How to Test Solar Panels

How To Test a Solar Panel: A Complete Guide & Tutorial

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Testing solar panels are important before you achieve commercial operation date (COD). You must demonstrate that your solar project is ready to operate. Here is a full guide on how to test a solar panel, including a tutorial and instructions.

How To Test a Solar Panel: A Complete Guide & Tutorial

When you make the leap into solar it is important to know how to test a solar panel. Once you install your solar panels, you’ll want to check the output to ensure you are getting the power you’ll need.

It is almost certain that you’ll need more than one solar panel but it is important to know how many you’ll need.

This how-to guide for testing solar panels is a good start. This will help once you buy your first solar panel.

Where to Begin with Testing Solar Panels

Here are some steps on how to begin testing solar panels. First, let’s talk about everything you need to know about solar panel systems and how they work.

1. What You Need to Know About Solar Panel Systems

There are two classifications for electrical current, AC and DC. Alternating current is classified as AC and direct current is classified as DC. Due to the fact that DC, direct current only flows in one direction and is used for low voltage needs, such as with the solar panel.

It is almost certain that you need to measure the output in watts since most household appliances measure power usage this way. There is a specific calculation that you will need to use for your solar panel tests.

Wattage is power and equals voltage which is the current. To make it simple, remember that wattage = voltage.

To calculate a solar panel system’s power production and determine if it is sufficient for your needs, you will need to measure the wattage and voltage.

2. To Begin Measure Solar Panel Amperage

You will need a solar panel tester known as an amp meter. To measure the amp output of your solar panel you will need to attach the meter to the positive and negative. To get an accurate measurement, you will need to ensure that your panel is in full sunlight when you test.

Keep in mind that you will need an amp meter that will measure higher than the amp output of your solar panel to get an accurate measurement.

See Related: Should You Buy or Lease Your Solar Panels?

3. The Next Step is to Measure Current

The correct equipment for this next step includes resisters and a multimeter, which you will need to measure DV voltage. After this measurement, the correct formula will be the current equals the voltage.

Using a Multimeter for Solar Panel Tests

When testing solar panels it is essential that you know how to properly use a multimeter. If you use a multimeter inappropriately, you could possibly damage your panels.

Additionally, the only way to know if you have purchased high-quality panels is through solar panel testing.

Step 1. Locate the converter box.

The converter box is located on the back of the solar panel. Once you have located the converter box, you will then need to remove the cover. When the cover has been removed, you will then be able to see the connections inside.

Step 2. Note Positive & Negative Connections

It is important that you take note of the positive connection and the negative connection. Once you have noted which connections are positive and negative, you’ll need to make sure that your panel is in full sunlight.

To do this you will need to tilt the panel so that it is exposed to as much sunlight as possible.

See Related: Best Solar Installation Jobs

Step 2. Set Multimeter to DC

Check to ensure that you are measuring at a level that is higher than the volts the solar panel is rated for. For example, if your panel is rated for 20 volts, your multimeter will need to be set to read higher.

By doing this, you can be confident that you will get an accurate reading. To find out what your panel’s voltage rating is you will need to check inside the converter box where it is typically marked.

See Related: How Solar Panels Work in Weather Conditions

Step 3. Connect Alligator Clips

You will need to connect the red lead from your alligator clips to the positive side. Once this is done, connect the black lead to the negative. When you have completed this step, your meter should give you an accurate reading of volts that are produced by your panel.

New solar panels should produce a voltage that is close to what it has been rated for. If you’re the solar panel you are testing is used, you may receive a lower reading.

This is not unusual. Before disconnecting the alligator clips, ensure the multimeter has been turned off.

Testing the 12 Volt Solar Panel

How to test a 12-volt solar panel vs other voltages?  As most solar panels are 12 volts, the solar panel test methods are basically the same. You will want to ensure that you place the positive-to-positive and negative-to-negative when attaching your multimeter to the connection on the back of your solar panel.

Set the meter to above 200 VCD to ensure you get the most accurate reading possible. If your meter indicates an overload, you have the VCD set too low and it will be necessary to turn it up.

As long as your multimeter is working correctly, you should get an accurate reading on your solar panel. Keep in mind that not all meters are created equally. There are a number of different multimeters and they tend to vary in price as well as quality.

See Related: How to Clean Your Solar Panels Safely

Testing the Charge Controller

When testing solar panels you should also test the controller. This is important in the case of solar plus storage. You can do this with a few easy steps.

  1. Set the meter to measure DC Amps and make sure that the leads are in the right port to measure DC Amps.
  2. Next, set the meter to ~10A.
  3. You will next connect the solar panel to the controller as well as the controller to the battery.
  4. The next step in the process is to disconnect the positive cable that runs from the battery to the controller.
  5. To measure the current you will need to connect the positive lead from the meter to the positive cable
  6. Once this has been done, connect the negative lead from the meter to the positive terminal on the battery.

This test will measure the current passing between the panel and controller and to the battery.

If you need a battery, check out these best batteries for solar panels.

Conclusion on How to Test Solar Panels

Testing your solar panels is a crucial step in the process of going completely off the grid. You will need to know how the solar panels perform in their desired installed location before you turn on and begin producing power.

This will help you optimize performance and get the most out of your solar panel production. You will want the highest capacity factor that you can achieve to ensure that you get the best bang for your buck with your solar installation.

Are you ready to start testing your solar panels? Let us know in the comments below.

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