I have a Samlex 600 watt true sine wave inverter. Last night it switched to overload and I've not been able to figure out the problem. There was no overload on it at the time. I have been running a cordless phone for two weeks. It has a digital answering system and doesn't take a whole lot of power. If anything that small continuous load may be the cause. Yesterday I ran my 4 cup coffeemaker to brew in the morning. It uses all 600 watts of power from the inverter for the brewing cycle then I turn it off. Hasn't shown any problems before. Then I used my laptop on and off throughout the day. And egads (!) I listened to Beethoven's 9th symphoney over and over for about an hour :angel: But it was fine without any problems during the day. Sometime at night I heard the alarm and it switched off and lit the overload light. This morning I checked the cables and changed the 100 watt fuse on the positive cable. The charge controller is fine. Just the inverter. Any advice on what to look for?