PURPOSE: To enable application of a transformer of low capacity by using a plurality of relays freely formed into a group.

CONSTITUTION: A plurality of relays are contained in a relay block 11 to control a plurality of illumination loads L1 to Ln. The relay is controlled by a control block 13 containing a delay block 14 and an ON/OFF block 15. The delay block 14 is constituted such that a plurality of outputs 1 to(n)can be used freely through a group relating to a plurality of inputs 1 to (m). An output from the delay block 14 is given to the relay block 11 through the ON/OFF block 15 by which an ON/OFF condition can be set in each of a plurality of the relays. Since a control signal delayed by the delay block 14, is given relating to the relays simultaneously operated by input switches 16, 17, 18, capacity of a power transformer 12 can be decreased.