Cease to energize is a DER state in which the unit delivers no active power at its point of connection, whether conditions are steady or transient. During this state the DER may still import power and exchange reactive power, but only to keep its housekeeping and auxiliary loads supplied, and any reactive exchange must come solely from passive devices. The requirement can also be met by disconnecting the Local EPS, or the part of it that holds the DER, from the Area EPS, and the DER may keep supplying that isolated part. Momentary cessation is a related ride-through behavior: for Category III DER, when voltage falls into the momentary cessation region, the DER ceases to energize without tripping and then restores its output. Setting Permit service to disabled directs a DER to cease to energize and trip, and an energy storage system that has ceased to energize may keep charging. In the field, the function is verified by operating a load interrupting device, confirming that the output terminals are de-energized and do not reconnect before the required delay, and repeating this on each phase.
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related_toc1 drafted · lead IEEE 1547-2018 4.5 Cease to energize performance requirement proposed
Scope: standard IEEE 1547-2018 proposed
In the cease to energize state, the DER shall not deliver active power during steady-state or transient conditions.
sec=4.5 h=0558bd01f897tbl=4.r16 h=23d824c79f06c2 drafted · lead IEEE 1547-2018 proposed
Defines the cease to energize state and the optional momentary cessation parameters.
sec=4.5 h=0558bd01f897sec=h198 h=83456634f8d4tbl=43.r2 h=79cd25c57bc0sec=10.6.11 h=ded63491f0a8sec=h108 h=a44acf481535c3 verified · fact Permit service / cease to energize
Scope: standard IEEE 1547-2018 proposed
Setting Permit service to disabled directs the DER to cease to energize and trip.
sec=10.6.11 h=ded63491f0a8verified by: review-workflowverified on: 2026-10-24
c4 verified · fact Voltage ride-through
Scope: standard IEEE 1547-2018 proposed
For Category III DER, voltage inside the momentary cessation region requires ceasing to energize without tripping, then restoring output.
sec=h108 h=a44acf481535tbl=43.r2 h=79cd25c57bc0verified by: review-workflowverified on: 2026-10-24
c5 verified · fact IEEE 1547 performance categories
Momentary cessation behavior is specified for Category III DER.
sec=h108 h=a44acf481535verified by: review-workflowverified on: 2026-10-24
c6 drafted · lead Area electric power system
Cease to energize may alternatively be met by disconnecting the Local EPS from the Area EPS; the Area EPS operator may request the remaining reactive susceptance.
sec=4.5 h=0558bd01f897sec=4.5 h=03d015c97643c7 verified · fact Local electric power system proposed
Reactive exchange limits depend on aggregate DER rating of the Local EPS; the DER may keep supplying a disconnected portion of the Local EPS.
sec=4.5 h=0558bd01f897sec=4.5 h=03d015c97643verified by: review-workflowverified on: 2026-10-24
c8 drafted · lead Cease to energize functionality test proposed
Scope: standard IEEE 1547-2003 proposed
Operate a load interrupting device, verify output terminals de-energize and do not reconnect for the required delay; test each phase individually.
sec=5.4.2 h=1992054d53f1tbl=6 h=1992054d53f1review note: support check: partial - The test content matches, but the passages do not show it belongs to IEEE 1547-2003; the references (4.1.4, 4.2.x, 4.4.1) are not tied to the edition in the passages.
c9 drafted · lead Battery energy storage system
An energy storage system that ceases to energize may continue charging; some battery systems report a cease-to-energize status flag over Modbus.
sec=h33 h=a83696c99ca7tbl=119.r23 h=1332337963c2related_to c7related_to c1related_to c7related_to c5