Littelfuse® Symcom 201A-AU Phase Monitoring Relay, 190 to 480 VAC, Form C

Voltage Sensing Relays & Monitors
493357 MFG #: 201A-AU
172.69000 / ea
The 201A-AU is a 3-phase, auto-ranging, dual-range voltage monitor that protects 190-480 VAC, 50/60 Hz motors regardless of size. Has user adjustable 1-30 sec trip delay, manual or 1-500 sec restart delay, and 2 to 8% voltage unbalance trip point. The product also provides a user selectable nominal voltage set point and the voltage monitor automatically selects between the 200 V and 400 V 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.
  • Features
12 to 22 AWG wire
Stranded/solid wire
-40 to 70 deg C operating temperature
12 in-lb torque
Constant monitoring of loss of any phase, low voltage, high voltage, voltage unbalance, phase reversal, rapid cycling, harmful power line conditions
Allows flexibility in panel installation
Automatically senses system voltage between 190 - 480VAC. saves setup time
Quick visual indicator for cause of trip and relay status
Allows compatibility with a variety of motors and reduces nuisance tripping
Prevent nuisance tripping due to rapidly fluctuating power line conditions