How to hook amp hour meter to solar panels before charge controller

bulrush

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I have the Harbor Freight Thunderbolt panels with charge controller and a 12v lead acid battery. I got this device to measure the amps, volts and amp hours coming in to the charge controller but I am still unsure how to wire it to my system, even after doing some Google searches for diagrams.

How would I wire this to my solar panels? Does anyone have a diagram to do this? The diagrams I have found are only to measure the power used outgoing from the battery, not incoming from the solar panels.
  1. This meter does not need a busbar.
  2. The panels put out 25w each at 18v, so max 1.39amps under perfect conditions.

Thanks!
 
Last edited:

HighTechLab

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Scroll down on the link you posted.

1570107893976.png

In this case replace the light bulb thing with the positive and negative of your solar panels

NOTE THAT THE RED WIRE OUT OF THIS METER WILL BE NEGATIVE AND THE BLUE WIRE SHOWN IN THE DIAGRAM GOING TO THE POSITIVE TERMINAL OF THE BATTERY IS YOUR POSITIVE.
 

Craig

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Scroll down on the link you posted.

View attachment 656

In this case replace the light bulb thing with the positive and negative of your solar panels

NOTE THAT THE RED WIRE OUT OF THIS METER WILL BE NEGATIVE AND THE BLUE WIRE SHOWN IN THE DIAGRAM GOING TO THE POSITIVE TERMINAL OF THE BATTERY IS YOUR POSITIVE.
Wouldnt you replace the battery with the panels and the light with the SCC or does it matter.
The panles are the energy in his system and the SCC is the load

Note to OP be careful you don't overload your meter it can only handle 10 amp those panels put out 8 so it should work but its close to the edge.
 

bulrush

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Note to OP be careful you don't overload your meter it can only handle 10 amp those panels put out 8 so it should work but its close to the edge.
The ammeter in my charge controller says the panels are only putting out 50ma at most. What I mean is, the built-in ammeter in my charge controller only shows one decimal point and rarely shows 0.1 amps coming from the panels even on the sunniest days. My panels are mounted indoors in a south facing window. Hence my want to double check this with another meter that has at least 2 decimal places for the amps.

Oh crap, is my window filtering out some of the sun's energy? Plus the angle is 90 degrees, which isn't great. Because when I took one outside it was putting out at least 500ma when I measured it with my multimeter.

I can't put my solar panels on my roof as that would void the 25 year roof warranty. And I have a very small lot and putting the panels on stands outside may not be allowed by the city and would likely cost 100s of dollars.

There are other considerations for me too, like the outside of my house is all cinder block so drilling through that to run wires from outside solar panels is a pain.
 

Craig

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I had same problem with Harbor Freight set up I got no juice in the wide open sunshine. I think it's because I bricked the SCC by hooking it up without the battery connected
 

bulrush

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I had same problem with Harbor Freight set up I got no juice in the wide open sunshine. I think it's because I bricked the SCC by hooking it up without the battery connected
The panels put out 25w each at 18v, so max 1.39amps under perfect conditions. I think that's my problem, they are crappy panels. Well, it was just a starter system that I could learn on. What a waste of $160. I would have been better off getting a single Renogy panel for $160. Today is a cloudy day so I'm not even measuring any microamps from these via my multimeter.
 

Craig

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The panels put out 25w each at 18v, so max 1.39amps under perfect conditions. I think that's my problem, they are crappy panels. Well, it was just a starter system that I could learn on. What a waste of $160. I would have been better off getting a single Renogy panel for $160. Today is a cloudy day so I'm not even measuring any microamps from these via my multimeter.
But that should be 1.39A x 4 you should get about 8 amps from the 4 in series.

Also save the 160 go to Craig's list and buy a 300watt panel for about 120
 
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