Entec EVRC2A-N6-NT - 7.4. Sensitive Earth Fault (SEF)

RECLOSER CONTROL EVRC2A-N6,NT http://www.entecene.co.kr
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ENHANCED TECHNOLOGY
7.4. Sensitive Earth Fault (SEF)
The sensitive earth fault (SEF) is applicable to systems that have restricted current flow for phase
to earth fault. The SEF is not applicable to the case in 4 wire multi-earthed systems. The
sensitivity of SEF element for non-earthed systems is dependent upon available fault current and
the accuracy of CTs. For SEF element, EVRC2A has the separate SEF terminal on side panel.
This input can be connected in series with the provided phase CT’s (standard) or connected to a
separate window type ZCT.
The SEF element provides a definite time delay versus current. The SEF element is enabled in
the Primary, Alternate settings and both [PROTECTION ENABLED] and [SEF ENABLED]
in user interface panel.
For user systems, a directional SEF is available. The directional control is polarized by a zero
sequence voltage(V0). The VD or PTs should be connected Wye-grounded.
The SEF element in the following three settings should be enabled.
SEF Pickup Current Setup
PRIMARY SETTING / PROTECTION / PICKUP CURRENT / S.E.F
Range*
OFF, 4 ~ 160A (prior to Ver 6.15 of EVRC2A)
OFF, 1 ~ 160A (from Ver 6.15 of EVRC2A)
Default
OFF
Step
1A
Set the pickup current of SEF element.
NOTE :
The user shall request a CT that satisfies the relevant
accuracy when setting below 2A so that the SEF element
operates properly.
NOTE :
For the products that are dispatched with ZCT installed, the
setting range of this item is “OFF, 0.1~16.0 (0.1A Step)”. It
is possible to check whether the product is dispatched with
ZCT installed by checking
“MAIN MENU/ STATUS/
CONTROL TYPE”
menu. Refer to
“9.4. Control Type”
.
[PICKUP CURRENT(A)]
>Phase: 500
>Ground: 250
>S.E.F: OFF