9252000991 Rev N
BE1-50/51B Testing
5-7
Integrating Reset Test (Applicable Only to 200 Series Relays)
Perform preliminary setup:
•
Connect test setup as shown in Figure 5-1.
•
Ensure that SW3 switches are set correctly: SW3-1 for operating frequency, SW3-2 to OFF (no
instantaneous delay), SW3-3 to OFF (no instantaneous delay (100 series relays) or ABB type
curves selected (200 series relays)), and SW3-4 to ON (selects integrating reset).
•
Set TIME DIAL to 4.5.
•
Set CURVE to I.
•
Set TIME PICKUP to 0.2.
•
Set INST PICKUP to 18.0.
Step 1. Set target current source to 1.0 ampere, ac.
Step 2. Read all of Step 3 before beginning Step 3.
Step 3. Apply 0.8 ampere input current to terminals 8 and 9. After the unit trips, remove the input current
for 20 ±0.25 seconds, then reapply the 0.8 ampere input current. Record the elapsed time from
the re-application of input current to the output retrip.
Result:
Elapsed time should be 1.55 ±0.3 seconds.
SETTING THE RELAY
Select the desired relay settings before putting the relay into service. Changing pickup current settings
while the relay is in service may cause tripping.
PERIODIC TESTS
General
All relays should be tested periodically to identify and correct any problems that are found.
Single phase relays such as the BE1-50/51B are normally used in groups of four (three phase and
ground) on the protected circuit. This relay scheme allows each unit to be withdrawn one at a time for
testing purposes without losing protection. Only three are required at any one time to sense all types of
faults on a grounded wye system. Refer to Figures 5-1 and 5-2 for recommended test setups.
Periodic Test
Periodic testing should consist of the following procedures.
Step 1. Verify that the instantaneous pickup is within ±2% of the value set on the dials. Pickup occurs
when the INST output contacts close.
Step 2. Verify that the time pickup is within ±2% of the value set on the dials. Pickup occurs when the
LED turns GREEN then RED.
Step 3. Verify that the time to trip for the curve and time dial settings at a multiple of six is the same as
the time given on the characteristic curve. Refer to Appendix A for the characteristics curves.
Step 4. Verify that the time to trip for the instantaneous element at a pickup multiple of 2 is not greater
than the time given on the instantaneous characteristic curve. Refer to Section 1 for the
instantaneous characteristic curve.
Step 5. Verify that the 51 AUX contacts close when the time overcurrent element trips.
Step 6. Verify that the targets operate with one ac ampere of trip current in the trip circuits and that they
can be reset using the RESET BUTTON.
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