MPPT solar charge controller recommendation?
So I've got some cash now to put into my new to me Lance, and I've decided to build my own 200watt system from scratch rather than purchase an all inclusive kit. I'm going to use cross bar roof rack i...
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MPPT is absolutely the way to go, and I also have done 3 installations so far with the Morning Star 45amp MPPT Controller. And on all 3 systems I used the wired status panel remote.
On two of the systems I wired 4 panels in series-parallel for a 92v OCV (Open Circuit Voltage), the 3rd system just straight parallel for a 46v OCV input. The controller handles up to 150v OCV. The advantage to higher input voltages is less loss due to wiring, and you can use smaller gauge wiring from the panels to the controller.
The other advantage I've noticed, the 92v OCV systems combined with the MPPT work to create 12v charge at lower light levels because the OCV only needs to go above 12v - so if your peak is 92v, I literally can get them to work off my garage shop lights. The 46v system is not quite as efficient. The lower your solar's OCV, the more light you will need to cross that 12v threshold and actually start charging. Ideally on my controller, I should be running 3 in series @ 138v for the best efficiency, but I don't have room for 6 panels.
The morning star controllers are easy to set up, quick to react and recover from clouds/shade, and have worked flawlessly so far.
The panels I'm using have a short-circuit output (in real life as measured by my meter) a little more than 4 amps each, and with 4 of them via the MPPT, I've been seeing 12v amperage around 35a, constant.
On two of the systems I wired 4 panels in series-parallel for a 92v OCV (Open Circuit Voltage), the 3rd system just straight parallel for a 46v OCV input. The controller handles up to 150v OCV. The advantage to higher input voltages is less loss due to wiring, and you can use smaller gauge wiring from the panels to the controller.
The other advantage I've noticed, the 92v OCV systems combined with the MPPT work to create 12v charge at lower light levels because the OCV only needs to go above 12v - so if your peak is 92v, I literally can get them to work off my garage shop lights. The 46v system is not quite as efficient. The lower your solar's OCV, the more light you will need to cross that 12v threshold and actually start charging. Ideally on my controller, I should be running 3 in series @ 138v for the best efficiency, but I don't have room for 6 panels.
The morning star controllers are easy to set up, quick to react and recover from clouds/shade, and have worked flawlessly so far.
The panels I'm using have a short-circuit output (in real life as measured by my meter) a little more than 4 amps each, and with 4 of them via the MPPT, I've been seeing 12v amperage around 35a, constant.
