EMR-5000
IM02602012E
Commissioning: Current Unbalance Module
Object to be tested:
Test of the unbalanced load protection function.
Necessary means:
Three-phase current source with adjustable current unbalance; and
Timer.
Procedure:
Check the phase sequence:
Ensure that the
phase sequence is the same as that set in the field parameters.
Feed-in a three-phase nominal current.
Change to the »Measuring Values« menu.
Check the measuring value for the unbalanced current
»I2 Fund.«.
The measuring value displayed for
»
I2 Fund.«
should be zero (within the physical measuring accuracy).
If the displayed magnitude for I2 Fund. is the same as that for the balanced
nominal currents fed to the relay, it implies that the phase sequence of the
currents seen by the relay is reversed.
Now turn-off phase A.
Again check the measuring value of the unbalanced current
»
I2 Fund.« in the »Measuring Values« menu.
The measuring value of the unbalanced current
»
I2 Fund.« should now be 33%.
Turn-on phase A, but turn-off phase B.
Once again check the measuring value of the unbalanced current I2 Fund. in the »Measuring Values« menu. The
measuring value of the asymmetrical current
»
I2 Fund.« should be again 33%.
Turn-on phase B, but turn-off phase C.
Again check the measuring value of unbalanced current
»
I2 Fund.« in the »Measuring Values« menu. The
measuring value of the unbalanced current
»
I2 Fund.« should still be 33%.
Testing the trip delay:
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