Matsuo M2 & M3 Precision Thermostats

Matsuo M2 and M3 high accuracy bimetal thermostats offer higher switching capacities than the smaller MQT8K series.  Loads up to 3A/250VAC or 5A/125VAC can be readily switched with tight differentials and tolerances.

The M2 thermostat is a lower-profile version of the M3 and is only available with a 10K differential whereas the M3 can have a temperature switching differential as small as 3.5±1.5K.  Both parts can be specified with calibrations from -10°C to +110°C in one degree steps and set-point tolerances down to ±3K.

The M2 has no mounting holes and is slimmer than the M3 which has 2 mounting holes to assist surface fixing.  Both types can be supplied with either normally closed or normally open contact operation.


  • Defrost and anti-freezing trace heating circuits
  • Anti-condensation e.g. in CCTV applications
  • Over-temperature control in ATEX applications
  • Flexible heaters and industrial heating elements


  • Temperature settings from -10°C to +110°C
  • Normally closed or normally open contacts
  • Switching capacities: 3A/250VAC or 5A/125VAC
  • M2 Case size 45.5 x 16 x 7.5mm
  • M3 Case size 45 x 15.5 x 10.8mm
  • Dual mounting bracket option
Matsuo high accuracy bimetal switching thermostats Matsuo M2 & M3 Technical Drawings