Varimeter PRO, the multifunctional measuring relay 

Universal measuring relays MK 9300N / MH 9300

Complex processes in automation, process and industrial building systems, together with increasing demands in energy and environmental engineering require high operating reliability and permanent availability of the system.

The universal measuring relays MK 9300N / MH 9300 of the VARIMETER PRO series monitor up to 9 different parameters simultaneously. Quite simply and without much wiring effort. Whether simultaneous overvoltage/undervoltage, voltage asymmetry, overcurrent/undercurrent, cos phi, active power, apparent power and reactive power, frequency and phase sequence in three-phase and single-phase networks – a measuring relay for all scenarios.

Thanks to its menu structure the measuring relay can be operated easily and intuitively.

Varimeter PRO
Varimeter geïnstalleerd

Your benefits at a glance

  • Simultaneous monitoring of up to 9 measured variables
  • Overvoltage, undervoltage or window monitoring
  • Simple parameterization and fault diagnostics on the device
  •  Differentiated fault messages
  • Large measuring range 3 AC 24 … 690 V
  • Large auxiliary voltage range DC 24 V, AC 230 V or AC/DC 110 … 400 V
  • Variable terminal configurations through plug-type screw or spring-loaded terminals

Multifunctional measuring relay obtains DNV-GL certification

The multifunctional measuring relay MK 9300N from DOLD has been certified for use on ships by DNV-GL, one of the world’s leading maritime classification companies.

The component certificate provides proof that the multifunctional measuring relay complies with all guidelines. The safety, functional and quality requirements of the product have been tested in accordance with the DNV-GL regulations and found to be seaworthy.

The multifunctional measuring relay MK 9300N of the VARIMETER PRO series saves costs, space and wiring. It combines up to nine monitoring functions in an enclosure only 22.5 mm wide. This universal measuring and monitoring relay, therefore, offers an unprecedented range of functions at this minimum width.

DNV-GL certificaat
Hartslag op monitor

Maximum output function for your application

Precise monitoring and diagnosis in machines and plants have gained increasing significance over the past years.

The early detection of impending failures and preventive maintenance prevent costly damages. The VARIMETER PRO is the basis for reliable monitoring. As a user, you will benefit from the operating reliability and high availability of your system.

Secure this economic advantage.

Underneath you can find some examples:


Refrigeration lorry

Connecting the refrigeration unit of the lorry to the mains during loading and unloading to preserve the vehicle battery. Solution: Monitoring for correct phase sequence of the three-phase current supply to prevent the compressor from sustaining damage. Advantage: Disruption of the cooling chain of the cargo is prevented


Pumping unit

The pump motors must be switched off when one phase fails. Solution: Monitoring for asymmetry and undervoltage. After the voltage returns the individual pumps shall be switched on again in a staggered time frame. Advantage: Preventing motor damages due to overheating. Relief of the feeding mains by pump start with a time offset


Signal systems

Absolute operating reliability is required for traffic lights, obstacle and tarmac lighting. Solution: Monitoring of undercurrent to detect disconnects or defective loads. Advantage: Preventing fatal consequences for traffic safety. The response thresholds can be adjusted individually to the load to be monitored.


Fan drives

Ventilatoren en blowers worden vaak aangedreven via V-riemen. Een gescheurde V-riem of verstopping van het filter onderbreekt de continue stroom van het toedieningsmedium. Oplossing: bewaking van onderbelasting met cos-guard. Voordeel: uitgeven met externe sensoren. bijv. druktransmitters. Snelle correctie van de storingen door tijdige waarschuwing van het servicepersoneel.

Molen aandrijving

Mill drives

Grote aandrijvingen zoals graan- of cementfabrieken maken vaak nog gebruik van sleepringrotormotoren. Oplossing: gebruik een frequentiemonitor om de aanloop te regelen. Voordeel: een zachte start van de werkuitrusting behoudt de mechanische aandrijfelementen en voorkomt stroompieken in het voedingsnet.



Granulators and crushers must be monitored for material jams or blockage because machine and motor would be at risk in these conditions. Solution: Measuring the active power consumed or overload or under load. Advantage: Preventing overheating and thus winding damages of the motor. Energy savings through automatic cut-off of the drive during work breaks. Preventing mechanical damages through the timely shut-off of the drive.

Technical data Multifunctional relay

  • According to EN 60255, VDE 0435
  • Voltage monitoring (1-phase and 3-phase), current monitoring and frequency monitoring
  • Active, reactive and apparent power
  • Startup and response delay
  • Adjustable hysteresis at MH 9300 for Relay 1. Relay 2 is separately adjustable
  • LCD display for the current measured values
  • Relay function load current/standby current selectable
  • Optional with plug-in terminal blocks for quick device exchange
  • MK 9300N: 1 changeover contact, width only 22,5 mm, MH 9300: 2 x 1 changeover contact,width only 45 mm
Varimeter apparaat instellingen