Be sure to buy the model for your job. 8 Terminals means switched 2-Wire, switched Positive-Neutral 110v. and used a separate common Ground bus. (Grid/OFF/INVERTER) I wired it for 2 power sources in/ 1 out. Used for switching RV Shore power to Inverter power. Switched two circuits of 5. Inverter on/off button and switch mounted right next to each other. 1500 watt sine wave inverter provides power to everything but AC and Frig(ac/dc/propane) and battery charger. Don't do this unless you are an Electrician or know a good one. -----In process of doing this in the House too, to switch a new 30 amp Sub-Panel Breaker box from Grid to Inverter. 30-amp box will feed lights, tv, internet, frig, microwave, coffee maker etc. Inverter is out in the shed next to solar panels/ batteries and generator.