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Protective Relays

Voltage and Frequency Relays

BENDER's line of voltage relays are powerful, fully-featured devices which can monitor overvoltage, undervoltage, overfrequency and underfrequency from a single device. Three-phase versions also monitor phase sequence and failure. These compact devices feature digital displays showing values in real-time and also allow for entering precise alarm values.
  • Description
  • Features
  • Applications
  • Ordering Info
  • Downloads
  • Accessories

  • VME420

    Digital voltage and frequency relay for single-phase AC and DC systems

    The VME420 is a powerful, all-in-one unit for single-phase AC and DC systems for 0 to 300 V monitoring over/undervoltage and over/underfrequency. Values are displayed and changed via a digital seven-segment display and menu. Values are displayed as true RMS values, and many different delays can be set.

    The VME420 unit utilizes an auxiliary supply voltage to power itself. For the version that is powered off of the monitored line, please see the VME421H.

  • Key Features: VME420

    • Overvoltage, undervoltage, overfrequency, and underfrequency monitoring for single-phase AC and DC systems
    • True RMS readings
    • Digital display with values shown in real-time
    • Separately adjustable alarms for each alarm type
    • Onboard menu for settings; explicit trip values can be entered in
    • Two SPDT contact outputs, independently configurable to any combination of alarm types
    • Separately adjustable time delays for response delay, startup delay, and delay on release
    • Built-in test and reset buttons
    • Latching or non-latching operation, selectable
    • Normally energized or normally de-energized operation, selectable
    • Last tripped alarm value stored in memory
    • Auxiliary supply voltage inputs

  • Applications: VME420

    • General applications requiring overvoltage / undervoltage protection
    • Generators, portable and fixed
    • Battery backup systems
    • Motor overvoltage protection

  • Ordering information: VME420

    NameSystem Voltage0...400 μA analog output0(4)...20 mA analog output0...10 V analog outputSPDT contact outputSupply VoltageOrdering Number
    VME420-D-1AC 0 - 300 V (15 - 460 Hz) DC 0 - 300 V 2AC 16 - 72 V (15 - 460 Hz) DC 9.6 - 94 V B93010001
    VME420-D-2AC 0 - 300 V (15 - 460 Hz) DC 0 - 300 V 2AC 70 - 300 V (15 - 460 Hz) DC 70 - 300 V B93010002
    VME420-DM-1AC 0 - 300 V (15 - 460 Hz) DC 0 - 300 V 1AC 16 - 72 V (15 - 460 Hz) DC 9.6 - 94 V B93010015
    VME420-DM-2AC 0 - 300 V (15 - 460 Hz) DC 0 - 300 V 1AC 70 - 300 V (15 - 460 Hz) DC 70 - 300 V B93010016

  • Downloads: VME420

    Document Name Language Date Download
    Technical Bulletin / Datasheet
    VME420    		 English 02.2010
    Download
    Installation Bulletin
    VME420    		 English 10.2012
    Download
    Menu Overview / Settings Checklist
    VME420    		 English 08.2013
    Download
    User Manual
    VME420    		 English 12.2009
    Download
    Brochure
    Overview of Products    		 English 06.2017
    Download
    3D STEP Drawing
    420 Series (Standard)    		 N/A 06.2013
    Download

  • Accessories: VME420

  • Description
  • Features
  • Applications
  • Ordering Info
  • Downloads
  • Accessories

  • VMD420

    Digital voltage and frequency relay for three-phase AC systems

    The VMD420 is a powerful, all-in-one unit for monitoring three-phase AC systems up to 500 V. The VMD420 is capable of monitoring for overvoltage and undervoltage, overfrequency and underfrequency, asymmetry, phase sequence, and phase loss. Values are displayed and changed via a digital seven-segment display and menu. Values are displayed as true RMS values, and many different delays can be set.

    The VMD420 unit utilizes an auxiliary supply voltage for power. For the version that is powered off of the monitored line, please see the VMD421H.

