TERASAKI AME Series, Instruction Manual

Page: 28 / 40

KRB-5200h
-22-
③
Close the ACB.
④
Check for the long time-delay trip pick-up current (I
1
).
To do this, increase the test current gradually and measure the current at which the I
1
pick-up
LED begins to flicker.
It is acceptable when the measured current falls within the range of 92.5 to 107.5% of I
1
(or
92.5 to 117.5% of I
1
when I
1
is 50% or less of I
CT
).
After testing, decrease the test current. Otherwise, the ACB will trip open.
⑤
Check the time delay setting (T
1
).
Caution : An error of 1% in test current will lead to an error of 4% in time delay. Apply the
accurate test current to the OCR.
To check the time delay setting, apply a test current of I
1
x 1.2 and, using a stopwatch, measure
the time from current application to ACB tripping. Note that a gradual increase of the test
current could cause erroneous results.
It is acceptable when the measured time falls within the range of 85 to 115% of T1 (or 80 to
120% of T
1
when I
1
is 50% or less of I
CT
).
⑥
Repeat steps
④
and
⑤
for remaining phases.
⑦
After completion of the tests, return the ACB to the original state.

If the tests show any problem, contact our branch office or your local agency.
I
１
Pick-up LED