LEM SATURN 100 plus Manuel D'utilisation page 28

Measuring
Phase 2
This phase serves to check the FI-circuit breaker for early tripping. For this purpose,
0.35 of the nominal fault current is applied for 500 ms.
If the circuit breaker trips during this test, it is either too sensitive or biased by
comparatively high fault currents in the system.
If this test is concluded with positive results and the measured contact voltage in
phase 1 was less than 50 V, phase 3 will be performed.
Phase 3
To conclude circuit-breaker testing with tripping, the full nominal fault current is now
applied. Tripping is checked with the set test current (1xI ∆N ,2xI ∆N , 5xI ∆N or the
increasing test current), and the tripping time „t A " as well as the tripping current „I A "
(when the option „increasing test current" is selected) are measured.
If the circuit breaker fails to trip within 500 ms, the current is automatically
interrupted for safety reasons, and the failure of the FI-Circuit breaker to trip is
displayed.
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