KNX power supplies generate and monitor the KNX system voltage (SELV). The bus line is decoupled from the power supply by an inte-grated choke. The voltage output is short-circuit and overload protect-ed. The two-colour LED indicates device output status. Device type ITR900-6000 has an additional 30 V DC short-circuit and overload protected voltage output that can be used to power an additional bus line (in combination with a separate choke).