Originally posted by PNPmacnab
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Backpacking PV: looking for MPPT with energy buffer build-in?
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I'm sure you have seen this before. The buck or boost is faked into thinking the output voltage is too high and pulls back. The TL431 can even be replaced with an old power FET if you can accept a little temp drift. The 431 can only saturate to about 2V and you really shouldn't use it below 2.5V. The diodes and LED provide an offset voltage. At least one diode must be used in any circuit to prevent pulling down the sense voltage divider. .Many one chip buck modules with an inhibit/shutdown pin. That pin can be lifted up from the board common and with a pull down resistor can be used to turn the regulator on and off. These pins are quite fast. Any simple comparator circuit can be used. Use a couple diodes for a reference and you will have temperature tracking.Attached FilesComment
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MPPC (constant) is a fixed panel voltage. It can be made to track with temperature.
For those interested in the various methods used with solar panels this is pretty good. Teaching methods haven't improved in 40 years.Last edited by PNPmacnab; 07-15-2019, 12:13 PM.Comment
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Hello,
(the PV output voltage) it varies just a little. Temperature changes output voltage slightly
Choose a panel or a range of panels. Decide if you want the PV voltage to be higher than or lower than the battery voltage. Choose a controller accordingly.
This is not about your opinions.
It is about to get a device that does the job I want.
@Mod: Can someone regulate this stuff?
Since 2 pages this thread gets spammed with stuff not belonging here.
I have to laugh any time I see these MPPT schematics. It isn't only ebay that plays with the truth. That first link is to a MPPC controller.
Sad your response is only focusing for one link, because if seems like you are good with electronics?
So, if you would have read all the rest -and maybe stumbled across stuff like the LTC3870, or my spec list I look for - maybe you would be up saying something like "hey kid, I can help you creating some layout for a device you are looking for"?
I consider even paying for it so I get rid of this "proposed solutions" that do not fulfill the spec sheet.
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Originally posted by letmefreak View Post......
This is not about your opinions.
It is about to get a device that does the job I want.
@Mod: Can someone regulate this stuff?......
Powerfab top of pole PV mount (2) | Listeroid 6/1 w/st5 gen head | XW6048 inverter/chgr | Iota 48V/15A charger | Morningstar 60A MPPT | 48V, 800A NiFe Battery (in series)| 15, Evergreen 205w "12V" PV array on pole | Midnight ePanel | Grundfos 10 SO5-9 with 3 wire Franklin Electric motor (1/2hp 240V 1ph ) on a timer for 3 hr noontime run - Runs off PV ||
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-ListerComment
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