I ordered this inverter as part of a solar system I am installing in my shed. I tested it and everything was fine, booting fine etc until I was done and wanted to turn off the device. I flipped the switch but the device didn't respond and continued to work under load. Unplugged, tried, same thing. Finally I disconnected the load and clamps, turned off the power and reconnected the clamps. At this point, the switch was functioning normally, turning the device off and on with and without a load. I left it on overnight and tried turning it off again in the morning and the same thing happened. The inability to turn off the device with the power button is an obvious security issue (not to mention it makes me wonder what else could be wrong that I haven't seen). For this reason I am going back and looking for another inverter.