  • Key Features: VMD420

    • Overvoltage, undervoltage, overfrequency, and underfrequency, asymmetry, phase sequence, and phase loss monitoring for three-phase AC systems
    • True RMS readings
    • Digital display with values shown in real-time
    • Separately adjustable alarms for each alarm type
    • Onboard menu for settings; explicit trip values can be entered in
    • Two SPDT contact outputs, independently configurable to any combination of alarm types
    • Separately adjustable time delays for response delay, startup delay, and delay on release
    • Built-in test and reset buttons
    • Latching or non-latching operation, selectable
    • Normally energized or normally de-energized operation, selectable
    • Last tripped alarm value stored in memory
    • Auxiliary supply voltage inputs

  • Applications: VMD420

    • General applications requiring overvoltage / undervoltage protection
    • Generators, portable and fixed
    • Monitoring of industrial distribution systems
    • Motor overvoltage and phase loss protection

  • Ordering information: VMD420

    NameSystem Voltage0...400 μA analog output0(4)...20 mA analog output0...10 V analog outputSPDT contact outputSupply VoltageOrdering Number
    VMD420-D-1AC 0 - 500 V (15 - 460 Hz) 2AC 16 - 72 V (42 - 460 Hz) DC 9.6 - 94 V B93010005
    VMD20-D-2AC 0 - 500 V (15 - 460 Hz) 2AC 70 - 300 V (42 - 460 Hz) DC 70 - 300 V B93010006
    VMD420-DM-1AC 0 - 500 V (15 - 460 Hz) 1AC 16 - 72 V (42 - 460 Hz) DC 9.6 - 94 V B93010017
    VMD420-DM-2AC 0 - 500 V (15 - 460 Hz) 1AC 70 - 300 V (42 - 460 Hz) DC 70 - 300 V B93010018

  • Downloads: VMD420

    Document Name Language Date Download
    Technical Bulletin / Datasheet
    VMD420    		 English 04.2011
    Download
    Installation Bulletin
    VMD420    		 English 10.2012
    Download
    Menu Overview / Settings Checklist
    VMD420    		 English 08.2013
    Download
    User Manual
    VMD420    		 English 01.2010
    Download
    Brochure
    Overview of Products    		 English 06.2017
    Download
    3D STEP Drawing
    420 Series (Standard)    		 N/A 06.2013
    Download

  • Accessories: VMD420

  • Description
  • Features
  • Applications
  • Ordering Info
  • Downloads
  • Accessories

  • VMD258

    Voltage relay for three-phase AC systems

    The VMD258 series voltage relay monitors for undervoltage and overvoltage in threephase AC systems. Both overvoltage and undervoltage are monitored for simultaneously. Alarm values are set as a percentage of the system voltage (see ordering information for more). Power for the monitoring is derived from the monitored system; an external supply voltage is not required. Many different system voltage ratings are available, up to 690 VAC. 2 DPDT contact outputs are available.

    The device contains analog-only components and is not microprocessor controlled. The supply of the electronics and relays are isolated by means of double isolation. Special input transformers attenuate system interferences.

  • Key Features: VMD258

    • Overvoltage and undervoltage monitoring in three-phase AC systems up to 690 VAC
    • Analog-only device, non-microprocessor controlled; perfect for utilities and other mission critical areas
    • Overvoltage and undervoltage alarms operate simultaneously (window function)
    • Adjustable undervoltage alarm, 70 - 95% of rated system voltage
    • Adjustable overvoltage alarm, 105 - 130% of rated system voltage
    • 0 - 5 second adjustable time delay
    • 2 DPDT contact outputs, normally energized or de-energized depending on alarm type
    • Line-powered, no separate supply voltage required

  • Applications: VMD258

    • General applications requiring overvoltage / undervoltage protection
    • Utilities
    • Faciltiies and applications requiring non-microprocessor controlled monitoring equipment
    • Motors, pumps, generators

  • Ordering information: VMD258

    NameSystem VoltageOrdering Number
    VMD258 100V 3PH100 V B93010060
    VMD258 110V 3PH110 V B93010061
    VMD258 230V 3PH230 V B93010062
    VMD258 400V 3PH400 V B93010063
    VMD258 440V 3PH440 V B93010064
    VMD258 480V 3PH480 V B93010065
    VMD258 500V 3PH500 V B93010066
    VMD258 690V 3PH690 V B93010067

  • Downloads: VMD258

    Document Name Language Date Download
    Technical Bulletin / Datasheet
    VMD258    		 English 07.2014
    Download
    Installation Bulletin
    VMD258    		 English 07.2014
    Download
    Brochure
    Overview of Products    		 English 06.2017
    Download

  • Accessories: VMD258

  • Description
  • Features
  • Applications
  • Ordering Info
  • Downloads
  • Accessories

  • VME421H

    Digital voltage and frequency relay for single-phase AC and DC systems

    The VME421H is a powerful, all-in-one unit for single-phase AC and DC systems for up to 300 V, monitoring over/undervoltage and over/underfrequency. Values are displayed and changed via a digital seven-segment display and menu. Values are displayed as true RMS values, and many different delays can be set.

