PCU Input unit for impulse push buttons (momentary push buttons) with integrated power supply for 25 DALI units. Connected to 230 V, impulse push button and DALI. Two PCUs can be connected to power a maximum of 50 DALI units. Four units can be connected in parallel for control from multiple locations. PCU Input unit’s must not be combined with other DALI control units. PCU also has settings for different starting conditions after a power failure.