Littelfuse 201575-AU, 201A-AU Series, 3-Phase Voltage/Phase Monitor, Voltage Asymmetry, Voltage Sensing AC 475 ~ 600VAC, DIN-rail or surface mountable
Pickup available at 220 Alden Road
Usually ready in 24 hours
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The 201A-AU series is a three-phase, auto-ranging, dual-range voltage monitor that protects 190–480 V ac, 50/60 Hz motors regardless of their size. This monitor provides a user-selectable nominal voltage setpoint and will automatically select between the 200 V and 400 V range. Additional adjustment knobs allow the user to set a 1–30 second trip delay, a manual restart or 1–500 second restart delay, and a 2–8% voltage unbalance trip point. It includes advanced, single LED diagnostics where color and light patterns distinguish between faults and normal conditions. This unique microcontrollerbased voltage and phase-sensing unit constantly monitors the three-phase voltages to detect harmful power line conditions. When a harmful condition is detected, the output relay is deactivated after a specified trip delay. The output relay reactivates after power line conditions return to acceptable levels for a specified restart delay time (or manual reset).
Frequency | 50/60Hz |
Functional Characteristics | |
Low Voltage (% of setpoint) |
Trip 90%±1% Reset 93%±1% |
High Voltage (% of setpoint) |
Trip 110% ±1% Reset 107% ±1% |
Voltage Unbalance (NEMA) |
Trip 2–8% adjustable Reset Trip setting minus 1% (5–8%) Trip setting minus 0.5% (2–4%) |
Trip Delay Time | High, Low and Unbalanced Voltage: 1–30 seconds adjustable |
Single-Phasing Faults | 1 second fixed |
Restart Delay Time |
After a Fault: Manual, 1–500 seconds adjustable After a Complete Power Loss: Manual, 1–500 seconds adjustable |
Output Contact Rating (1-Form C) |
Pilot Duty 480 VA @ 240 V ac General Purpose 10 A @ 240 V ac |
General Characteristics | |
Ambient Temperature Range |
Operating -40° to 70 °C (-40° to 158 °F) Storage -40° to 80 °C (-40° to 176 °F) |
Trip & Reset Accuracy | ±1% |
Maximum Input Power | 5 W |
Relative Humidity | 10–95%, non-condensing per IEC 68-2-3 |
Terminal Torque | 12 in.-lbs. (for OT08-PC socket) |
Wire Size | 12–22 AWG solid or stranded |
Transient Protection (Internal) | 2500 V for 10 ms |
Standards Passed |
Electrostatic Discharge (ESD) IEC 61000-4-2, Level 3, 6 kV contact, 8 kV air |
Dimensions |
H 44.5 mm (1.75”) W 60.3 mm (2.38'') D 104.8 mm (4.13”) |
Enclosure | Polycarbonate |
Weight | 0.7 lb. (11.2 oz., 317.51 g) |
Mounting Method | DIN-rail or surface mount (plug in to OT08PC socket) |
Socket Available | OT08PC (UL Rating 600 V) |
Certification & Compliance |
UL UL508 (File #E68520) |