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PBO-MRTU: Modbus Single & Three Phase Voltage Monitor

RK_digikey image_PBOMRTU.png

Voltage Ranges:

• 115 to 277VAC, 1Ø

• 200 to 600VAC, 3Ø



21 Built-In Voltage Selections

All Settings are Read/Write


Data is Communicated via ModbusRTU


Power and Communications Status LED


The PBO-MRTU monitors 21 single and three phase voltages and tolerances pre-programmed into the PBO and communicates all of the voltages, set-points and faults via ModbusRTU. All voltages and setting address are available as read/write. There is no output relay in the PBO-MRTU.


The Modbus addresses are downloadable at

The LED operations are as follows:

Continuous green LED – The PBO-MRTU has power

Green Flashing LED – The PBO is detecting communications on the Modbus network

Red Flashing LED – The PBO-MRTU is transmitting data on the Modbus network



Line Voltage: 115 to 277VAC, 1Ø
   200 to 600VAC, 3Ø

Supply Voltage: 12 to 24 VAC/VDC

Frequency: 45 to 65 Hz

Over/Under Voltage: 3% to 15%

Phase Imbalance: 3% to 15%

Phase Rotation: A - B - C

Time Delays: 

    Trip Time: 1 Sec. to 10 Sec. @ ±20%

    Re-Start: 1 Sec. to 5 Min. & Manual Reset


    Power: Continuous Green

    Transmitting Data: Flashing Red 

    Communications on Network: Flashing Green

Power Consumption: 1VA


Mounting: Surface or DIN

Termination: Pluggable Terminal Block

Packaging: Epoxy Fill

Weight: 5 Ounces


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