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PBO-3P-T: Three Phase Voltage Monitor


Voltage Range:

• 208 to 575VAC, 3Ø



SPDT Relay Contacts

5 Built-In Voltage Selections


• Over & Under Voltage

• Phase Loss

• Phase Imbalance

• Phase Reversal


The PBO-3P-T monitors 5 three phase voltages with the tolerances
pre-programmed into the PBO.

Each time the PBO is powered up, the processor evaluates the line voltage and compares it to the pre-programmed line voltages and tolerances. If the line voltage matches one of the programmed voltages and is within the tolerances, the output relay will be energized and the LED will be green. The PBO will indicate what voltage it is set for by flashing the LED green in a sequence corresponding to the selected voltage. If a voltage fault is detected, the LED will be red and if the phases are reversed, the LED will flash red.



Line Voltage:  208, 230, 380, 460 & 575VAC, 3Ø

Frequency: 45 to 65 Hz

Over/Under Voltage: ±15%

Phase Imbalance: Trip: 8%, Reset: 7%

Phase Rotation: A - B - C

Time Delays: 

Trip Time: 5 seconds (1 Second @ ±20%,                 Single Phasing 3Ø line)

Re-Start: 5 Seconds on power up

            30 Seconds after fault

Set-Up: Automatic on power up


    Good:     Continuous Green

    Fault Rotation:    Flashing Red (3Ø)

    Fault Voltage:     Solid Red

Power Consumption: 1VA

Output Rating @ 25°C:  

    10 Amps @ 120VAC

    6 Amps @ 277VAC

    1/8 HP @ 120/277VAC

    5 Amps @   20VDC


Mounting: Surface or DIN


    Line Side: 1/4” Push-On Tabs

    Control Side: 0.187” Push-On Tabs

Packaging: Epoxy Fill

Weight: 5 Ounces


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