Supplementary power supply unit to be used to supply local power to outdoor posts and prearranged indoor posts. 2-DIN modular housing. Power supply 230 Va.c. at 5060 Hz. Provides a low DC voltage output at 27 Va.c. with a max. current of 600 mA and protected on the PRI side with a NON-replaceable fuse against short circuit and overload. And a double-insulated SELV safety device.