Issue:
Circuit breaker trips faster than minimum trip band for instantaneous protection when performing automatic trip curve test on short-time or instantaneous segments of time-current curve and/or HARDWARE appears in status cell on Automatic Trip Curve Test screen.
Product Line:
Circuit breakers
Resolution:
The short answer is: Make sure breaker is closed, turn down the instantaneous and/or short time setting, and retest.
The test kit is most likely injecting a current higher than the instantaneous override value, which makes it trip on instantaneous override rather than instantaneous.
The long answer is:
Make sure circuit breaker is always in closed position before beginning secondary injection of each fault. This will eliminate tripping due to close and latch protection.
Does long time segment of time current curve pass when performing automatic trip curve test?
A. YES
For communicating Micrologic trip units, if AP trip indicator LED on trip unit comes on when testing short time or instantaneous segments of time current curve, then circuit breaker has tripped on instantaneous override, close and latch, or selectivity protection functions. For non-communicating Micrologic trip units, no trip indicator LED is available. Check that peak value for signal being injected does not exceed instantaneous override or selectivity protection levels. See published time current curves.
B. NO
Contact the customer care center to have the FFTK returned for repair (repairing FFTKs is no longer available).
For a complete list of error codes please see document 48049-183-06
Circuit breaker trips faster than minimum trip band for instantaneous protection when performing automatic trip curve test on short-time or instantaneous segments of time-current curve and/or HARDWARE appears in status cell on Automatic Trip Curve Test screen.
Product Line:
Circuit breakers
Resolution:
The short answer is: Make sure breaker is closed, turn down the instantaneous and/or short time setting, and retest.
The test kit is most likely injecting a current higher than the instantaneous override value, which makes it trip on instantaneous override rather than instantaneous.
The long answer is:
Make sure circuit breaker is always in closed position before beginning secondary injection of each fault. This will eliminate tripping due to close and latch protection.
Does long time segment of time current curve pass when performing automatic trip curve test?
A. YES
For communicating Micrologic trip units, if AP trip indicator LED on trip unit comes on when testing short time or instantaneous segments of time current curve, then circuit breaker has tripped on instantaneous override, close and latch, or selectivity protection functions. For non-communicating Micrologic trip units, no trip indicator LED is available. Check that peak value for signal being injected does not exceed instantaneous override or selectivity protection levels. See published time current curves.
B. NO
Contact the customer care center to have the FFTK returned for repair (repairing FFTKs is no longer available).
For a complete list of error codes please see document 48049-183-06
Released for:Schneider Electric Canada
