Basic Current Protection Elements
The basic current operated protection elements in the PowerLogic ADVC Controller are:
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Phase Over current
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EF
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SEF
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NPS
All circuit breakers used with the PowerLogic ADVC Controller as an ACR are fitted with 2000:1 (or a 1000:1 for the PMSet E Series) CTs on each phase. The CT secondary currents are continually sampled by the controller to detect over current faults on the system.
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The Phase Over current element deals with the actual CT secondary values.
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The EF element deals with the vector sum of the phase currents.
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The SEF element deals with analogue measurement of the
spill current < 80 A primary and uses a low pass frequency filter to remove harmonic content. -
The NPS element deals with a value calculated in real time using the Fortescue formula for sequence components.
There is one global Trips to Lockout setting that applies to Phase Over current and EFs. SEF and NPS each have their own Trips to Lockout settings. They can also be set for between 1 and 4 trips but cannot exceed the global Trips to Lockout setting.
The global Trips to Lockout setting determines the maximum number of trips that can occur in a single sequence.
A sequence can end after less than the maximum number of trips if either the SEF or NPS Trips to Lockout settings is reached.