355 Series - 3-Phase Voltage/Phase Monitor

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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 355-200 is equipped with a heavy-duty 10A general purpose SPDT relay. The 355-400 and 355-600 are equipped with a 470VA @ 600VAC pilot duty SPDT relay. A high voltage (600V) DPDT relay output option is available with the 400V model.

Access specifications, certifications, check availability and order parts below

Catalog #Input
Voltage (V)
Output
Form
Termination TypeMounting MethodDimensionsWeight (lbs/g)Input AC Line Frequency (Hz)Maximum Input PowerOutput Load Rating (VA)Overvoltage Reset Voltage (%)Overvoltage Trip Voltage (%)Repeat Accuracy (%)Restart Delay RangeStorage Temperature (F/C)Trip Delay RangeStockCompare
355200190 - 240 VacSPDTTorque: 7 in-lbs; Wire Size: 12 - 18 AWG#8 screws2.93 H x 5.27 W x 2.95 D in. (74.4 x 133.9 x 74.9 mm)0 Kg50 / 60 (50 will increase all delay timers by 20%)6Pilot Duty: 480 VA @ 240 Vac; General Purpose: 10 A or 1 hp @ 240 Vac107%110%±0.1%After a Fault or power loss: Manual; 2 - 300 s adjustable-40° to 80°C (-40° to 176°F)Under/Over and Unbalance Voltage: 2 - 30 s adjustable; single-Phase faults (>25%UB): 2 sCheck
355400380 - 480 VacSPDTTorque: 7 in-lbs; Wire Size: 12 - 18 AWG#8 screws2.93 H x 5.27 W x 2.95 D in. (74.4 x 133.9 x 74.9 mm)0 Kg50 / 60 (50 will increase all delay timers by 20%)6Pilot Duty: 470 VA @ 600 Vac; General Purpose: 10 A107%110%±0.1%After a Fault or power loss: Manual; 2 - 300 s adjustable-40° to 80°C (-40° to 176°F)Under/Over and Unbalance Voltage: 2 - 30 s adjustable; single-Phase faults (>25%UB): 2 sCheck
3554005380 - 480 VacDPDTTorque: 7 in-lbs; Wire Size: 12 - 18 AWG#8 screws2.93 H x 5.27 W x 2.95 D in. (74.4 x 133.9 x 74.9 mm)0 Kg50 / 60 (50 will increase all delay timers by 20%)6Pilot Duty: 470 VA @ 600 Vac; General Purpose: 10 A107%110%±0.1%After a Fault or power loss: Manual; 2 - 300 s adjustable-40° to 80°C (-40° to 176°F)Under/Over and Unbalance Voltage: 2 - 30 s adjustable; single-Phase faults (>25%UB): 2 sCheck
355600475 - 600 VacSPDTTorque: 7 in-lbs; Wire Size: 12 - 18 AWG#8 screws2.93 H x 5.27 W x 2.95 D in. (74.4 x 133.9 x 74.9 mm)0 Kg50 / 60 (50 will increase all delay timers by 20%)6Pilot Duty: 470 VA @ 600 Vac; General Purpose: 10 A107%110%±0.1%After a Fault or power loss: Manual; 2 - 300 s adjustable-40° to 80°C (-40° to 176°F)Under/Over and Unbalance Voltage: 2 - 30 s adjustable; single-Phase faults (>25%UB): 2 sCheck
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