Grounding and earthing are crucial for safe and effective inverter installation. They ensure the metal components are at the same electrical potential as the Earth’s surface. In this blog, we will learn how to ground solar inverters and off-grid earthing techniques.
How to Ground Solar Inverter
Solar inverters can be grounded by using a grounding rod made of copper. That rod should be connected to a common grounding point and copper grounding wire is used for that purpose. It is better to have an electric panel connected to a single ground point.
Grounding solar inverter can be done using the following steps:
Step 1: First of all, proper safety must be ensured such as using proper gloves and eye protectors. The location should be far from sunlight.
Step 2: You must know how to read basic electrical codes.
Step 3: A grounding electrode should be inserted and then a grounding conductor (huge copper wire) must be connected to the ground from the ground terminal of the inverter.
Step 4: The whole system must be rechecked twice.
You must be aware of the correct method for grounding the inverter. To effectively disperse heat, inverters are equipped with an aluminum heatsink and secured with a grounding terminal to the enclosure. Connect a 6 AWG grounding wire to the grounding terminal on the inverter and connect it to a single-point grounding connection wire. This is how to ground solar inverter to avoid any mishappenings.
In off-grid systems, if a suitable grounding connection point is not available, the grounding wire from the inverter should be connected to the negative terminal of the battery bank. When it comes to grid-tied systems, the process of inverter grounding becomes more intricate and calls for the expertise of a skilled electrician.
Certain modern inverters come equipped with a grounding point connection within their circuitry. Disconnect the grounding point when connecting the inverter to a power distribution panel that already has grounding.
Ways to Avoid Double Grounding Problems
Avoid double grounding the inverter as it can potentially lead to issues. The grounding requirements for grid-tied systems may differ among countries and states and are determined based on local codes and regulations.
It is essential for a qualified electrician to carry out the installation and grounding of inverters in grid-tied applications according to the existing code regulations. The insulation manual will provide a range of options recommended by the inverter manufacturers. Thus, it remains the responsibility of the electrician to choose the method that aligns with the electrical code in your area.
Also See: 8 Reasons Inverter Keeps Switching On and Off
What is Negative Grounding in Solar Inverters?
When the negative terminal is connected to the Earth, it can be referred to as negative grounding. Negative grounding of the inverter has many benefits. It does connect with the electrical system of the home and it provides a separate earth ground. It helps when there is extra voltage in the circuit and it prevents the damaging of appliances. It also helps in discharging extra energy.
How to Do Off Grid Inverter Earthing
In this type of earthing, there is a common electrical ground that should connect the current-carrying conductor and equipment grounding system (which eventually connects the actual earth).
There are several ways of off grid inverter earthing in which an earth ground can be established, including the use of a ground rod, a ground ring made of copper wire buried in the ground, and other methods. If installed properly, a mounting pole can serve as a suitable ground.
To accurately measure the resistance between the system ground and the earth, it is crucial to employ an earth resistance meter. It is strongly advised that the ground system should have a resistance to ground that is below 5Ω.
Also Read: How to Check If Inverter is Charging Battery
Is Earthing Necessary For Inverter?
Yes! Earthing is necessary for the inverter. The unearthed inverter can cause severe shock and damage. It is important to know how to ground solar inverter for safety purposes. Ungrounded inverters have many live points that are unsafe for the human body. Proper earthing ensures the safety of the user in many ways and it can control the destruction of the system.
If interested, also check out the top 6 Solar Inverter failure causes.
What are the Types of Earthing for Solar Inverters?
Earthing is an effective method for safely redirecting electrical discharges to the ground using low-resistance wires or electrical cables. Lightning primarily takes the form of an immediate discharge of electricity. The main objective is to safeguard the appliances against voltage surges, and, most importantly, ensure the protection of users from the risk of electrocution.
These are a few earthing types for solar inverters:
1. Plate Earthing Systems
In this, a plate (made up of copper/galvanized iron) is placed in the ground vertically. This plate is inserted 3 meters above the ground level and it is made of galvanized copper or iron.
