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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
    User Manual
    VME420    		 English 12.2009
    Download
    Brochure
    Overview - Protection Relays    		 English 04.2013
    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
    User Manual
    VMD420    		 English 01.2010
    Download
    Brochure
    Overview - Protection Relays    		 English 04.2013
    Download
    3D STEP Drawing
    420 Series (Standard)    		 N/A 06.2013
    Download

  • Accessories: VMD420

  • 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 - Protection Relays    		 English 04.2013
    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 - Protection Relays    		 English 04.2013
    Download

  • Accessories: VMD421H