Elitech EK-3030E Temperature Controller Thermostat With Sensor For USA Canada 110V Display panel can display three digits, two status indicator ( key lock and fan ) , four parameters descriptors ( temp on , temp off , def cycle , def time ). key operation within 30seconds, the controller will lock automatically. In the setting mode, press and release the key &nbsp;or no key operation within 30seconds, it will exit from setting mode and save the parameters.