PLM Series – Voltage Monitor Series - Littelfuse PLM Voltage Monitoring Relays Provide Superior Protection

Series: PLM Series – Voltage Monitor
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Littelfuse products are not designed for, and shall not be used for, any purpose (including, without limitation, automotive, military, aerospace, medical, life-saving, life-sustaining or nuclear facility applications, devices intended for surgical implant into the body, or any other application in which the failure or lack of desired operation of the product may result in personal injury, death, or property damage) other than those expressly set forth in applicable Littelfuse product documentation. Warranties granted by Littelfuse shall be deemed void for products used for any purpose not expressly set forth in applicable Littelfuse documentation. Littelfuse shall not be liable for any claims or damages arising out of products used in applications not expressly intended by Littelfuse as set forth in applicable Littelfuse documentation. The sale and use of Littelfuse products is subject to Littelfuse Terms and Conditions of Sale, unless otherwise agreed by Littelfuse. "Littelfuse" includes Littelfuse, Inc., and all of its affiliate entities.

The PLM series is a three-phase voltage monitor that continuously monitors each of the three phases. It monitors both delta and wye systems, and a connection to neutral is not required. The microcontroller circuit design protects against undervoltage, voltage unbalance, phase loss, and phase reversal. Protection is ensured when regenerated voltages are present.

Operation

The 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 Adjustment

Set the 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 three phases, voltage, and phase sequence. If the 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.

Features

  • Quick octal 8-pin mounting
  • Proprietary microcontroller-based circuitry
  • LED diagnostics
  • Isolated, 10 A, SPDT output contacts
  • Adjustable, nominal voltage set point
  • Simple 3-wire connection for delta or wye systems
  • ASME A17.1 Rule 210.6
  • NEMA MG1 14:30, 14:35
  • IEEE C62.41-1991 Level B

Product Literature

For Technical Questions

Call +1 800-832-3873 or email us at relays@littelfuse.com 

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)Input Phase SequenceInput TypeInput Voltage Maximum (V)Output Load Rating (VA)Output TypePhase LossPower ConsumptionReset Time (ms)StockSamplesCompare
PLM6405200 - 240 VacIsolated SPDTOctal 8-pin plug-in rated 600 VacPlug-in socket3.2 H x 2.39 W x 1.78 D in. (81.3 x 60.7 x 45.2 mm)0 Kg50 / 100A; B; C3-phase delta or WYE with no connection to neutral27010 A resistive @ 240 Vac 277 Vac max; 1/2 hp @ 240 Vac; 1/4 hp @ 120 VacElectromechanical relay≥35%≤2 WAutomaticCheckOrder
PLM6502200 - 240 VacIsolated SPDTOctal 8-pin plug-in rated 600 VacPlug-in socket3.2 H x 2.39 W x 1.78 D in. (81.3 x 60.7 x 45.2 mm)0 Kg50 / 100A; B; C3-phase delta or WYE with no connection to neutral27010 A resistive @ 240 Vac 277 Vac max; 1/2 hp @ 240 Vac; 1/4 hp @ 120 VacElectromechanical relay≥35%≤2 WAutomaticCheckOrder
PLM6805200 - 240 VacIsolated SPDTOctal 8-pin plug-in rated 600 VacPlug-in socket3.2 H x 2.39 W x 1.78 D in. (81.3 x 60.7 x 45.2 mm)0 Kg50 / 100A; B; C3-phase delta or WYE with no connection to neutral27010 A resistive @ 240 Vac 277 Vac max; 1/2 hp @ 240 Vac; 1/4 hp @ 120 VacElectromechanical relay≥35%≤2 WAutomaticCheckOrder
PLM8405360 - 430 VacIsolated SPDTOctal 8-pin plug-in rated 600 VacPlug-in socket3.2 H x 2.39 W x 1.78 D in. (81.3 x 60.7 x 45.2 mm)0 Kg50 / 100A; B; C3-phase delta or WYE with no connection to neutral48010 A resistive @ 240 Vac 277 Vac max; 1/2 hp @ 240 Vac; 1/4 hp @ 120 VacElectromechanical relay≥35%≤3 WAutomaticCheckOrder
PLM9405400 - 480 VacIsolated SPDTOctal 8-pin plug-in rated 600 VacPlug-in socket3.2 H x 2.39 W x 1.78 D in. (81.3 x 60.7 x 45.2 mm)0 Kg50 / 100A; B; C3-phase delta or WYE with no connection to neutral53010 A resistive @ 240 Vac 277 Vac max; 1/2 hp @ 240 Vac; 1/4 hp @ 120 VacElectromechanical relay≥35%≤3 WAutomaticCheckOrder
PLM9502400 - 480 VacIsolated SPDTOctal 8-pin plug-in rated 600 VacPlug-in socket3.2 H x 2.39 W x 1.78 D in. (81.3 x 60.7 x 45.2 mm)0 Kg50 / 100A; B; C3-phase delta or WYE with no connection to neutral53010 A resistive @ 240 Vac 277 Vac max; 1/2 hp @ 240 Vac; 1/4 hp @ 120 VacElectromechanical relay≥35%≤3 WAutomaticCheckOrder
PLM9805400 - 480 VacIsolated SPDTOctal 8-pin plug-in rated 600 VacPlug-in socket3.2 H x 2.39 W x 1.78 D in. (81.3 x 60.7 x 45.2 mm)0 Kg50 / 100A; B; C3-phase delta or WYE with no connection to neutral53010 A resistive @ 240 Vac 277 Vac max; 1/2 hp @ 240 Vac; 1/4 hp @ 120 VacElectromechanical relay≥35%≤3 WAutomaticCheckOrder
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