5-182 C70 CAPACITOR BANK PROTECTION AND CONTROL SYSTEM – INSTRUCTION MANUALGROUPED ELEMENTS CHAPTER 5: SETTINGS5CUR UNBALCE 1 STG 1A PICKUP to CUR UNBALCE 1 STG 4C PICKUP — These settings specify pickup thresholds for stages 1through 4 in phases A through C in per-units (pu) of the nominal current of the differential source. A value of 1 pu is thenominal secondary current, or the nominal primary current, respectively, as configured under the differential source of thisfunction.CUR UNBALCE 1 STG 1 PKP DELAY to CUR UNBALCE 1 STG 4 PKP DELAY — This setting specifies the pickup time delay, individuallyper each stage of alarming/tripping. Each of the 12 comparators (four stages in three phases) uses an individual timer, butsettings for these timers are controlled individually per each stage, not per phase. The timers use a common drop out timedelay specified by the next setting.CUR UNBALCE 1 DPO DELAY — This setting controls a drop-out delay for the operate FlexLogic operands. Individual stagesapply individually configurable pickup delays, but use this common drop-out delay.CUR UNBL 1 BLK STG1 to CUR UNBL 1 BLK STG4 — These settings are used to block the function on a per-stage basis whenrequired. At minimum this function is blocked when the two banks are not paralleled. When unblocked, the functionbecomes operational after five cycles of intentional delay. High-set instantaneous protection on energization can beprovided by a separate instantaneous overcurrent function.Figure 5-91: Phase current unbalance logic5.7.4 Neutral current5.7.4.1 MenuSETTINGS GROUPED ELEMENTS SETTING GROUP 1(6) NEUTRAL CURRENT NEUTRAL CURRENT NEUTRAL TOC 1See below
