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ed by non-sinusoidal wave forms.
TIME OVERCURRENT UNIT
Rotate the time dial slowly and check by means of a lamp that the contacts just close at the zero
time dial setting.
Where the contacts just close can be adjusted by running the stationary contact brush in or out
by means of its adjusting screw.
With the contacts just closing at No. 0 time setting, there should be sufficient gap between the
0
stationary contact brush and its metal backing strip to ensure approximately 1/32" wipe.
The minimum current at which the contacts will just close is determined by the position of the tap
screw in the tap block at the top of the relay.
When changing the current setting of the relay while in the case, remove the connection plug to short
the current transformer secondary circuit.
current and then replace the connection plug.
The pickup of the unit for any current tap setting is adjusted by means of the variable resistor in
the phase-shifting circuit.
various tap settings to be obtained.
contacts just closed.
the factory to close its contacts from any time dial position at a minimum current within five per cent
of the tap setting.
PICKUP TEST
c
Set the relay at the 0.5 time dial position and 2.0 amp tap.
13, the main unit should close its contacts within
TIME TEST
Set the relay at the 5.0 time dial position and 2.0 amp tap. Using the test connections of Figure 13
and applying 5 times tap current (10.0 amp ), the relay should operate in 0.9 2 seconds +0.03 seconds.
IN STANTAN EOUS UN IT
Make sure that the instantaneous unit is wired for the range in which it is to operate (see Internal
Connections Diagram Fig. 5 or Fig.
possible, use the higher range, since the higher range has a higher continuous rating.
0
SETTING THE INSTANTAN EOUS UN IT
L � osen th � locknut and turn the pole piece toward the desired setting.
pole p1ece up 1ncr � ases the
current slowly unt1l the un1t p1cks up.
pick up value is obtained.
CAUTION :
This screw should be held securely in its support.
This adjustment also permits any desired setting intermediate between the
Further adjustment of this setting is seldom
The unit resets at 85 percent of the minimum closing value.
7)
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pic
up, turning the pole piece down decreases the pick up.
.
Once the desired pick up value is reached, tighten the locknut.
THE I N STANTAN EOUS UN I T I S RATED 1.5 TI M ES MI N I MUM PICKUP.
LON G AS I T MAY DAMAGE THE UN I T.
GEK-34 0 55
N ext, screw the tap screws into the tap marked for the desired
The control spring is prewound approximately 660 degrees with the
±2%
of tap v alue current(l.9 6-2.04 amp.).
and connected as indicated in Test Circuit Figure 13.
It may be necessary to repeat this operation until the desired
9
•. ---��--- ---�--
·
required.
The unit is adjusted at
Using the test connections of Figure
See Figure 2.
Bring up the
DO N OT LEAVE THE CURREN T ON TOO
---·-· · ---- -
Whenever
Turning the
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