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The 355 is a 3-phase voltage monitor with adjustable trip and restart delay, adjustable voltage unbalance and multiple diagnostic lights. It is perfect for heavy-duty applications that need both protection and simple user-friendly diagnostics. Applications include pump panels, commercial HVAC, oil rigs and others.
The 355 uses microcontroller technology to monitor incoming voltage and de-energize its output relay if power problems exist. The 355 can protect motors from damage caused by single-phasing, high and low voltage, phase reversal and voltage unbalance. It has four diagnostic LEDs that clearly show overvoltage, undervoltage, voltage unbalance, reverse-phase and normal conditions.
The 355-400 is equipped with a 470VA @ 600VAC pilot duty SPDT relay.

  • Input Voltage (V): 380 to 480VAC
  • Maximum Input Power: 6W
  • Input AC Line Frequency (Hz): 50/60Hz (50Hz will increase all delay timers by 20%.)
  • Output Form: SPDT
  • Output Load Rating (VA): Pilot Duty: 470VA @ 600VAC; General Purpose: 10A
  • Restart Delay Range: After a Fault or power loss: Manual 2 - 300s adjustable
  • Repeat Accuracy (%): ±0.1%
  • Trip Delay Range: Under/Over Voltage and Unbalance: 2 - 30s adjustable; Single-phasing Faults (>25%UB): 2s
  • 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%
  • Termination Type: Torque: 7in-lbs; Wire Size: 12-18AWG
  • Mounting Method: #8 screws
  • Operating Temperature: -40° to 70°C (-40° to 158°F)
  • Storage Temperature (F/C): -40° to 80°C (-40° to 176°F)
  • Dimensions: 2.93 in H x 5.27 in W x 2.95 in D (74.4 x 133.9 x 74.9 mm)
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Product Type:

Voltage Meter






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