DIN-rail external module for 4 analogue outputs 4-20 mA (Mod. CONV 4/420/A for NT935 unit). The connection between the two devices is made through the serial bus Tecsybus (two- wire optically isolated), which grants a high level of protection against electromagnetic interferences. The 4-20 mA outputs are referred to the 4 temperatures detected by the unit in a range between 0°C and 240°C