For switching an electric circuit (lighting, heating) ON or OFF at selected times during a pre-programmed time periodTemporary (automatic return) or permanent (forced switching ON or OFF) override on outputFor autonomous control of outdoor illuminationsAutomatic programming: simply initialise the products for the location with no need to install a photoelectric cellProgrammed directly on keypad, or using programme transfer key Cat.No 4 128 27High precision clock: ± 0.2 sec per day