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Jaycar-Electronics / Solar-MPPT-Charge-Controller

Use a Nano to control the flow of energy from a Solar panel to a battery!
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Values of R1, R3, R4 missing #6

Open au-chrismor opened 3 years ago

au-chrismor commented 3 years ago

The schematic shows these components without values. Parts list shows 1M, 10K and 91K resistors (1 pack each), but there is no association between them. Presumably 2x10K in parallel makes up R5 since there's no suitable entry in the parts list.

Luban666 commented 2 years ago

same

mjolnir71 commented 2 years ago

Seems like someone stopped working on this before it was finished. Seems like R1 should probably be 10K, R3 and R4 should be providing the A/D input with whatever voltage the software expects, which will have to be between 0 and 5 volts, I would have designed for about 2.5V with the battery at about 12, but I haven't got that far into the code yet. The code is also very incomplete, it does not display any actual numbers on the LCD, and the rotary encoder is not implemented. John

Luban666 commented 2 years ago

I did similar things and yeah, the 10k still to high since we only need a voltage 1M may more suitable

mjolnir71 commented 2 years ago

The way I see it, when the BC547 pulls low the capacitor will charge via the diode, so the gate of Q1 will quickly turn off. But when the collector of the transistor goes high R1 (10k?) will hold one end of it at the potential of the positive line. The other end will now be higher, by the amount that it was charged by, and will turn on the MOSFET. That charge will tend to leak away via the circuit R1 and R2, but R2 is 1 MOhm, giving a reasonable time constant before leakage would turn the gate off again. So R1 doesn't need to be an especially high value, but of course should not be too low. Anyway, having just got my mistakes corrected enough that I was seeing drive to the gate, something managed to touch that shouldn't have, so now I have put it aside until I get a new Arduino. I have a few others, but they are in projects that I don't want to disturb. (I'm using a pro mini clone, which changes the layout of that part, but is otherwise the same.) regards John

au-chrismor commented 2 years ago

Now that things have settled down for me, I am going to go back and revisit this one.

Agreed with the comments for component values, and I would like to at least get the display to show something meaningful. It looks to me like the version of software which was photographed for the article is not the same as the version on here. But that shouldn't stop us from figuring it out.