Complete guide to solar panel earthing

When installing a solar panel system, one of the most important aspects to consider is the earthing system. It is an essential component that guarantees the safety of the system and optimises its operation.

In this guide, we will explain how earthing works in solar panels, what type of earthing rod is used, how to install it, and the pros and cons of using a specific rod for solar panels.

How does earthing work in solar panels?

Grounding solar panels serves to divert possible fault currents that may be generated in the system, such as lightning strikes or insulation faults, to earth.

This protects both people and connected electrical equipment. In essence, the grounding acts as an escape route for any unwanted currents, ensuring that the system operates safely and efficiently.

Is a specific ground spike needed for solar panels?

One of the most common questions when installing a solar panel system is whether to use a specific grounding rod for the panels or whether the existing grounding rod in the electrical installation of the house can be used.

The answer depends on several factors, such as local regulations and the characteristics of the installation.In many installations, it is possible to connect the grounding of the solar panels to the house grounding rod. This can be convenient and economical, as it avoids the need to install an additional grounding rod.

However, in other cases, especially in larger installations or in locations with specific ground conditions, it may be advisable or even mandatory to use a separate grounding rod for the solar panels. This ensures more effective protection against faults and can improve the performance of the system.

Advantages and disadvantages of using your own solar panel spike

Advantages

• Increased safety: A separate grounding prong can provide better protection in case of electrical faults or shocks.

• Regulatory compliance: In some areas, it is mandatory to have a dedicated ground spike for solar panels.

• System optimisation: Having a dedicated ground spike avoids overloading the existing ground spike, which could improve system efficiency.

Disadvantages

• Additional cost: Installing an additional ground spike can increase the cost of the installation.

• Space: Requires additional space on the property, which can be inconvenient in small areas.

• Maintenance: An additional ground spike may require more maintenance and supervision.

Solar earthing diagram

The solar panel grounding diagram of a system can vary, but generally follows a standard pattern. These are the basic components of an installation:

1. Solar Panels: The panels are connected to an inverter that converts direct current (DC) to alternating current (AC).
2. Inverter: This equipment is also connected to earth to avoid any risk in case of electrical faults.
3. Junction box: From the junction box, the wiring to the earthing rod is carried out.
4. Earthing rod: The earthing cable is connected to the earthing system, either a separate earthing rod or the house earthing rod.

In this scheme, it is important that all connections are made to the grounding system.

How to earth solar panels safely

1. Gather Necessary Equipment

• Grounding Conductors: Copper wires are commonly used.
• Ground Rods: Usually made of copper or galvanized steel, driven into the ground.
• Grounding Lugs/Clamps: Attach wires to the frame of the solar panels or other components.
• Grounding Bus Bar: Centralizes the connection of all grounding wires.

2. Inspect the Solar System Component

• Check if the panel frames and mounting structure are conductive (metallic).
• Ensure that all equipment has proper grounding points, which are usually marked on the components.

3. Connect the Panel Frames to the Ground

• Attach grounding lugs to the frame of each panel.
• Run a continuous grounding wire connecting all the panel frames. Use grounding lugs to secure the wire to the frames.

4. Ground the Mounting Structure

• If the racking system is metallic, connect it to the same grounding wire as the panels to ensure continuity.

5. Connect to the Grounding Rod

• Drive the ground rod into the earth, ensuring it is in contact with moist soil for better conductivity.
• Connect the grounding wire from the solar panel system to the ground rod using a grounding clamp.

6. Test the Grounding System

• Use a multimeter or grounding tester to verify that the resistance is low (typically less than 5 ohms, depending on local regulations).

7. Connect to the Inverter and Main Ground

• Link the grounding system to the inverter’s ground terminal.
• Ensure the inverter’s ground is connected to the main service panel’s ground.

8. Inspect and Maintain Regularly

• Periodically check for loose connections, corrosion, or damage to the grounding wires or rods.
• Confirm compliance with updated safety standards.

Important Tips

• Follow local solar panel earthing requirements: Grounding requirements vary by country and region. Always adhere to your local electrical codes.
• Professional Assistance: If you want to install solar panels at home we highly recommend to avoid doing this personally and hire a solar expert like Sunhero to ensure the safety of the system.
• Surge Protection: Consider adding surge protection devices to safeguard your system from lightning strikes.

At Sunhero, we are aware of the importance of correct earthing in solar panel installations. For this reason, we evaluate each project individually, considering local regulations and the characteristics of the property, to determine the best solution.

Our team of experts design customised photovoltaic systems and ensure safe and efficient installations, using high quality materials and best practices. If you want to take a step towards solar energy, contact us now!