Auxiliary switches report the status of the main devices on which they are mounted. The DHi 12 auxiliary switch is suitable for FI/LS combinations of the DRCBO 3 series, the DAFDD 1 arc fault protection device and the ELS 3 series miniature circuit breakers. In auxiliary switch mode, it signals the switching on and off of the circuit breaker. In fault signal switch mode, it signals the tripping. Properties: Auxiliary and fault signal switch function, can be retrofitted, small size, Mounting type: to the left of the base unit by snapping onto the main unit, quick fastening to the mounting rail, installation position as desired, Areas of use: These devices are suitable for querying the operating status of power supplies in residential and commercial buildings as well as industrial plants. Notes: The auxiliary switch does not affect the function of the base unit.