When voltage is applied to the input, the internal relay energizes and the ON timeT1 begins. Upon completion of the ON time, the relay de-energizes and the OFF time T2 begins. At the completion of the OFF time, one ON/OFF cycle is completed. This cycling action continues until voltage is removed from the input. The ON/OFF ratio is adjustable from 0 to 100 percent of time base. 0% is OFF; 100% is ON. Reset is accomplished by interrupting the input voltage.