Can you just check the output with a meter ?

Yes you can

thanks

You can get a cheap volt meter from Harbor Freight, Home Depot. Put it on 20V. Connect to end of solar in direct sun. It must read greater than or equal to the volt rating of the solar for it to still be putting out proper power.

Great Info

Thanks

The above information is not correct. It can be putting out the proper voltage, but still be bad. The milli Amperes output will determine whether or not it is working properly. Below is a copy/pasted explanation from "ranchdog" on another site:

The pic below and is how you test a solar panel and what a Good solar panel test like (amperage not voltage)

First make sure your meter measures DC mA (Direct Current milli Amperes) usually they go up to 400 ma on one switch setting and 1.0 A on another setting. So make sure your on the correct mA setting on your meter. In this photo the meter is set on mA (max for my meter is 200 mA). A solar panel like we use on our feeders usually max out around 60-70mA but check your panel.

So hook the meter up in Series (inline as shown below) You will need a good battery, not a completely dead one that won't take a charge. So you can see that the solar panel is putting out 69.2 mA. The voltage was 18 Volts I measured but don't show here but will below on the bad one. But as you will see in the next set of pictures / description what a bad solar panel looks like.



Now what a bad solar panel looks like.

In the picture below I simply measure the voltage and I get 17.69 volts. So you would think it is working. HOWERVER, in the second picture where I measure the current notice that it is not putting out but 0.6 mA. It is bad and will not charge your battery. It should be putting out around 60-70 mA.



Here is the 0.6 mA. This is not working and is a bad solar panel. Throw it in the trash. You should be getting around 60 mA in FULL SUN. On a cloudy day it might drop down or if your battery is really charged. This test was done at the same time as the good solar panel in the above posting less the 1 minute apart so the sun was basically the same intensity.



Source: http://discussions.texasbowhunter.com/forums/showthread.php?t=655305&highlight=solar+panel+test

ckat is wise...


I will add that a quick go-no go test for a panel is to disconnect one lead between the panel and the battery. Press the test button on the feeder timer and make sure it spins at full speed. If the feeder will not spin at full speed, then charge the battery before proceeding. After the feeder runs, let the battery rest a couple of minutes, then check the battery voltage. With the volt meter still connected, attach the solar panel lead. You should see the voltage on the battery increase at least a couple of tenths of a volt, maybe a couple of volts, depending on how well charged the battery is. If you do not see this increase, your panel or wiring is bad.


Batteries tend to go bad more often than solar panels.
If you do not have a charge regulator, then replace your battery every year.
If you do have a charge regulator, then replace your battery every three years.
Your battery capacity (regardless of age) decreased a lot as the temp falls, but you solar panel output increases a little in cold weather. If your feeder dies in cold weather, but not in warmer weather, don't blame your solar panel.
Charging batteries in the heat kills them quickly. Charge regulators help guard against this. They also prevent over charging.

A panel with a dirty surface is not going to produce much power. A panel with plastic (as opposed to glass) over the cells needs to be replaced when the plastic starts to turn cloudy and yellow.
I hate the panels with the textured lens surface...this tends to hold dust and raccoon po.

Angle and direction are VERY important. Trees are bad!

Thanks Folks just started using solar panel on my feeders this is the first one to have a issue . Learning as mush as I can to maintain my feeders

Thanks again

Great info "ckat", I will have to file this thread away for future reference.

I learned something here as well! I agree with Nak. Typically the battery most of the time. Before buying a volt meter I use to take my old battery to Batteries Plus, get it tested and swap it out if bad. Then check the battery level indicator on the timer a few weeks or a month later and if it continued to drop, that would indicate a bad solar not charging the battery. Process of elimination works sometimes as well. On new solar panels, I now apply a little caulk to the top and sides to prevent water from getting in. I think they are lasting longer for me than before. I have had mold grow on the inside of the ones from Academy less than 1 year later, especially in shaded areas.

ckat's method is sound. You have to put the panel under load.