switch 33 successively steps through the devices ed 1 ed 2 and ed 3 for individual programming in fig5 ed 1 has been selected as indicated by the led 24 actuating the u201c period u201d switch 35 has selected period 3 as indicated by the led 29 selectively holding the u201c time on u201d switch 36 led 30 lit cycles the clock readout shown in the lcd 32 to set the start time of period 3 for ed 1 subsequently selectively holding the u201c time off u201d switch 37 led 31 lit will cycle the clock readout shown in the lcd 32 to set the end time of period 3 for ed 1 15 a the u201c on u201d and u201c off u201d periods for ed 2 15 b and ed 3 15 c are similarly set as an example assume that ed 1 15 a has been set to have three u201c on u201d periods of 6 30 7 30 pm p 1 10 00 10 25 pm p 2 and 5 30 8 00 am p 3 ed 2 15 b has been set to have two u201c on u201d periods of 7 00 10 30 pm p 1 and 6 30 8 00 am p 2 and ed 3 15 c has been set to have a single u201c on u201d period of 7 00 11 30 pm thus when the system is in vacation mode the various lights will cycle in a manner consistent with the conditioned space being occupied and according to their individual placements to provide a deterrent to mischief consider now the various configurations for practicing the invention in the basic configuration of fig1 all the.