Heavy-duty bypass
Priority switch is the external way to create an automatic selection of the power supply. It has two outputs: the first is for connecting all the appliances to be used only when the mains power supply is active, e.g. air conditioners, refrigerators and heavy-duty appliances you don't want to connect to power up with the leisure battery. The second output is for all the accessories that you want to be powered all the time, by both the inverter/leisure battery and the mains power supply, e.g. the 230 V sockets on the motorhome, boat or vehicle in general.