How to Reset Solar Charge Controllers Step by Step

Solar controllers or charge controllers perform several important functions, mainly prevent batteries from being overloaded by current from a solar panel. Problems and glitches do happen though, but often a reset will fix it. This is how you do a soft and hard reset for PWM and MPPT charge controllers.

To perform a soft reset, press the reset and power buttons together for a few seconds and wait for the solar controller screen to flash and reboot. To do a hard reset, disconnect the solar panel and battery wires and wait a few minutes before reconnecting the wires.

How to Soft Reset Solar Controllers

If your solar panel has no voltage or not working properly, there might be a problem with your charge controller. Now is a good time to do a soft reset. Because there are many different types of solar controllers, the process may vary slightly with your own. Check your operating manual for details.

1. Hold the charge controller in your hand.
2. Press the reset button. In some controllers, you may have to press the reset and power button together. And in other models, you have to press four buttons.
3. Press and hold for a few seconds. Release the buttons and the controller screen will blink and flash. After a few seconds the regular display will appear.

A soft reset is similar to rebooting a computer or mobile device. It is the first step to take if the controller suddenly stops working. And usually this gets the job done.

However there may be times when a charge controller soft reset is not enough. In that case you have to do a hard reset.

How to Hard Reset Solar Controllers

A hard reset means disconnecting the hardware from the main system. In this case, you have to disconnect the charge controller from the solar panel. This is how it is usually done for all controllers.

1. You should do a hard reset at night. If you have to do this in the day, put a solar panel cover on the modules.
2. Turn the controller over. You will see four wires. Two are the positive and negative battery wires, and the other two are the positive and negative terminals for the solar panel.
3. Disconnect all four wires. Disconnect the batteries first, followed by the solar panels. Mark each one so you will remember where each goes later.
4. Wait a few minutes. Depending on the controller, this can be 2 minutes or 15 minutes. If it is a small glitch on the system, waiting a couple of minutes is fine. However it is best to wait longer.
5. Reconnect all the wires in the same manner you disconnected them.
6. Once all the wiring is in place, the charge controller will restart, similar to a soft reset.

That is basically all there is to doing a hard reset. As long as you rewire the connectors in the right place, there should be no issues.

How to Reset an MPPT Charge Controller

The steps above are for PWM charge controllers like the Renogy Adventurer 30A, as they are the most widely used today. However, MPPT controllers are gaining in popularity But how do you reset these systems? Is it any different from a PWM?

Rebooting an MPPT charge controller is no different from that of a PWM. For a soft reset, press the power/reset buttons (the number of buttons to press and hold may vary) and hold for a few seconds until the display restarts.

To perform a hard reset, repeat the steps given earlier. Disconnect the wires for the batteries and PV modules. Do not forget to cover the panels if it is daytime before removing the wire connectors.

When Should You Reset Solar Controllers?

Charge controllers should only be reset if there is a problem in the solar panel. Some like to reset the controller every once in a while to refresh the system. However it is not necessary, at least in newer models.

The only time you should be rebooting it is if the solar panel or battery is not running properly. There are many sorts of problems that can arise with solar panels and batteries. Charge controllers are the most sensitive component of the system along with the inverter, so you should look there first.

If your solar array is not working or the battery is not charging, try restarting the controller. In many cases it will resolve the issue. The best analogy is a laptop because charge controllers are also computers.

Sometimes a laptop will just freeze and it could be due to a program or the operating system. When that happens you reboot the computer and usually the laptop runs fine again. The same thing happens with mobile phones, tablets and yes, charge controllers.

In most situations this is all you need to do. However if that does not resolve the problem you have to do a hard reset. Because it is more involved you should only attempt it if a simple reboot does not work.

Should You Do a Hard or Soft Reset?

If there is an issue with your solar panel system, try resetting the controller. It might be a simple bug that can be fixed with a quick reboot, saving time and a call to tech support.

Always try a soft reset before a hard one. If you have a charge controller connected to a battery and it suddenly stops running, it could be the equivalent of a computer crash.

Try the hard reset option if the above steps do not fix the problem. Again, make sure all the wires are disconnected. Cover the solar panels or better yet, do this at night. If your system has an inverter, disconnect its wires as well.

If you are going to do a hard reset, take all necessary precautions. Solar panel systems are safe, but taking all the safety steps is necessary . If you are not comfortable tinkering with wires and cables, consult a professional solar installer.

What Solar Controller Problems Can a Reset Fix?

A lot of common problems can be remedied by a soft or hard restart. You do not need to know all the technical stuff why it works. But ask anyone who has used a solar controller before and they will tell you that rebooting or resetting is an effective tool.

Some of the issues that you may be able to fix are the following.

Moon error symbol. This usually appears on the display when the controller cannot detect any voltage from the solar panels. The usual fix – and often the most effective – is to do a hard reset. Disconnect the cable and use a multimeter to check the panels status. Then reconnect the wires and everything should run normally.

Controller displays 0.0 amps charge. There are many possible reasons for this error message. These include a blown fuse, poor wring from the panel to the battery, a full charge in the battery or the panels are dirty.

Check first if the battery is already full. If it is the display will show 0.0 or close to it. If not, look at the solar panels and if they need to be cleaned If that does not remedy the problem, do a soft reset and then a hard one.

Display freeze. Someti8mes the numbers on the controller screen will just freeze. If that happens, a quick restart should restore everything to normal. If that does not work, disconnect the battery and solar wires as described above.

Charge controller loses power. If your controller suddenly loses power, check the MC4 connector. It might b loose or frayed. Replace it immediately and reset the system. In this situation you have to perform a hard reset since the wires have been replaced.

Blinking lights. This could be a sign of a faulty controller, but it could also be a minor glitch. Remove all the wires but wait for 15 minutes minimum. Reconnect the cables and try it again. Usually that takes care of the problem. If not, there might be other issues with the controller and it needs to be repaired or replaced.

Conclusion

Solar controllers are integral to any PV module setup, and they must be working properly for your system to generate power. Knowing the difference between hard and soft resets and how to do them are paramount in keeping a solar array working.