Basler BE1-50/51B-217, Инструкция по эксплуатации

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BE1-50/51B-217 Testing
5-6
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-217 are normally used in groups of four (three phase and
ground) on the protected circuit. Only three are required at any one time to provide complete protection.
The fourth one assures that protection is maintained even if one relay failed.
This protection scheme also allows one unit at a time to be withdrawn for testing purposes without
loosing protection during the test. 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 ON.
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 Section 1 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 LEVER.
This completes the periodic test.