The M 4 Vigitherme is made up of a stainless steel case and a nylon body carrying the connecting screw terminals. The parts under tension are insulated from the ground of the apparatus. The bi-metallic disc is located at the bottom of the stainless steel case which then constitutes the portion sensitive to temperature.
A M 4 B version that does not return to initial state by cooling is also available. To reactivate it, it is necessary to press the red button located in the middle.
Types of contacts : opening - closing - inversor
Composition of contacts : solid silver
Voltage proof between terminations and ground : 4000 V
Contact resistance : 6 m Ohm
Connection : screw terminals