Siemens 7SR51 - Logic of the Function; Application and Setting Notes

Logic of the Function
[lo_7SR5_27logicdiagram, 1, en_US]
Figure 5-3
Logic Diagram: 27 Undervoltage Protection – 3 Phase
Application and Setting Notes
Parameter: 27 Common > Input Selection
•
Default setting: ph‑ph
This parameter defines whether the undervoltage protection function operates on phase‑neutral voltages
VA, VB, and VC or phase‑phase voltages VAB, VBC, and VCA and is applied to all elements of this function
type.
Parameter Value
Description
Ph‑Ph Where required to monitor the load under voltage conditions the phase
to phase value is appropriate.
Ph‑N This setting may be considered where single phase loads are connected.
5.2.3
5.2.4
Protection and Automation Functions
5.2 27 Undervoltage Protection – 3-Phase
Reyrolle 7SR5, Overcurrent Protection Device, Device Manual 151
C53000-G7040-C014-1, Edition 11.2019