tt
GEK-49861
(b) Make
the
test
connections
shown
in
Figure
31
for
the
particular phase being tested.
(The test connection shown in
Figure 24 may also be used. )
(c) Adjust the load box until the ammeter indicates the desired
test current (IT) .
See Table XIII for the recommended test
current for a desired reach.
TABLE XIII
RECOMMENDED TEST CURRENT
5 AMPERE RATED RELAY
1 AMPERE RATED RELAY
RECOMMENDED
RECOMMENDED
BASE REACH TAP
MINIMUM
BASE REACH TAP
MINIMUM
TEST CURRENT
TEST CURRENT
0.1
20tt
0.5
4tt
0.2
20tt
1.0
4tt
0.4
10tt
2.0
2
0.75
8
3.75
1.6
1.5
4
7.5
0.8
3
2
15.0
0.4
(d) Adjust the phase angle for the nominal base reach angle of
85° .
(e) Observe the waveform at the following test point (on OS card)
with an oscilloscope.
1)
"AOUT" for phase pair A-B
2)
"BOUT" for phase pair
B-C
3)
"COOT" for phase pair C-A
(f) Lower the voltage V to the value given in equation (2) below:
wher e
100
VT =2Xl X Z X
-
T
Rl
T
test curr ent in amperes RMS
restraint voltage setting in percent
pickup voltage at the base reach angle
in volts RMS
base reach tap in ohms
(2)
tt
VT should not be greater than 110% of rated voltage.
If VT is
greater, reduce IT until VT is correct.
20
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