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100/50 MPPT Very Low Amps


I have the 100/50 solar controller. I have one suitcase solar panel. I believe it's rated for 120w. I wired it in series. VictronConnect app (VCA) is telling me (pretty consistently): 40v-47v going into the controller; max 4w and about .3a at most going into the controller (located in AZ). The 12v batteries are showing about 13.5v-13.8v. So they appear to be full and in good working order. I'm running 8ga wire (~60')

1. is the reason i'm getting such low amps (other than series wiring) due to the batteries being full?

2. i would think the solar panels are sending a good amount of power to the controller. and the controller would know the batteries are full and not pass the power onto the batteries. but if #1 is correct, then should I assume the controller doesn't do this? ie, if batteries are full, current drops way down even betw the controller and solar panel (as opposed to getting a lot more current betw the panel and the controller, but very little of it is passed through the controller to the batteries because they're full)

3. would i be better off going back to parallel wiring?

4. last, how would I know if the controller was bad?


any suggestions? much thanks from a solar rookie!

MPPT Controllers
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psea avatar image psea commented ·

@klim8skeptic

it is definitely in the float stage. i understand this affects how much more power can be crammed into a full battery. but what I'm trying to understand is if the batteries are full, does that also affect how much solar power is coming into the solar charger? thanks

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klim8skeptic avatar image klim8skeptic ♦ psea commented ·

" does that also affect how much solar power is coming into the solar charger"

Yes, there is no where for the power to go.

Now if you were to turn some loads on, you will see the power ramp up.

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klim8skeptic answered ·

I would think that the battery is fully charged, and the mppt has switched to float.

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