What is a Piggy-Back Switch?
The PIGGY-BACK plug design enables the pump to be used as either an AUTOMATIC PUMP or a MANUAL PUMP. To have the pump start/stop automatically, plug the pump into the switch's piggy-back plug and plug both plugs into the wall outlet (see automatic illustration). To switch to manual mode, just unplug the pump from the switch plug and plug the pump directly into a wall outlet (see manual illustration).
Manual mode allows you to run the pump immediately regardless of how high the water level is. This is used primarily for emergency water removal or for testing the switch operation.