Littelfuse, Inc. SE-330 Series – Neutral-Grounding-Resistor Monitor SE-330-08-00

The SE-330 is a neutral-grounding-resistor monitoring relay that continuously verifies the integrity of the neutral-grounding resistor by measuring neutral current, voltage, and resistance. It detects open or shorted resistors and ground faults as small as 100 mA using DFT filtration to prevent false trips from harmonic noise. The relay includes two programmable Form C and one programmable Form A output contacts, an analog 4-20 mA output, and an on-board microSD card for data logging. It features a Mini USB port for local communication and supports IEC 61850 with dual SC Fiber and RJ45 interfaces. The device is conformally coated for environmental protection, mounted on a panel or surface, and carries CSA, UL, CE, and RCM certifications. It operates with a 24 Vdc power supply as specified in the ordering code for this variant.