Temperature monitor system for cast resin, dry and oil transformers with 4 inputs for 3 wires PT100 probes.

  • Control and showing temperature
  • Control of fan systems
  • Four independent PT100 inputs with three wires
  • Four 250 Volt 10A AC (resistive load) relays of outputs for the
    following functions: pre alarm state, alarm state, fault probe state,
    fan control with hysteresis
  • Manual test relays to simulate or check the reliability of the contact
  • Advanced programming menu: is allowed able, enable and set
    separately each single channel
  • Permanent storing of programmed set of pre-alarm and alarm
    state, on, off fan and history values achieved
  • Assembly on panel by simple fixing jaws
  • Universal power supply (24 ÷ 240) Volt AC/DC 50/60Hz
  • Protocol MODBUS – RTU, RS 485 communication (MT 200 S)
  • Protocol MODBUS – RTU, RS 485 communication and galvanically
    insulated analogical output 4-20 mA (MT 200 C)
  • Protocol MODBUS – TCP, ETHERNET communication (MT 200 E)
  • Tropicalization (optional)


MT 200
Temperature controller device, 4 inputs PT100 probes, 4 relays


MT 200 50121-5
Temperature controller device, 4 inputs PT100 probes, 4 relays according to EN 50121-5 rule


MT 200 S
Temperature controller device, 4 inputs PT100 probes, 4 relays, serial communication RS485 half duplex, MODBUS-RTU protocol


MT 200 C
Temperature controller device, 4 inputs PT100 probes,
4 relays, analogical communication 0-20 or 4-20 mA and serial communication RS485 half duplex, MODBUS-RTU protocol


MT 200 E
Temperature controller device, 4 inputs PT100 probes, 4 relays, ETHERNET communication, MODBUS-TCP protocol


Technical features


  • Box 90x90x115 mm included terminal blocks
  • Front panel 96×96 mm
  • Weight 0,4 Kg

Power Supply

  • Power supply (24 ÷ 240) Volt AC/DC ± 10% 50/60 Hz without polarity respect, absorption 4 VA


  • Four analogical inputs, temperature control and mapping with PT100 sensor at three wires inside range from -10°C to +200°C


  • Four relays 250V AC, 10 A max (resistive load), free switch contact
  • RS485 Half Duplex protocol MODBUS-RTU (MT 200 S)
  • RS485 Half Duplex protocol MODBUS-RTU, 4-20 mA or 0-20 mA galvanically isolated (MT 200 C)
  • ETHERNET communication port, protocol MODBUS – TCP (MT 200 E)


  • Self-extinguishable NORYL Box
  • Protection degree front panel in polycarbonate: IP65
    (IP66 on request)
  • Protection degree of rear panel on terminal board side:
  • Display with light segments
  • Visualisation of max temperature and the relevant
    channel in the automatic mode
  • Alerts of pre-alarm, alarm, probes fault, fanning, manual
    function, historic highs
  • System programming directly by frontal panel
  • Possibility to select independently each channel
  • Limit of alarm and pre-alarm settable in the range
    (-9°C ÷ 199°C)
  • Precision ± 1% on full-scale ± 1 digit
  • Cooling fan control on three or four channels
  • Comparison of temperature for cooling fan between two
    different levels (L and H)
  • Four selectable operating modes
  • Detection of fault probes, maximum flexibility of
    managing and simplicity of programming, checking of
    validity of the insert data during programming phase
  • Continuos storage of planned and reached values by
    each channel (limits and historic highs)
  • Dielectric isolation: 2,5 KV AC for 60”
  • Software configuration to control the environment
  • Resolution 1°C
  • Working temperature of device from -20°C to 60°C
  • Max allowed dampness in the room 90% not condensing
  • Electrical connections with fast-polarised connectors
  • Possibility of manual relays switch through menu test
    relays to simulate and check the reliability of contact
  • Galvanically insulated output 4-20 mA or 0-20 mA
    (MT200 C)
  • Maximum impedance allowed for current output
    500 Ohm
    Range 4-20 mA (-10°C 4 mA / +200°C 20 mA)
    Transformation formula (current in mA, temperature in
    °C): lout = (T+10)/210*16 + 4
    Range 0-20 mA (-10°C 0 mA / +200°C 20 mA)
    Transformation formula (current in mA, temper ature in
    °C): lout = (T+10)/210*20 (MT200 C)
  • Certification for railway environment use according to
    EN-50121-5:2006 regulations (MT 200 EN50121-5)
  • Configuration of IP address, port, subnet, gateway via
    browser web (MT200 E)
  • Technical manual in five languages
    (and more on request)
  • Construction in accordance with rule EN61000-6-2:2005 2014/30/EU
  • Input filter for power supply in accordance with rules
  • Tropicalization (optional)