PBO-T: Single & Three Phase Voltage Monitor


Voltage Ranges:

• 115 to 265VAC, 1Ø

• 208 to 575VAC, 3Ø



SPDT Relay Contacts

22 Built-In Voltage Selections


• Over & Under Voltage

• Phase Loss

• 115 to 265VAC, 1Ø

• 208 to 575VAC, 3Ø


If the voltages and rotation (3Ø) are within the pre-established parameters, the PBO will illuminate the LED green on a continuous basis and energize the internal relay, transferring the output contacts. If the voltages and/or rotation (3Ø) are outside any of the pre-established parameters, the PBO internal relay will not energize or de-energize if already energized. The LED will be solid red for a voltage fault or flashing red if there is a phase reversal (3Ø).


To select the line voltage, remove the jumper before powering up the equipment. With the jumper removed the line voltages present at the time of power up will be compared to the 9 voltages available in the PBO. If the line voltage matches one of the line voltages designed into the PBO and all of the pre-programmed tolerances, the output relay will energize after the evaluation period.


To determine what voltage range the PBO is set for while in operation, remove the jumper. The LED will indicate the voltage range by flashing red or green in a sequence corresponding to the selected voltage.



Line Voltages

Monitored: 115, 208, 230 & 265VAC, 1Ø, 50/60Hz

        208, 230, 380, 460 & 575VAC, 3Ø, 50/60Hz

Frequency Range (45 to 65Hz)

Faults:  Overvoltage (+15%)

         Undervoltage (-15%)

         Phase Loss (-20%)

         Phase Rotation

         Phase Imbalance: Trip: (8%); Reset: (7%)

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, based on jumper


Good: Continuous Green


       Rotation:Flashing Red (3Ø)

       Voltage: Solid Red


Packaging: Surface mounting with ¼” & 0.187” push-on tabs

Epoxy Fill