Dold Industries Ltd

11 Hamberts Rd. Blackall Ind. Estate
South Woodham Ferrers
GB-Essex, CM3 5UW
MK 9055N/5__

Speed monitor

MK 9055N/5__


Auxiliary voltage

Start up delay

Response value


Approvals and Markings


  • 0058718
  • MK9055N.38/500 1-120000IPM Hyst.=5%
The speed monitors MK 9055N/5_ _ und MH 9055/5_ _ monitors the rotational speed of motors. They... more

Product description

The speed monitors MK 9055N/5_ _ und MH 9055/5_ _ monitors the rotational speed of motors. They recognise and monitor impulse signals of e. g. proximity sensors and protect machines and produced material or allows speed depending switching in production processes.

Technical specifications

Width: 22,5 mm
Measuring range max.: 120000 IPM
Auxiliary voltage: AC, DC
Classification: Drehzahlüberwachung
Output contacts: 2 x 1 C/O contacts
Enclosure design: Switch cabinet
Type: MK 9055N/5__


  • Protection of persons, machines and products
  • Easy setting
  • Universal input, for configuration of different sensors (PNP, NPN, 2-wire, contact, voltage)
  • With fast reaction at low speed


  • According to IEC/EN 60255-1
  • Monitoring of 2 frequency levels (e.g. underspeed / standstill and overspeed)
  • Separate relay outputs for under- and overfrequency (1 or 2 c/o contacts each)
  • As alternative window operating mode (monitoring of a speed range)
  • Response value for over- and underspeed / frequency separately adjustable in 10 ranges 1 ... 120.000 IPM or 0,15 ... 20.000 Hz
  • Most fast reaction time also at low speed by time period measurement of the input frequency
  • As option with input for NAMUR-sensors with sensor and wire protection against interruption and short circuit
  • Programmable via termminals:
    - Start up time delay 0 ... 50 s or controllable
    - Alarm delay time of 0 or 0.5 s
    - With manual reset or auto reset
  • LED-indication for auxiliary voltage, measuring input and output relay; additional LED for indication of wire- / sensor failure at NAMUR-input
  • Auxiliary voltages AC 230 V and DC 24 V in one unit
  • MH 9055 with wide input range for auxiliary voltage AC/DC 24 ... 60 V or AC/DC 110 ... 230 V (only 2 x 1 C/O)
  • As option with analogue output, proportionally to speed
  • 2 possible contacts
    MK 9055N/5_ _ 2 x 1 changeover contacs
    MH 9055/5_ _: 2 x 2 hangeover contacs or wide range aux. voltage
  • 2 possible compact designs
    MK 9055N/5_ _: Width 22,5 mm
    MH 9055/5_ _: Width 45 mm