Littelfuse, Inc. SE-325 Series – Neutral-Grounding-Resistor Monitor SE-325T

The SE-325 series is a neutral-grounding-resistor monitor designed for resistance-grounded systems up to 25 kV to detect ground faults and NGR failures by measuring current and voltage in the neutral-to-ground path. It features a Form A output contact, adjustable ground-fault trip levels from 0.5 to 4.0 A, and selectable trip delays from 0.1 to 2.0 seconds. The unit supports selectable fail-safe or non-fail-safe operating modes, is conformally coated, and mounts with dimensions of 150 mm height, 109 mm width, and 100 mm depth. It is CSA certified, UL Listed (E340889), and C-Tick compliant. The SE-325 requires a CT200 series current transformer and ER series sensing resistor for interface. Control power options include 120 Vac, 120 Vac/Vdc, and 240 Vac.