Neutral Current - GE C70 Instruction Manual

CHAPTER 5: SETTINGS
CUR UNBALCE 1 STG 1A PICKUP
through 4 in phases A through C in per-units (pu) of the nominal current of the differential source. A value of 1 pu is the
nominal secondary current, or the nominal primary current, respectively, as configured under the differential source of this
function.
CUR UNBALCE 1 STG 1 PKP DELAY
per each stage of alarming/tripping. Each of the 12 comparators (four stages in three phases) uses an individual timer, but
settings for these timers are controlled individually per each stage, not per phase. The timers use a common drop out time
delay specified by the next setting.
— This setting controls a drop-out delay for the operate FlexLogic operands. Individual stages
CUR UNBALCE 1 DPO DELAY
apply individually configurable pickup delays, but use this common drop-out delay.
to
CUR UNBL 1 BLK STG1 CUR UNBL 1 BLK STG4
required. At minimum this function is blocked when the two banks are not paralleled. When unblocked, the function
becomes operational after five cycles of intentional delay. High-set instantaneous protection on energization can be
provided by a separate instantaneous overcurrent function.

5.7.4 Neutral current

5.7.4.1 Menu
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  NEUTRAL CURRENT
 NEUTRAL CURRENT

C70 CAPACITOR BANK PROTECTION AND CONTROL SYSTEM – INSTRUCTION MANUAL
to
CUR UNBALCE 1 STG 4C PICKUP
to
CUR UNBALCE 1 STG 4 PKP DELAY
— These settings are used to block the function on a per-stage basis when
Figure 5-81: Phase current unbalance logic
 NEUTRAL TOC1



— These settings specify pickup thresholds for stages 1
— This setting specifies the pickup time delay, individually
See below
GROUPED ELEMENTS
5
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