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

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 monitoring 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 adjustable trip delays from 0.1 to 2.0 seconds. The unit supports selectable fail-safe or non-fail-safe operating modes, includes a standard reset button, and is conformally coated. It is CSA certified, UL Listed (E340889), and C-Tick compliant. The device has a dimensions of 150 mm H × 109 mm W × 100 mm D and requires a CT200 series current transformer and ER series sensing resistor for operation.