Seg WI Series User Manual

4.4.2
Inrush – Settings
DIP/HEX switches: ╚═▷ “11.1.6 Inrush – Settings via DIP Switches (WIC1‑2) or via HEX
Switches (WIC1‑3)”
4.4.2.1 Inrush – Settings via DiggiMEC or via Smart view
⚙
1. ▷
Activate the Inrush module »IH2«.
2. ▷
Specify the threshold for the ratio of the 2
nd
harmonic to the 1
st
harmonic:
• [Protection Para / IH2] »IH2 . IH2 / IH1« — as a percentage.•
3. ▷
Specify the maximum current, this is the upper limit for the Inrush module described
above:
• [Protection Para / IH2] »IH2 . Imax« — as a number value in units of the nominal•
current In.
4. ▷
If required for your application, de󰊟ne a maximum duration of the blocking signal.
(This is a phase-speci󰊟c timer.)
• [Protection Para / IH2] »IH2 . tmax« — in seconds.•
The typical duration of high inrush currents during empowering a transformer depends
on its rated power. These durations have roughly the following magnitude:
• For a rated power of 0.5 MVA, approx. 0.16 s,•
• for a rated power of 1 MVA, approx. 0.2 s,•
• for a rated power of 10 MVA, approx. 1.2 s,•
• for a rated power above 10 MVA, more than 1.2 s up to several minutes.•
(Durations cited from: Gerhard Ziegler, Digitaler Di󰊞erentialschutz: Grundlagen und Anwendungen, 2. Au󰊠.
2013).
5. ▷
Select the block mode:
• [Protection Para / IH2] »IH2 . 3-ph Blo« =•
Options:
◦ “Inactive” — phase-speci󰊟c mode: Each phase gets blocked, for which an◦
inrush current is detected.
◦ “Active” — overall mode: All phases get blocked as soon as an inrush current◦
is detected for at least one phase.
146 WIC1 WIC1-1.0-EN-MAN
4 Protective Elements
4.4.2 Inrush – Settings

Seg WI Series Specifications

General

Brand	Seg
Model	WI Series
Category	Relays
Language	English