New to Solar. Looking for advice

[diybodger]

Hi, I have been given 2 x 225w Canadian Solar panels and a 120ah Leisure battery. I would like to use them on my shed to charge my cordless batteries. But as I read about Solar on the internet, have become quite confused as to what ratings would be needed and an issue I think I have.
Firstly, I purchased a cheap MPPT controller off ebay and just rigged the panels up to see if it worked. They did but when it got dark the battery drained. I have read that this could be due to the diodes on the panels are no longer working. Is there a way to test this?
Secondly, I am thinking I need a 60A controller. Is this correct?
Thirdly, would a 15A panel isolator be sufficient?
Finally, what rated inverter would I need to power 3 x 18v cordless battery chargers off a 120ah lead acid battery?

Lots of questions but hoping I can get some good advice so can move forward or at least, prevent burning down my shed!!!
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[chrisski]

You can read any sticky by SUNKING to get great starting info.

You can also go to DIYSOLARFORUM . COM to get more respon see.


Firstly, I purchased a cheap MPPT controller off ebay and just rigged the panels up to see if it worked. They did but when it got dark the battery drained. I have read that this could be due to the diodes on the panels are no longer working. Is there a way to test this?

I would start by disconnecting the panels after they charge and see if the same thing happens. I suspect a weak battery. If its that weak the battery wil drain without the panels.Can you check the diode with a multimeter? Short in one direction; open in the other.


Secondly, I am thinking I need a 60A controller. Is this correct?

Need to know more about the battery charger. For my usage with M18 Milwaukee rechargeable batteries with a single charging port, 140 watts of power is plenty, and I carge so infrequently, a 10 amp MPPT would be sufficient.


Thirdly, would a 15A panel isolator be sufficient?

I’m unfamiliar with a panel isolator.


Finally, what rated inverter would I need to power 3 x 18v cordless battery chargers off a 120ah lead acid battery?

This is the key to the whole project. I recommend getting a kilawatt meter and get accurate data by plugging the charger into the wall to see how much power this thing pulls on 3 empty batteries

Looking for:
1) Max Watts
2). Total kWh for the day.

There’s a bit more math involved for the build.

[SunEagle]

Just to let you know most good MPPT controllers are not "cheap" and ebay is not always to best place to purchase chargers