Sensor module insert for mounting in the VLTM mounting rail. Additional modules VLMF ... made of extruded aluminum profile, white, silver (-SI) or black (-SW), powder-coated. Spring steel clips for fastening to the mounting rail. The VLMF ... modules can be placed variably between the VLGF ... device carriers. Electrical adapter for flexible tapping of the power supply in the mounting rail. Color and optical coding for easy installation. Mechanical coding to prevent incorrect installation (twisting protection). Device carrier sensor module with multi-sensor BEG PD4 or CDS (DALI twilight switch), including cover slats/blinds. Configurations of setpoint, run-on time, etc. can be carried out on the sensor.