SE-325SNT - SE-325 Series

Series: SE-325
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The SE-325 Neutral-Grounding-Resistor Monitor is used on resistance-grounded systems up to 25 kV to monitor the integrity of the neutral-to-ground path and to detect ground faults. It measures current and voltage in a transformer or generator neutral-to-ground connection and continuity of the neutral-grounding resistor (NGR). The SE-325 coordinates these three measurements to detect a loose connection, corrosion, ground fault, or NGR failure, and provides one alarm or trip output contact.

Property (Mouseover for details) Value
Approvals CSA
Relay Contacts One Form A (N.O.)
Supply Voltage (VAC) 120
IEEE Device Numbers 50G
Relay Contact Operating Mode Fail-safe
Non Fail-safe

pdf icon SE-325 Datasheet

pdf icon SE-325 Manual

A high-resistance-grounded system uses a neutralgrounding resistor (NGR) with a low let-through current to limit ground-fault current. This is an improvement over low-resistance- or solidly grounded systems because, in those systems, a ground-fault flash hazard exists and a ground fault can result in substantial point-of-fault damage.

pdf icon SE-325 Manual Russian

pdf icon SE-325 Cross Reference Russian

pdf icon SE-325 Manual Chinese

dwg SE-325 CAD Drawing

dwg ER-600VC CAD Drawing

dwg ER-25kv CAD Drawing

dwg Littelfuse Protection Relays RK-302 CAD Drawing

dwg Littelfuse Protection Relays RK-325 CAD Drawing

pdf icon TN GF-10 Pulsing Ground-Fault Systems

pdf icon TN RG-01 NGR Monitoring Isolated Ground Beds

pdf icon TN RG-02 SE-325 on Alarm Only Systems

pdf icon TN RG-03 SE-325 Settings

pdf icon TN RG-04 SE-325 Guideform Specification

pdf icon TN RG-06 SE-VS1002K Voltage Scaler

pdf icon TN RG-07 SE-VS50010K Voltage Scaler

pdf icon TN RG-09 Single NGR for Multiple Sources

pdf icon TN-RG11 Voltage Metering on RG Systems

pdf icon TN RG-12 Convert Ungrounded to Resistance Grounded

pdf icon TN RG-14 NGR Package Checklist

pdf icon TN RG-15 Implementing Resistance Grounding on Solidly Grounded Systems

SE-325 STP 3D Model

pdf icon TN 11-1 Ground-Fault CT Selection Guide

11-1AU Earth-Fault CT Selection Flowchart Australia


pdf icon 11-2 Locating Phase Conductors in a Zero-Sequence-CT Window

An ideal window-type current transformer responds only to the sum of the currents flowing through its window...

pdf icon 11-4 Trailing Cable Types

pdf icon 11-5 Polycast 200 5 CT Test


pdf icon 11-7 Locating Phase Conductors in a Zero-Sequence CT Window