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GEK-34055
PICK UP
TESTS
With the unit connected for high range operation (parallel connections) and the target in the " Down"
t
;ition, check the pickup at the maximum calibration mark: the pick up should be within the limits in
1dble
X.
TABLE X
TARGET AND SEAL-IN UNIT
The target and seal-in unit has an operating coil tapped at
0. 2
and
2.0
amperes. The relay is shipped
from the factory with the tap screw in the lower ampere position. The tap screw is the screw holding
the rjght hand stationery contact. To change the tap setting, first remove one screw from the left
stationary contact and place it in the desired tap. N ext remove the screw from the undesired tap
place it on the left hand stationary contact where the first screw was removed. See Figure
2.
This pro
cedure is necessary to prevent the right hand stationary contact from getting out of adjustment. Screws
should never be in both taps at the same time.
PICK-UP AND DROPOUT TEST
1.
Connect relay studs
1
and
2
(See Internal Connections Diagram) to a D.C. source, ammeter and load
box so that the current can be controlled over a range of
0.1
to
2.0
amperes.
2.
Turn the time dial to the
ZERO
TIME
DIAL
POSITION .
1.
Increase the current slowly until the seal-in unit picks up. See Table XI .
Move the time dial away from the ZERO TIME DIAL position, the seal-in unit should remain in the picked
t
up position.
Decrease the current slowly until the seal-in unit drops out. See Table XI.
TABLE XI
TAP
PICK-UP
DROPOUT
CURREN T
CURREN T
0.2
0.15 - 0.195
.05
OR
MORE
2. 0
1.50 - 1.95
. 55
OR toK>RE
IN STALLATION TESTS
The following tests are to be performed at the time of installation.
TIME OVERCURRENT UNIT
1.
Set tap screw on desired tap.
Using the test circuit in Figure
13,
apply approximately twice tap value until contacts just close.
Reduce the current until the light 1n series with the contacts begins to flicker. This value of current
is defined as pick up and should be within
5%
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.
TARGET AND SEAL-IN UNIT
Make sure that the tap screw is in the desired tap.
Perform pick up and drop out tests as outlined in the Acceptance Test Section.
10
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