9137200997 Rev D
BE1-51 Tests and Adjustments
5-11
Step 1.
Verify that the test setup is as described in
TAP and TAP (NEUTRAL) Selector Setting,
Steps 1
through 6.
Step 2.
Connect the test setup to the instantaneous 1 element output terminals (2 and 10) as shown in
Figures 5-1 through 5-4. The timer should not be connected.
Step 3. Set the front panel
INST 1
control to a position approximating the desired instantaneous 1
overcurrent pickup point for the relay.
Step 4.
Apply current to the relay.
Step 5. Rapidly increase the overcurrent input to the relay until the instantaneous output relay just
energizes. Note the overcurrent threshold reading on the ammeter.
Step 6.
Remove input current.
Step 7.
Reset the
INST TARGET
(if present).
Step 8. If the overcurrent threshold reading from Step 5 was too high or low, adjust the front panel
INST 1
control CCW to lower (or CW to raise) the instantaneous 1 overcurrent pickup point.
Repeat Steps 4 through 8. If the overcurrent threshold reading from Step 5 was
NOT
too high
or low, proceed to Step 9.
Step 9.
Reconnect the output to the neutral current sense terminals. See Figures 5-3 or 5-4.
Step 10. Set the front panel
INST 1 (NEUTRAL)
control to a position approximating the desired neutral
instantaneous 1 overcurrent pickup point for the relay.
Step 11. Apply current to the relay.
Step 12. Rapidly increase the overcurrent input to the relay until the instantaneous output relay just
energizes. Note the test set overcurrent threshold reading on the ammeter.
Step 13. Remove the input current.
Step 14. Reset the
INST TARGET
(if present).
Step 15. If the overcurrent threshold reading from Step 13 was too high or low, adjust the front panel
INST 1 (NEUTRAL)
control CCW to lower (or CW to raise) the Neutral Instantaneous 1
Overcurrent Pickup Point. Repeat Steps 9 through 14. If
NOT
, proceed to the next test.
INST 2 Control Setting
For this adjustment, repeat
INST 1 Control Setting,
but substitute instantaneous 2 output terminals (11
and 12) and the front panel
INST 2
controls. Because neutral sensing does not apply to this pickup point,
ignore Steps 9 through 15.
CAUTION
Steps 3 through 8 provide the application of overcurrent for short periods to allow
adjustment while avoiding overheating of the input sensing transformers. To
avoid damaging the relay, do not attempt to apply a constant high level of input
current for adjustment of the front panel
INST 1
,
INST 1 (NEUTRAL)
, or
INST 2
controls.
NOTE
For relays with two-phase-and-neutral or three-phase-and-neutral sensing
(Sensing Input Types I or X), perform Steps 9 through 14.