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kdrozda avatar image
kdrozda asked

MPPT 100/20 FUSE

Hi everyone. I have SmartSolar MPPT 100/20. And I have two questions: should I put a fuse between the controller and the battery? I know that there is already a 25A fuse in the device, but I do not know which line is protected by PV - MPPT or MPPT - BATTERY or maybe both or just LOAD? And second, is it true that if I disconnect the battery with solar panels connected, I will damage the charge controller? Regards Chris

MPPT SmartSolar
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1 Answer
seb71 avatar image
seb71 answered ·
should I put a fuse between the controller and the battery?

Yes. Size it to protect the wire.

is it true that if I disconnect the battery with solar panels connected, I will damage the charge controller?

You should avoid doing this. The charger might be damaged (so this "might be damaged" means that it can also might be fine).

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kdrozda avatar image kdrozda commented ·

Thanks for the answer, can you tell me what fuse value ... 30A?

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seb71 avatar image seb71 kdrozda commented ·

What wire size (cross section) you will use betwen the battery and the MPPT charger?

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kdrozda avatar image kdrozda seb71 commented ·

6mm2

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seb71 avatar image seb71 kdrozda commented ·

That's the maximum it can take, right?

And I assume it's copper.

Use a 25A fuse.

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kdrozda avatar image kdrozda seb71 commented ·

6mm2 - yes it is max.
The last question, maybe stupid - if the battery also receives electricity from the alternator (of course, through the starter battery and the cyrix 120A), it will not damage the MPPT connected to the battery? Cyrix has a 120A fuse, should I somehow separate the charging system and disconnect the solar system while the engine is running?


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