the relay leaves the factory.
to change this setting in order to open the time overcurrent unit contacts.
following tests are suggested:

TARGET AND SEAL-IN UNIT

1. Make sure that the tap screw is in the desired tap.
2. Perform pickup and dropout tests as outlined in the

TIME OVERCURRENT UNIT

1.
Set tap screw on desired tap.
approximately twice tap value current until the contacts just close. Reduce the
current until the light in series with the contacts begins to flicker. This value
of current should be within five percent of tap value.
2. Check the operating time at some multiple of tap value. This multiple of tap
value may be five times tap rating or the maximum fault current for which the
relay must coordinate. The value used is left to the discretion of the user. Use
*
the test circuit shown in Fig. 23.
*Indicates Revision
GEK-49822

OPERATION

The time dial will be set at zero before
If the setting has not been changed, itwill be necess;;;
Using the test circuit in Fig. 22, apply
18
It is especially
ACCEPTANCE TEST section.