How to test a feeder solar panel ?

[ranchdog]

I have the solar panel listed below on my feeder. I put my digital meter on it in amperage mode in full sun and I only got 5.30 mA DC using the milli Amp setting on my meter. I thought it was bad since I thought they put out 60mA in full sun. Now at home I am getting 19 volts but still the 5.30 mA.

When I tested the new one at the lease that I put on and I again am only getting about 5.50 mA per my meter. I am wondering if my meter is bad or what. My testing is in full sun and letting it sit for a while.

Any ideas what I might be doing wrong? I should be getting like 60mA per the specs.

If you have a solar panel and meter handy could some of you test yours for Voltage and milli Amps. I thought you had to measure amperage under load but I don't think you do with this meter as it has a built in resistor that must act as the load.

Is it safe to assume that it is working correctly if your getting a full voltage like 12-18 Volts?

Thanks, Ranchdog



Description

Item No.: 684-SP60-12V

Product Name: 1.26 Watt, 60mA and 18 Volt
With built-in blocking diode to prevent reverse flow of electricity

Maintenance-free solar power gives years of use at no cost
Stand and wire with clips are provided for charging batteries
Ideal for use in marine yacht, sailing boat and other outdoor activities
Daytime charge and energy is stored for night-time use
For 6V or 12V rechargeable battery and uses
Power: 1.26W, 18V and 60mA
Size: 159 x 175 x 17mm
Lightweight of 0.365kg

[scotty]

I'm not sure how to test it, but I had one that registered putting out more than 12 volts that wouldn't keep a battery charged. I finally replaced the solar panel and my problems stopped.

[6.8mmSPC]

I would think that if your battery is charged up then the panel will put out less current. Remember you have to draw current with some sort of load.

[coop2564]

the panel can be bad even if it reads 12 or more volts.. to test amps u have to reconnect your leads to the amp ports on meter, then take your red positive wire off battery post, then connect one meter lead to battery post and the other lead to wire this completes the circuit it will then give you your current reading....how much output you get can be in correlation to how charged your battery is if its fully charged mine seems to always read less and when its not fully charged closer to rating.

[atombomb]

maybe you have the wrong setting on the meter and you're getting 53, not 5.3

[ranchdog]

maybe you have the wrong setting on the meter and you're getting 53, not 5.3

That is what I thought but I have it set on mA and the auto setting range. If I set it on uA (mirco Amps) I do get 53, but on mA I am getting 5.3mA

Just does not make sense. The meter should provide the constant resistance therefore, I=V/R. Since the meter has a known set resistance in it, it measures the voltage to obtain the Amperage (I)

That is why you can't over load the amp meter because it can only handle so much. I think some of the guys are correct that it can have the proper voltage but still not be working well, hence my measurement of the open circuit current.

RD

[ranchdog]

the panel can be bad even if it reads 12 or more volts.. to test amps u have to reconnect your leads to the amp ports on meter, then take your red positive wire off battery post, then connect one meter lead to battery post and the other lead to wire this completes the circuit it will then give you your current reading....how much output you get can be in correlation to how charged your battery is if its fully charged mine seems to always read less and when its not fully charged closer to rating.

I agree with your point. But the meter is supposed to simulate that same load by using an internal resistor with a small heat sink that simulates full load current draw no?

[scotty]

I've also had batteries that show 12volts plus that wouldn't spin a motor.

[ranchdog]

I've also had batteries that show 12volts plus that wouldn't spin a motor.

Yeah your right Scotty, that is why I wanted to test the solar panel to make sure the thing is working correctly. Sure there is a way to properly test the thing.

[6.8mmSPC]

I agree with your point. But the meter is supposed to simulate that same load by using an internal resistor with a small heat sink that simulates full load current draw no?

Your meter has to go "inline" with your panel to figure how much current your drawing. If you are hooking up the red on the solar to the red on the meter and the black on the solar to the black on your meter then I have no idea what you are measuring.

To measure what your battery draws while charging then you need to "break" the link between the solar and the battery and splice your meter into the circuit allowing the current to flow from the solar to the batter and then you can measure how much current you are drawing.

Try this article

http://scienceshareware.com/how-to-m...with-a-dmm.htm

[ranchdog]

Your meter has to go "inline" with your panel to figure how much current your drawing. If you are hooking up the red on the solar to the red on the meter and the black on the solar to the black on your meter then I have no idea what you are measuring.

To measure what your battery draws while charging then you need to "break" the link between the solar and the battery and splice your meter into the circuit allowing the current to flow from the solar to the batter and then you can measure how much current you are drawing.

Try this article

http://scienceshareware.com/how-to-m...with-a-dmm.htm

Ok, Your right, that is how I learned it too. But the manual is showing something different. However I went out and hooked it the way you suggested and on a fairly charged battery I got 0.72 mA, I then got an old uncharged battery and it said 2.34 mA.

I think the meter is wack. I think I am going to run to Lowes and get another one. But who knows. If anyone can do a test with their meter on a solar panel and battery to charge hooked up like 6.8mmSPC suggest then chime in with your readings.

Ranchdog

[6.8mmSPC]

Mine reads 30-40 mA in full sunlight

[ranchdog]

Well 6.8mmSPC,

It was the stinking Sears Craftsman meter . Man what a pain. I went to Lowes and got another meter and boom 44.6 mA right on the button . I re-hooked the Sears meter up again in series just the same as the new one and got a crappy 6.7 mA.

So I did learn a few things.

The one solar panel was bad. But it would give me 19 volts but no amps, I mean zero mA. I knew it was bad because it would not keep a good battery charged on the feeder. Hooked up another good solar panel that was working and got 18 volts but this time 44.6 amps. Checked several times just to confirm.

It does help to have a good battery as I tested it both with an old no good one and it gave me like 3 mA since I am assuming the battery would not take a charge. Put it back on a good battery and got the 44 mA again.

Yep, the new meter clearly explained that the meter must be hooked in series. The Sears Craftsman never mentioned "Series" just some crappy diagram that shows a Parallel hook up I swear best I can look at it anyway. But I had also hooked it in Series but of course since it was bad I did not get a good reading.

Anyway now I know how to test a Solar Panel. Hope this helps someone else.

Just because it is putting out voltage does not mean it is working. You need to hook it up in Series (inline) and use a good battery and you should get a good mA reading around 40 -60 mA in good sun . That is crazy .

Thanks for the help everyone.

Ranchdog

[6.8mmSPC]

Glad to help.

[Bowtech32]

Learned something new, I have alway's touched my tounge to it....