Door switching device that enables the setup of SimpleBus systems with more than 240 participants. Also suitable for systems serving multiple single-family homes with centralized door control and concierge station. The signal switch allows for cascading distribution of the bus line as an alternative to star distribution and optimizes the wiring topology of the system component from video mixer model 4888C. Features self-feeding of the input LS|LS for managing the riser without a special additional door station. Supply voltage 12V AC (compatible with model 1200) or 20V DC. Dimensions: 60 x 85 x 35 mm (4 DIN modules).