2. Pipe Earthing System
It is the most commonly used earthing system used in which a wet pit, a vertical pipe made of galvanized steel is installed. The size of the pipe primarily relies on the soil type and the magnitude of the current.
- Ordinary soil: A 1.5-inch diameter pipe that is 9 feet long is used.
- Rocky or dry soil: The diameter of the pipe should be more than ordinary soil pipe. Pipe length will be determined by soil moisture.
3. Rod Earthing System
This earthing system is like the pipe earthing system. Physically or with the assistance of a hammer, a galvanized steel pipe is inserted vertically into the ground, along with a copper rod.
Also See: How to Reset Inverter Overload
How to Ground an Inverter in an RV
For earthing an inverter in an RV, each and every part of the RV should be connected to the chassis of the RV. The solar panel, inverter, and battery bank must be connected to this single grounding point.
In the case of an inverter with RV, GFCI protection must be ensured for safety. The RV is equipped with three separate electrical systems that provide power to both the vehicle and the living area. A 12V system powers the motor, charges the battery, and operates other DC loads in the vehicle.
So, how to ground inverter in an RV? The steps to grounding are statedd below:
Step 1: Install the inverter near the coach battery bank and the shore power connection point.
Step 2: You must install the system in a cool and dry, ensuring ample ventilation for proper inverter cooling.
Step 3: The inverter should have an accessible monitor, display battery state, power draw, and error messages.
Step 4: To ensure the inverter remains in place during transportation, it should be securely fastened. Make sure to use redundancy in fastening, so that if one bolt fails, another one will secure it.
Step 5: Battery connection cables need a thick wire gauge to handle the current drawn to the inverter. Connect the inverter’s positive terminal to the battery bank’s positive terminal, and the inverter’s negative terminal to the battery’s negative terminal.
Step 6: Connect the grounding wire securely to the RV chassis with a bolt-on connection.
Step 7: Make sure to securely connect the grounding wire to the grounding connection point of the inverter.
Your RV power system’s components must have a single, unified grounding point on the RV’s chassis. For proper installation, it is essential to connect the solar panel, battery bank, and inverter to a single grounding point.
Also Read: Should An RV Inverter Be Left On When Plugged In?
Additionally, note that for grounding an inverter in a van, one needs to join the ground wire of the inverter to the chassis. The chassis ground must be then connected to the chassis of the vehicle. The basic principles for grounding an inverter in a van are almost similar.
While connecting the electrical system of an inverter to that of the van, the wires must be organized properly and checked twice.
Cross-Reference: Inverter Ground Fault Overvoltage Testing
What Happens If You Don’t Ground Inverter?
You are already aware of how to ground your inverter and not grounding a solar inverter can affect your system in many ways:
- Solar panels can be severely damaged due to lightning in off-grid inverters.
- Fire can be caused due to dysfunction of the inverter.
- It can also affect the other electrical appliances in the home as the whole system gets affected.
Now you know how to ground your solar inverter, and it can be beneficial in many ways. This is done by using a rod (preferably copper) that connects to the common point for grounding. Additionally, the prevention of fire and devastation in the system can be done through earthing only. To access more inverter-related topics, click here.
2 Comments
I’m from South Africa and install earth mats with all my solar systems.
I use a compound of carbon and concrete and water and make a slush and pour it down a hole that I make for a copper plated rod and then proceed to connect them with bare copper wire, 16 square mm in size.
I use an earth tester and with multiple rods down and apart, connecting them all together this way, I create a system that is 3ohm and connect it to the inverter and panels.
It took multiple attempts, along experts and fellow solar installers alike to understand the process.
I haven’t come across a suitable video instructing the technique on YouTube and think it would be beneficial to do a video on my next install.
It is quite fun and I achieve this with just myself and one other.
It would be helpful if you could create and share a video of the above process. We will include it in our article, and it will definitely help a lot of users.