The Electronic Condensate Overflow Switch contains low power consuming, state-of-the-art microelectronics. SS103E can be installed horizontally or vertically, inline or on the primary pan"s auxiliary drain outlet by using the included ¾" adapter, bushing and cap. An additional sensor can be installed in the auxiliary drain pan. SS103E provides the added protection of dual sensor control with the simplicity of installing a single 2-wire device. No moving parts, simply connect to the yellow wire.The logic circuit continuously samples the probes for water. If water is detected, the circuit determines if the condition is transient or permanent. If permanent, the system will be shutdown. Onboard LED"s indicate the condition of the unit at a glance, removing any guess work. Listed to UL 508.