The PLM9405 is a 3-phase voltage monitor designed to protect against undervoltage, voltage unbalance, phase loss, and phase reversal in delta or wye systems without requiring a neutral connection. It features an 8-pin octal plug-in mount with dimensions of 81.3 mm in height, 60.7 mm in width, and 45.2 mm in depth. The unit operates on 480 VAC with a voltage range up to 530 VAC, has a fixed voltage unbalance trip point of 4%, and a fixed trip delay of 5 seconds. It includes an isolated 10A SPDT relay with a 277 VAC maximum rating, automatic reset, and LED diagnostics. The device complies with IEEE C62.41-1991 Level B surge protection, NEMA MG1 14:30, 14:35, and ASME A17.1 Rule 210.6. Power consumption is approximately 3 W, and it operates within a temperature range of -40°C to 60°C.
The PLM Series is a 3-phase voltage monitor that continuously monitors each of the three phases. Monitors both delta and wye systems and no connection to neutral is required. The microcontroller circuit design protects against undervoltage, voltage unbalance, phase loss and phase reversal. Protection is assured when regenerated voltages are present. OperationThe output relay is energized and the LED glows green when all voltages are acceptable and the phase sequence is correct. Under and unbalanced voltages must be sensed for a continuous trip delay period before the relay de-energizes. Reset is automatic upon correction of the fault condition. The output relay will not energize if a fault condition is sensed as power is applied. The LED flashes red during the trip delay, then glows red when the output de-energizes. The LED flashes green/red if phase reversal is sensed.Field AdjustmentSet voltage adjustment knob at the desired operating line voltage for the equipment. This adjustment automatically sets the undervoltage trip point. Apply power. If the PLM fails to energize, (LED glows red) check wiring of all 3 phases, voltage, and phase sequence. If phase sequence is incorrect, the LED flashes green/red. To correct this, swap any two line voltage connections at the mounting socket. No further adjustment should be required.
Industrial Relays 3PHASELINEMONITOR
Voltage Asymmetry, Voltage Sensing AC, Phase Loss 480VAC
| Littelfuse, Inc. | VAST STOCK CO., LIMITED | Quarktwin Technology Ltd. | |
|---|---|---|---|
| Product Category | Electromechanical Relays | Electromechanical Relays | Protective Relays and Monitoring Relays |
| Product Number | PLM9405 | PLM9405 | PLM9405 |
| Product Name | PLM Series – Voltage Monitor | Industrial Relays | Monitor - Relay Output |
| Mounting | Socket or Plug-in Style; Plug-in socket |
