Littelfuse SE-330AU-08-01 NGR Monitor, Dual SC Fiber, IEC 61850, NC

The Littelfuse SE-330AU-08-01 is a Neutral Grounding Resistor Monitor (NGR monitor) designed for continuous supervision of neutral-earthing resistors in resistance-grounded AC systems. With wide supply inputs (65–265 VAC / 85–275 VDC), IEC 61850 and USB communications, and adjustable trip level/time settings, it provides reliable earth-fault detection for low- and medium-voltage transformers, generator neutrals and distribution protection applications that require proven NER integrity verification.

Key Features

• Continuous monitoring of neutral current, neutral-to-earth voltage and neutral-to-earth resistance.
• Detects open or failed neutral-earthing resistor (NER) to prevent loss of earth-fault protection.
• Wide supply voltage support: 65–265 VAC and 85–275 VDC for flexible installation.
• Communication options include IEC 61850 and USB for integration and setup.
• Front-panel switch and remote N.O. contact reset plus fail-safe operation for secure response.
• Standard conformal coating and harmonic filtering plus adjustable trip level and time settings.

Technical Specifications

Applications

Use for NGR monitoring on low- and medium-voltage transformers, generator neutral supervision, distribution substations, industrial power systems and critical plant feeders where earth-fault detection and NER integrity are required.

We supply genuine Littelfuse protection relays through authorized distribution channels from our Batam base, with fast delivery across Indonesia and Southeast Asia. Competitive lead times and local support—contact us to request a quotation or technical assistance for SE-330AU-08-01 installations.