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6. Set the timer switches at 1 sec.
7. Turn on SW-1 suddenly. The digital timer
should read between 0.96 and 1.080 sec-
onds.
Tripping time = (timer switch setting "5%) + curve
value
Example using acceptance check values.
Set the timer switches to a value between 0.2 and 2
sec.
For timer switch setting = 1 sec. and multiple of pick-
up value = 100
If input current to the relay is 1 amp and pick-up set-
ting is at 10 mA then the "Multiple of pick-up value" is
100 (1 amp/10mA). Then from the curve (for timer
switch setting of zero), the time will be between 19
msec and 29 msec for the "Multiple of pick-up value"
of 100.
Tripping time = (1 sec. "5%) + (19 msec. to 29 msec.)
E. Timer
1. Connect the test circuit as shown in Figure
11 (b).
2. Set input voltage in 120 Vac and current at 1
amp.
3. Set the timer switches at 10 seconds.
4. Turn on SW-1 suddenly. The digital timer
should read between 9.5 and 10.5 seconds.
5. Repeat step #4 for 2 and 20 second settings.
The accuracy should be within 5%.
F. Trip Indicator
1. Short terminals 10 and 1 and adjust R to
obtain 0.5 amps (dc).
2. Remove the jumper between 10 and 1.
Close SW-2 and then close SW-1. The mag-
netic disc indicator should flip and show the
orange color.
3. Turn off SW-1 and SW-2. Push the reset
switch. The indicator should flip back and
show the black color.
8.
ROUTINE MAINTENANCE
All relays should be inspected periodically and all
settings and times of operation should be checked at
least once every year or at such other intervals as
may be indicated by experience to be suitable to the
particular application.
8.1. Calibration
The proper adjustments of the trimpots P1, P2, P3
and P4 have been calibrated by the factory and
should not be disturbed by the customer unless the
relay is out of calibration shown in the Acceptance
Test.
Before relay calibration, check the power supply
jumper's position on the bottom module for correct
rated dc voltage, as well as on the In-rush filter mod-
ule at the top of the relay.
1.
Trimpot P4
(a) Connect the test circuit as shown in Figure
11 (a) and connect a dc digital voltmeter
across TP4 (+) and TP5 (com).
(b) With Terminals 8 & 9 shorted and the rated
ac and dc voltages applied, adjust P4 until
the reading is close to 0.0 mV.
2.
Trimpot P2
Repeat steps #1(a) and #1(b) except remove
the dc voltmeter from TP4 to TP1. Adjust P2
until the reading is close to 0.0 mV.
3.
Trimpot P3
(a) With the connection of V (sig.) of the
phase angle meter at TP2 and the rated ac
and dc voltage applied. Adjust P2 for a
reading of -150 deg. (or +30 deg. at TP3).
(b) Change the test circuit connection from
Figure 11(a) to Figure 11(b) .
(c) Apply ac, dc voltages and ac current of 1
ampere. Adjust the phase shifter for cur-
rent leading voltage by +120 deg.
(d) Connect a dc digital voltmeter across TP1
(+) and TP5 (com). Adjust P3 to obtain a
reading of 0.0 ±0.5 mV.
(e) Adjust the phase shifter until the voltmeter
reads zero volts again. The phase angle
reading should be 300 ±2 deg.
4.
Trimpot P1
I.L. 41-252A
7
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