Solar charge controllers regulate the amount of charge that flows to solar batteries in solar systems with battery back-up options or off-grid systems. They’re a useful safety mechanism that ensures solar battery systems run efficiently — but what does it mean for your system when your solar charge controller is on the fritz? And what can you do to fix it?
We’ve listed some troubleshooting tips for solar panel charge controllers below, as well as a general guide on how to reset your solar charge controller should you need to.
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What is a solar charge controller?
Solar charge controllers regulate the power flow between solar panels and a battery. They prevent the battery from overcharging during the day and stop power flowing back to the solar panels at night when they’re not producing voltage.
There are two types of solar charge controllers: Pulse Width Modulation (PWM) and Maximum Power Point Tracking (MPPT). PWM controllers are more budget-friendly and MPPT controllers are more efficient.
The biggest difference is in how they harness solar energy — PWM controllers draw power from solar panels at a voltage slightly higher than the battery’s, resulting in some energy loss. MPPT controllers optimise energy capture by drawing power from the panels at their peak voltage, maximising power output.
Why isn’t my solar controller working?
Solar charge controllers are complex devices that connect multiple moving parts of a home solar panel and battery system. As such, there could be a number of reasons why a solar controller isn’t working, from a blackout triggering a fuse to everyday wear and tear.
Some of the most common problems that might alert you to an issue with your solar controller include:
- the solar controller no longer charging your battery properly;
- issues with the voltage control from the panels; or
- the controller not turning on.
What should I do if my solar controller isn’t working?
If you find that your solar controller is not working as it should, look into potential causes. A larger issue could be impacting your solar panels or battery.
As a starting point, ensure that all working parts of the solar controller and adjoining system are clean and clear of shading or obstructions. Once this is completed, and it is safe to do so, ensure the wiring from the solar controller is adequately connected to the rest of the system
By this stage, if you are still seeing issues, it might be time to safely perform a soft or hard reset of the controller itself.
Read More: Solar panels not working? Here are six common problems for solar systems that could be the cause.
How to reset a solar controller
There are two different ways to reset your solar controller: a soft reset or a hard reset. A soft reset will simply reboot the system, while a hard reset will bring the system back to its original factory settings. In most cases, it’s always best to try a soft reset first as a hard reset means that saved data could be lost.
Homeowners should not attempt to complete any electrical repairs without the help of a licensed professional. Any kind of reset on your solar controller should be performed under supervision when your solar panels are using the least amount of power, to avoid unintentional damage to the system, e.g. at night.
How to reset MPPT solar charge controller vs a PWM solar charge controller
Depending on what type of solar controller you have — whether it be a PWM or MPPT system — the instructions for the reset may differ greatly. As such, you should always refer to your solar controller’s user manual before attempting a system reset to ensure the correct steps are being taken.
As a general guide, a soft reset for a solar controller can be performed by doing the following:
- Press and hold all the buttons on the front of the solar controller for about 15 seconds
- Once you see the screen start to reboot, release the buttons
If you complete these steps and still see no changes to the solar controller, then it might be time to perform a hard reset. Again, it is best to refer to your user manual for instructions before attempting a hard reset of your PWM or MPPT solar controller.
For a hard reset, you could try the following:
- Remove the controller from its mount and unplug the wires, keeping note of where each wire was connected.
- Let the controller sit unplugged for about 15 minutes.
- Reconnect the disconnected wires back to their corresponding ports.
Please note, you should only attempt a hard reset if it is safe to and you feel confident in doing so. If you have any concerns or questions regarding a reset of your solar controller it is best to contact the manufacturer before attempting any resets yourself. Alternatively, it may be helpful to contact a solar electrician or your solar installer for further assistance.
Solar plans and providers
Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on the Ausgrid network in Sydney but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 3900kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.
Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on the Citipower network in Melbourne but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 4000kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.
Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on the Energex network in Brisbane but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 4600kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.
Here are some of the cheapest solar-specific deals from the retailers on our database. These costs are based on SA Power network in Adelaide but prices will vary depending on your circumstances. We show one product per retailer, listed in order of lowest price first. Annual price estimates assume general energy usage of 4000kWh/year for a residential customer on a single rate tariff. Price estimates exclude solar feed-in tariff credits. These are products from referral partners†. Our database may not cover all deals in your area, and please check retailer websites for up to date information.
My solar controller still isn’t working: What should I do?
If you’ve attempted both a soft and hard reset of your solar charge controller and find it still isn’t getting the job done, it may be time to purchase a new one. It might also pay to organise a system maintenance check for your solar panel and battery system, as there could be bigger issues at play.
Solar systems should be serviced at least once every five years to ensure everything is working as it should. If you can’t remember the last time you had your system checked then it could be time to organise a service, particularly if you are still within your warranty period.
To organise a solar system maintenance check, contact your solar installer or panel, battery or inverter manufacturer.
See the best-rated solar installers in Australia
Image Credits: Nataliia Martynets/shutterstock.com
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