Littelfuse 201A-AU Monitor

3-PHASE PLUG-IN VOLT MON/ 190-

Littelfuse 201A-AU 3-Phase Plug-In Voltage Monitor – Reliable Motor Protection

Protect your three-phase motors with the Littelfuse 201A-AU Voltage Monitor, a versatile OEM-quality solution designed for 190–480 V AC, 50/60 Hz systems. This auto-ranging, dual-range voltage monitor ensures continuous protection for motors of any size by detecting harmful power line conditions such as voltage unbalance, phase loss, over-voltage, under-voltage, or phase reversal.

Key Features

• Proprietary microcontroller-based circuitry for precise monitoring

• Auto-sensing wide voltage range (190–480 V AC)

• Advanced LED diagnostics with color-coded patterns for easy fault identification

• Compact design for 8-pin plug-in, DIN-rail, or surface mounting

• Adjustable voltage unbalance trip setting (2–8%)

• Adjustable trip delay (1–30 seconds) and restart delay (manual or 1–500 seconds)

Benefits

• Constantly monitors three-phase voltages to detect harmful power line conditions

• Protects motors from phase loss, low/high voltage, voltage unbalance, and phase reversal

• Automatically selects between 200 V and 400 V range, reducing setup time

• Quick visual indicator minimizes troubleshooting time with LED diagnostics

• Flexible installation options for panels of any size

• Prevents nuisance tripping caused by rapid voltage fluctuations

• Compatible with a wide range of motors, improving system reliability

The Littelfuse 201A-AU provides advanced protection and easy installation, making it an ideal choice for industrial and commercial motor control applications. Keep your motors safe and your operations running smoothly with this intelligent, auto-ranging voltage monitor.