Measuring & monitoring heavy duty, power relays

MTDV4 relay - Voltage monitoring, timer delay-on -off, 4 pole



Plug-in electronic voltage monitoring relay with optional delay-on and delay-off timer function and four change-over contacts. The delay time is adjustable with a lockable knob (either delay-on or delay-off, the other delay is fixed). The relay can also be supplied with fixed time delays (no knob). The pull-in voltage and drop-out voltage are both adjustable via internal screws. The relay can also be supplied with a fixed pull-in and drop-out voltage. Suitable for monitoring DC voltages.
The MTDV4 offers a very small hysteresis (difference between pull-in and drop-out voltage). The relay is equipped with a LED which indicates the status of the relay contacts. Delay-off function for voltage drop up to 50% nominal voltage, no auxiliary supply necessary. Magnetic arc blow-out for high breaking capacity and long contact life optional.
The construction of the relay and choice of materials makes the MTDV4 relay suitable to withstand low and high temperatures, shock & vibrating and dry to humid environments. No external retaining clip needed as integrated ‘snap-lock’ will hold relay into socket under all circumstances and mounting directions.


These relays are designed for demanding applications. The MTDV4 relay is used in applications for voltage monitoring with or without time delay(s).


  • DC voltage monitoring relay with time delay
  • Compact plug-in design
  • 4 C/O contacts
  • Pull-in and drop-out voltage adjustable via internal screws
  • Also available with fixed pull-in and drop-out voltage (no internal screws)
  • Very small hysteresis possible
  • Time delay on pull-in and/or drop-out
  • 1 delay time adjustable with a lockable knob, other delay time fixed
  • Also available with fixed time delays (no knob)
  • Time delay range: 0 ... 60 s
  • No auxiliary supply necessary
  • 1 LED for status indication
  • Flat, square and silver plated relay pins for excellent socket connection
  • Integrated snap lock
  • Optional positive mechanical keying relay to socket

Industry compliancy

  • IEC 61810 Electromechanical elementary relays
  • IEC 60947 Low voltage switch gear and control gear
  • IEC 60947-5-1 Electromechanical control circuit devices and switching elements
  • IEC 60255 Relay design and environmental conditions
  • EMS Directive
  • CE

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