There are many reasons to leave an inverter on. The following applies to those in residential homes and also RVs, vans and other motorhomes. These are especially useful advice for inverters 1500 watts and larger. While there are many reasons to keep an inverter open, there are times when turning it off is ideal. The following applies mostly to RV inverters unless otherwise specified. Inverter technology has improved significantly and can run continuously without affecting performance. Of course you should always look in your owner's manual for. High powered inverters are meant to run continuously. Think of the modem connected to your computer. You don't turn it off when you sleep do you? High powered inverters have been built to run 24/7. As long as you use the inverter correctly there.