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corribo
Apr 5, 2009, 04:42 PM
Masterpact M16H1 ACB, with STR38S Trip Unit. In=1600A.
I'm aware that the trip unit may not function correctly while detecting currents below 20% of rated current. But my specific question is, could these conditions while causing the STR38S Trip Unit to malfunction, actually cause the unit to trip. As an example, chosen settings Io x In x Ir = approx. 1414A. With average amps per phase at approx. 80A, it is accepted that the Trip Unit may not follow the current/time curve settings. But could these conditions contribute to the unit tripping?

sathe1963
Apr 18, 2009, 09:23 AM
Malfunctioning of processor. Local heating if any to be detected... recommended before replacing.

tigert
Jul 12, 2009, 06:46 PM
Should be refreshed the unit. The new version soft can solved the Malfunction.