How to Test Solar Panels

When you take a leap into the world of solar energy and buy your first set of panels, it’s critical to know how to test solar panels. Once you install the solar panels, the next step should always be to test the solar panels in order to make sure you’re getting the power you’ll need.

Most people overlook this step despite its significance. Moreover, the only way to know for sure if you’ve bought high-quality panels is via solar panel testing.

Therefore, in this guide, we’ll closely look into how to test solar panels to ensure you have the best possible experience.

How to Test Solar Panels


Before you start testing solar panels, here are some of the things that you must know:

How a solar panel system works – In simplest terms, the electric current has two classifications:

  • Alternating current (AC)
  • Direct current (DC)

Direct current flows only in a single direction and is typically used for low voltage requirements, like with solar panels. Moreover, you’d most likely have to measure the output in watts as most household appliances gauge power use in watts. For testing solar panels, there’s a particular formula that you’ll have to use. The formula is:

Wattage = Voltage

To measure a solar panel system’s total power generation capacity as well as to see whether it’s enough for your needs, you’ll also have to calculate the voltage and wattage.

Measure the solar panel amperage – To do so, you’ll need a solar panel tester called an “Amp Meter.”

In order to gauge the amp production of your solar panels, you’ll have to connect the amp meter to the positive and negative. Remember, you’ll need an amp meter that measures greater than the amp production of your solar panels to get an accurate measurement.


Tip: To get accurate results, ensure that your solar panel is in full sunlight when tested. 

Measure current with multimeter and resister – Use both types of equipment to measure DV voltage. Once done, the new formula will be current = voltage.

Once all this is out of the day, it’s time to get your hands working.


  • Multimeter
  • Resisters
  • Solar panel tester (amp meter)
  • Alligator clips
  • Ample sunlight


First and foremost, in order to accurately test solar panels, it’s crucial that you know how to correctly use a multimeter. In case you don’t, there’s a high possibility of permanently damaging the panels. Here are four easy steps to help ensure you do an immaculate job:

Step #1: Find the Converter Box

The first step in solar panel testing is to locate the converter box. Typically, it’s present on the backside of a solar panel. Once it’s found, the next step is to uncover the box so that you can easily view the connections inside.

Step #2: Note +ive and –ve Connections

Keep in mind that this is a very critical step in testing solar panels. So, once you’ve noted the positive as well as the negative connections, ensure that your solar panel is in full sunlight. For this, you may have to tilt the panel a bit to make sure it’s optimally exposed to the sun.

Step #3: Set the Multimeter to Direct Current (DC)

Next, make sure that you measure at a level that’s greater than the volts the panel has been rated for. For instance, if the solar panel is rated for thirty volts, you should set the multimeter to read higher figures. Doing this helps in ensuring that you get accurate results. In order to know your solar panel’s voltage rating, you’ll have to check the insides of the converter box where it’s usually marked.

Step #4: Connect Alligator Clips Suitably

For the next step, you’ll have to attach the red wire of the alligator clip to the +ive side and the black alligator clip to the –ive side. Once done, your multimeter should display an accurate volt reading that’s produced by a solar panel. If your solar panel is new, keep in mind that it should generate voltage closer to what it has been rated for. On the other hand, if the solar panel you’re testing is old, the reading can possibly be a bit lower.

Caution: Before detaching the alligator clips, be sure to turn the multimeter off!

Please note that generally, solar panels are 12 volts. Nonetheless, the testing method is basically the same. Just make sure that you attach the +ive to +ive and -ive to -ive when connecting the multimeter to the connections existing at the backside of your solar panels.

In case you’re testing a 12 volts solar panel, set the multimeter higher than 200 VCD to make sure you receive the most accurate reading. If the multimeter prompts an overload, it’s a clue that you’ve set the VCD too low, and hence, it needs to be turned up. Moreover, as long as your meter is working fittingly, you would receive accurate solar panel readings. However, bear in mind not all multimeters are created equal. You can find numerous types of multimeters in the market that vary both in quality as well as price.

Our Final Thoughts

Now that you’ve installed and tested the solar panels, we hope you leverage the many benefits solar energy can offer. The most important being a reduced carbon footprint and an evident slump in energy bills.

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