I.L. 40-385.5
A-11
VLN = 40
PANG = 75
Z1P = 10 (or Z2P = 20) X = 45
1.4.2
Condition OSB1 = OSB2 = OSBP = YES
Change the OSB setting from NO to YES and RT =
4, RU = 8.
Step 1.
Change the LED to metering mode with
the display of OSB = NO.
Step 2.
Apply a current IF of 2.7A
±
5% suddenly.
The display should show OSB = YES. This
means the input power swing is inside the outer
blinder (2IBO). Repeat this test for I
F
= 4A and
4.5A. The display should show OSB = YES be-
cause the power swing is within two blinders
(2IBO and 2IBI).
NOTE: The load restriction logic is not included
in this relay. the relay will trip after tim-
ers (OSTM + T2P) time out, e.g., 1300 ms.
Step 3.
Apply IF of 5.25A suddenly (5% above the
calculated value). The relay should trip with a dis-
play Z1P = ABC. The trip time should be
<2 cycles.
A computer controlled test unit is required
for the following test from step 4 to step 6
Step 4.
OS and OSOT1 Timers (50/OSTM and
OSTM/0).
(a) Use a computer to set the test sequence as fol-
lows:
State #1
State #2
State #3
V
a
= 70
∠
0
°
V
a
= 40
∠
0
°
V
a
= 40
∠
0
°
V
b
= 70
∠
-120
°
V
b
= 40
∠
-120
°
V
b
= 40
∠
-120
°
V
c
= 70
∠
-120
°
V
c
= 40
∠
-120
°
V
c
= 40
∠
-120
°
I
a
= 1
∠
0
°
I
a
= 3.5
∠
-45
°
I
a
= 6
∠
-45
°
I
b
= 1
∠
-120
°
I
b
= 3.5
∠
-165
°
I
b
= 6
∠
-165
°
I
c
= 1
∠
120
°
I
c
= 3.5
∠
75
°
I
c
= 6
∠
75
°
T1 = 50 cycles
T2 = 4 cycles
T3 = 36 cycles
T1, T2 and T3 are the duration time of state #1,
#2 and #3, respectively. Set the timer start at
state #3. The relay should trip in 500 ms with a
target of Z1P – ABC.
(b) Change T3 from 36 cycles to 24 cycles. Repeat
the test. The relay should not trip.
(c) Change T2 from 4 cycles to 2 cycles. The relay
should trip in 2 cycles with a target of Z1P –
ABC. Reset T2 = 4 and T3 = 36.
Step 5.
Timer 200/OSTM Test. Change the set-
ting of RT from 4 to 7.
(a) Set T2 = 10 cycle in State #2. Repeat the test
4(a). The relay should trip in 2 cycles.
(b) Set T2 = 15 in State #2. Repeat the above test.
The relay should trip in 500 ms with a target of
Z1P – ABC.
Step 6.
OSOT2 Timer (OSTM/0).
(a) Change the test sequence by deleting the State
#3 shown in Step 4. Change T2 = 100 cycles,
and RT = 7. Set the timer start at State #2. The
relay should trip in 800 ms (T2P) with a target of
Z2P – ABC.
(b) Change RT = 4. Repeat the test. The relay
should trip in 1300 ms (OSTM + T2P) with a tar-
get of Z2P – ABC.