201A-AU - 201A-AU Series

Series: 201A-AU Questions? Contact Littelfuse Support
Littelfuse Voltage Monitoring Relays
The 201A-AU is a 3-phase, auto-ranging, dual-range voltage monitor that protects 190-480VAC, 50/60Hz motors regardless of size. Has user adjustable 1-30 second trip delay, manual or 1-500 second restart delay, and 2-8% voltage unbalance trip point. The product also provides a user selectable nominal voltage setpoint and the voltage monitor automatically selects between the 200V and 400V range. The Model 201A-AU includes advanced single LED diagnostics, where five different light patterns distinguish between faults and normal conditions.

This unique microcontroller-based voltage and phase-sensing device constantly monitors the 3-phase voltages to detect harmful power line conditions. When a harmful condition is detected, the 201A-AU's output relay is deactivated after a specified trip delay. The output relay reactivates after power line conditions return to acceptable levels.

Property (Mouseover for details) Value
Input Voltage (V) 190 to 480VAC
Maximum Input Power 5W
Input AC Line Frequency (Hz) 50/60Hz
Output Form Form C
Output Load Rating (VA) Pilot Duty: 480VA @ 240VAC B300; General Purpose: 10A @ 240VAC
Restart Delay Range Manual 1 - 500s adjustable
Trip Delay Range Under/Over and Unbalanced Voltage: 1 - 30s adjustable; Single-Phasing Faults: 1s fixed
Trip Point Accuracy (%) ±1%
Overvoltage Trip Voltage (%) 110%
Overvoltage Reset Voltage (%) 107%
Undervoltage Trip Voltage 90%
Undervoltage Reset Voltage (%) 93%
Voltage Unbalance Trip Point (%) 2-8% adjustable
Voltage Unbalance Reset (%) Trip setting minus 1% (5-8% or Trip setting minus 0.5% (2-4%)
Mounting Method DIN rail or surface mount (plug-in to OT08-PC socket)
Operating Temperature -40° to 70°C (-40° to 158°F)
Storage Temperature (F/C) -40° to 80°C (-40° to 176°F)
Humidity 10-95% non-condensing per IEC 68-2-3
Dimensions 1.75 in H x 2.38 in W x 4.13 in D (with socket) (44.5 x 60.3 x 104.8 mm)
Weight (lbs/g) 0.7 lb. (11.2 oz. 317.5 g)