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Step Down PV Current?

Philfr

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Mar 18, 2021
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I have four 100 W panels to be mounted on my RV. Because of the layout of the air conditioner one will likely most always be somewhat shaded. As a result I had planned to hook up the panels in parallel.
Open circuit is 22.3 VDC and 5.86A per panel. So that leaves me at 23.4A.
I was considering a Bluetti AC200max But now I see that its incoming PV current is limited to 15 A.
So is there any reasonable way to step up the voltage and step down the current of my PV output before it reaches the Bluetti?
 
The AC200MAX will only pull 15A max current (it limited itself) from panels even though the panels can supply current higher than 15A, the main thing you need to watch for is to not to exceed 145VDC Max PV input Voltage.
Over-panelling is one way to collect power through out the day and especially if you have cloudy day.
See Will's video on over-panelling AC200MAX:
 
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was considering a Bluetti AC200max But now I see that its incoming PV current is limited to 15 A.
If it were me I’d do a cost and space analysis and decide if the cost of the bluetti makes sense over a typical charge controller and batteries setup.
Bluetti -type equipment seems attractive because it looks simpler but most of the time you can get way more useful power out of a more typical component AIO or traditional separate components.

My opinion is you can surpass the bluetti power by a lot for the same expense. So stepping up the voltage other than merely series/parallel 2S2P to accommodate the bluetti doesn’t make sense to me.
Over-panelling is one way to collect power through out the day and especially if you have cloudy day.
Well in that case it makes more sense. But I’d still consider alternative approaches myself. That way you can select bluetti or traditional in an informed manner.
 
The AC200MAX will only pull 15A max current (it limited itself) from panels even though the panels can supply current higher than 15A, the main thing you need to watch for is to not to exceed 145VDC Max PV input Voltage.
Over-panelling is one way to collect power through out the day and especially if you have cloudy day.
See Will's video on over-panelling AC200MAX:
Thanks. Voltage would not be a problem. Shading is. Electrically P2S2 would work as would 4S. But the Bluetti 15A limits effectively cuts off 1 panel in a 4P setup.
 
If it were me I’d do a cost and space analysis and decide if the cost of the bluetti makes sense over a typical charge controller and batteries setup.
Bluetti -type equipment seems attractive because it looks simpler but most of the time you can get way more useful power out of a more typical component AIO or traditional separate components.

My opinion is you can surpass the bluetti power by a lot for the same expense. So stepping up the voltage other than merely series/parallel 2S2P to accommodate the bluetti doesn’t make sense to me.

Well in that case it makes more sense. But I’d still consider alternative approaches myself. That way you can select bluetti or traditional in an informed manner.
Thanks. Voltage would not be a problem. Shading is. Electrically P2S2 would work as would 4S. But the Bluetti 15A limits effectively cuts off 1 panel in a 4P setup. The cost benefit is that I can pull the unit out of the RV when not in use and use it elsewhere. Other than that it would be cheaper to go the permanent component route.
 
Remember that with your panels mounted flat on the roof of an RV they're almost never going to put out full power. Most days you'll be lucky to see 70-80 percent, so. you really won't be overpaneled except for possibly a few days in the middle of the summer with the sun straight overhead. My camper's pop top tilts and by parking facing north and lifting the top so the panels face south I get at least 50 percent more power most of the time.
 
Remember that with your panels mounted flat on the roof of an RV they're almost never going to put out full power. Most days you'll be lucky to see 70-80 percent, so. you really won't be overpaneled except for possibly a few days in the middle of the summer with the sun straight overhead. My camper's pop top tilts and by parking facing north and lifting the top so the panels face south I get at least 50 percent more power most of the time.
True for the day to day - but from a safety standpoint the owners manual doesn't say what happens if 23A open circuit current hits the 200Max. Any ideas about that?
 
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