Installation contactors are electromagnetically operated switches. If a control current flows through the magnetic coil, the magnetic attraction closes a main circuit. As long as the control current flows, the switch-on position is maintained. If the control current is interrupted, a spring forces the contacts to separate or return to their original position. This design ensures that contactors ensure galvanic isolation between the control circuit and the switched circuit, while at the same time being able to switch high currents. Installation contactors are only intended for isolation to a limited extent; they must be protected against overload and short circuits by upstream protective devices. Installation contactors of the HS series for distribution board installation are extremely low-hum and are characterized by very quiet switching processes, by their versatility due to their usage categories and by their long mechanical and electrical service life. The magnetic coil in this series is suitable for continuous operation (100% duty cycle). Devices of this design are operated with a control voltage of 24 V AC. Properties: - wide range of different contacts - long electrical and mechanical service life - extremely low hum - suitable auxiliary switch and sealing cap available Mounting type: - quick fastening on mounting rail - installation position as desired Areas of use: Installation contactors can be used in a variety of ways in residential and commercial buildings as well as industrial plants. They switch incandescent lamps, fluorescent lamps, transformers for low-voltage halogen lamps, high-pressure mercury vapor lamps (HQL, HPL), metal halide lamps (HQI, HPI), sodium vapor, low and high-pressure lamps, storage furnaces or drives (motors). Notes: - The designation of the devices in this series includes both the rated current (first pair of numbers) and the contact design (last pair of numbers): An HS 25-31 has