Littelfuse, Inc. SE-330 Series – Neutral-Grounding-Resistor Monitor SE-330-23-01

The SE-330 is a neutral-grounding-resistor monitoring relay that detects open or shorted neutral-grounding resistors and ground faults as small as 100 mA using Discrete Fourier Transform filtering to prevent false trips from harmonic noise. It provides two programmable Form C and one programmable Form A output contacts, an analog 4-20 mA output, and a pulsing ground-fault location function. It includes an onboard 100-event recorder with date and time, and supports USB, DeviceNet, EtherNet (Dual RJ45), IEC 61850, and Modbus TCP communications. The relay has a panel or surface mount design, measures 213 mm in height, 98 mm in width, and 132 mm in depth, and features conformal coating for environmental protection. It is CSA certified, UL Listed (E340889), CE marked, and RCM compliant. The SE-330-23-01 variant operates on a 48 Vdc power supply and includes EtherNet (Dual RJ45) communication.