Bests & Worsts Reviews from Amazon

I see a few complaints in the reviews about having trouble with high-load applications of this inverter. I bought one about a year ago, with the intent of using it to get solar-powered air conditioning in my RV. I made it work, eventually, and the problems I encountered had nothing to do with the inverter (which supplied 1500 watts sustained load and handled the surge of starting the AC, once I got everything else working). First of all, wiring: Everything will tell you that 4 gauge should be more than big enough: Not even close. I tried 4-gauge. Then I tried 0-gauge. Then I tried making the wire runs shorter. Then I started doubling up wire runs in parallel. By the time I was through, my battery interconnects were double and triple 4-gauge in parallel, and the connection to the inverter (coming from the center battery of 5) was 000-gauge (also known as 3/0). Connecting that to the terminals on the inverter required taking an industrial terminal block normally used for substation wiring and drilling a 3/8" hole to connect it to the terminals. Finally I had something that wouldn't drop 2+ volts over the wires when drawing 125 amps. When they say 4 gauge can pass 200+ amps, they mean that it won't melt the wire, not that it will give you a usable voltage. On top of that, batteries: Lead-acid batteries may say they can deliver huge numbers of amps, but not without huge voltage drops. In practice, for every amp you're drawing you want at least 2 pounds of battery (so, minimum 4 size 27 batteries to deliver 125 amps needed for 1500 watts). Try to power your space heater off something you can pick up assisted, and you're just going to get a lot of annoying beeps. And don't forget that after you've drawn off half of the amp hours theoretically available in your batteries, your *maximum* voltage will have dropped to around 11.8 (so battery load and wiring losses will be working from a lower baseline). With 5 type 27's, I could run the original rooftop air conditioner for no more than 1.5 hours before they were too far down to provide 11.0 volts under load. So I figured out a way to mount a modern, high-efficiency unit that provided the same cooling for half the power. The point here is that with a really big inverter, you're pushing 12V right to the absolute limits, and you have all *kinds* of weak points that will keep your system from working properly. These are really intended for big residential solar systems with batteries in the thousand-plus pound range. This inverter works *fantastically* well, now that the rest of the system is properly supporting it, but even for an experienced electronics tech getting all that arranged properly was quite an education.