    The VME421H unit powers itself off of the line being monitored. For the version that utilizes an external supply voltage, please see the VME420.

  • Key Features: VME421H

    • Overvoltage, undervoltage, overfrequency, and underfrequency monitoring for single-phase AC and DC systems
    • True RMS readings
    • Digital display with values shown in real-time
    • Separately adjustable alarms for each alarm type
    • Onboard menu for settings; explicit trip values can be entered in
    • Two SPDT contact outputs, independently configurable to any combination of alarm types
    • Separately adjustable time delays for response delay, startup delay, and delay on release
    • Built-in test and reset buttons
    • Latching or non-latching operation, selectable
    • Normally energized or normally de-energized operation, selectable
    • Last tripped alarm value stored in memory
    • Powers itself from monitored lines

  • Applications: VME421H

    • General applications requiring overvoltage / undervoltage protection
    • Generators, portable and fixed
    • Battery backup systems
    • Motor overvoltage protection

  • Ordering information: VME421H

    Name0...400 μA analog output0(4)...20 mA analog output0...10 V analog outputSPDT contact outputSupply VoltageOrdering Number
    VME421H-D-12AC 9.6 - 150 V (15 - 460 Hz) DC 9.6 - 150 V B93010003
    VME421H-D-22AC 70 - 300 V (15 - 460 Hz) DC 70 - 300 V B93010004
    VME420-DM-11AC 9.6 - 150 V (15 - 460 Hz) DC 9.6 - 150 V B93010024
    VME420-DM-21AC 70 - 300 V (15 - 460 Hz) DC 70 - 300 V B93010010

  • Downloads: VME421H

    Document Name Language Date Download
    Technical Bulletin / Datasheet
    VME421H    		 English 03.2013
    Download
    Installation Bulletin
    VME420    		 English 10.2012
    Download
    User Manual
    VME421H    		 English 01.2010
    Download
    Brochure
    Overview of Products    		 English 06.2017
    Download

  • Accessories: VME421H

  • Description
  • Features
  • Applications
  • Ordering Info
  • Downloads
  • Accessories

  • VMD421H

    Digital voltage and frequency relay for three-phase AC systems

    The VMD421H is a powerful, all-in-one unit for monitoring three-phase AC systems up to 500 V. The VMD420 is capable of monitoring for overvoltage and undervoltage, overfrequency and underfrequency, asymmetry, phase sequence, and phase loss. Values are displayed and changed via a digital seven-segment display and menu. Values are displayed as true RMS values, and many different delays can be set.

    The VMD421H unit powers itself off of the line being monitored. For the version that utilizes an external supply voltage, please see the VMD420.

  • Key Features: VMD421H

    • Overvoltage, undervoltage, overfrequency, and underfrequency, asymmetry, phase sequence, and phase loss monitoring for three-phase AC systems
    • True RMS readings
    • Digital display with values shown in real-time
    • Separately adjustable alarms for each alarm type
    • Onboard menu for settings; explicit trip values can be entered in
    • Two SPDT contact outputs, independently configurable to any combination of alarm types
    • Separately adjustable time delays for response delay, startup delay, and delay on release
    • Built-in test and reset buttons
    • Latching or non-latching operation, selectable
    • Normally energized or normally de-energized operation, selectable
    • Last tripped alarm value stored in memory
    • Powers itself from monitored lines

  • Applications: VMD421H

    • General applications requiring overvoltage / undervoltage protection
    • Generators, portable and fixed
    • Monitoring of industrial distribution systems
    • Motor overvoltage and phase loss protection

  • Ordering information: VMD421H

    NameSystem Voltage0...400 μA analog output0(4)...20 mA analog output0...10 V analog outputSPDT contact outputOrdering Number
    VMD421H-D-3AC 70 - 500 V (15 - 460 Hz) 2B93010007
    VMD421H-DM-3AC 70 - 500 V (15 - 460 Hz) 1B93010023

  • Downloads: VMD421H

    Document Name Language Date Download
    Technical Bulletin / Datasheet
    VMD421H    		 English 10.2011
    Download
    Installation Bulletin
    VMD421H    		 English 10.2012
    Download
    User Manual
    VMD421H    		 English 03.2010
    Download
    Brochure
    Overview of Products    		 English 06.2017
    Download

  • Accessories: VMD421H