External electrical connection Vallox 51 MV MB_A External Modbus A signal MB_B External Modbus B signal +24V +24V voltage (DC) GND Digital and analog ground potential RS_A Local hardware Modbus A signal RS_B Local hardware Modbus B signal NTC External temperature sensor connector D/I1 Digital input 1 D/I2 Digital input 2 11V1 11.1 V operating voltage AN/I Analog input 0-10 VDC RM/I 24V relay input RM/O 24V relay output Table 1. Power supply Object Feed Maximum ≤6W MyVallox Control 1 W MyVallox RH% sensor 0.3W MyVallox CO2 sensor 1.2W Voltage 24 VDC