Littelfuse SE-330HV-20-01

The SE-330HV-20-01 serves as a vital monitoring relay for ground-fault and neutral-grounding-resistor applications. It continuously assesses the neutral-to-ground path ensuring that the neutral-grounding resistor (NGR) remains intact, which is essential for maintaining effective current-sensing ground-fault protection. An open NGR could lead to system malfunctions, giving a false impression of operational safety.

This model is compatible with both low- and medium-voltage transformers and generators, accommodating various grounding configurations across multiple industries, including manufacturing, chemical processing, and water treatment. For applications demanding compliance with the Australian standard AS/NZS 2081.3:2002, the SE-330AU variant is available. The SE-330HV is particularly suited for high-voltage requirements.

Technical specifications include an analog output current range of 4-20 mA, with relay contacts available in multiple forms: one Form A, one Form B, and two Form C. It operates on a supply voltage ranging from 28-52 VAC and 36-72 VDC. Communication is facilitated via USB, and the relay contact operating mode is configurable between fail-safe and non-fail-safe. The dimensions of the unit are 8.4 inches in height, 3.9 inches in width, and 5.8 inches in depth.