ABB REL 551 2.3 Series Installation And Comissioning Manual page 131



Two step time delayed phase overcurrent
protection (TOC2)
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Check with the current I>Low or 2·I>Inv (the highest value of
these two) and the current that according to the inverse time curve
corresponds to tMin.
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Continue to test another function or complete the test by setting the test mode to off.
Restore connections and settings to the original values, if they were changed for testing
purpose.
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