What Meter Bus MBUS M-Bus EN 13757 is?
Meter Bus is a European standard for the remote reading of meters (heat, water, gas, energy, electricity, etc.). The European Union has codified it with the number EN 13757. 
It is also known as M-bus or MBUS for short. 
Meter Bus is a bus to which various measuring devices can be connected, and works with two wires, for example it can use a simple telephone twisted pair or a ribbon, and generally uses 3.81 mm industrial connectors (or even different connectors). 
Theoretically the connection can be hundreds of meters; the voltage can range from 36 nominal to a minimum of 12V. 
interfaccia mbus connettore 
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