How to Ground a Generator


To ground your generator, you need to have some basic knowledge of electrical equipment, identify the type of grounding necessary, and follow safety guidelines.

With proper tools, the process of grounding a generator is very simple. In this article, we aim to simplify the generator grounding process and equip you with the practical knowledge you need to do so.

Let’s start by first discussing the types of generator grounding.

Types of Generator Grounding

Portable generator on ground in the woods

There are different ways to ground a generator; let us look at some of the most commonly used methods.

Solid Grounding

Solid grounding directly connects the generator’s neutral point to the earth using a grounding electrode, such as a rod or interconnected rod grid, buried in the earth.

This grounding method is common in low-voltage systems due to its effectiveness and simplicity.

Low Resistance Grounding

This involves a grounding resistor connecting the generator’s neutral point to the earth. This limits fault current to a detectable but safe level.

This method is preferred in high-voltage systems where fault currents can be high. The grounding resistor, usually between 1Ω and 10Ω, restrains the fault current.

High Resistance Grounding

High Resistance Grounding connects the neutral point to the earth through a high-resistance resistor. Unlike low resistance grounding, this method limits the fault current to a safe level, allowing the system to operate with a fault present.

This grounding type is typically used in continuous process industries such as chemical and petrochemical plants, where a ground fault could cause substantial damage.

Single Point Grounding

The single-point grounding technique involves connecting all equipment grounds to a single point in the system, generally a grounding bus or rod.

This reduces the risk of ground loops and electromagnetic interference, making it common in electrical and electronic systems like power distribution, communication, and control systems.

Multi Point Grounding

In contrast to single-point grounding, multi-point grounding connects different points in the system to the earth or a common ground bus.

This method is helpful in larger systems where single-point grounding may not be practical or effective.

Common Ground with Neutral Switching

This technique ties the ground and neutral conductors at a common point, usually the main service panel.

Providing a grounding point for the system while allowing for selective isolation of the neutral conductor helps prevent the formation of ground loops and reduces the risk of electrical shock.

A neutral switching device, such as a ground fault circuit interrupter, is typically employed in this setup.

Hybrid Grounding

Also known as Low Resistance Grounded-Neutral systems, hybrid grounding combines elements of both low-resistance and high-resistance grounding systems.

They mainly use this grounding type in facilities where some downtime is acceptable in case of a fault, but safety and equipment protection is still vital.

What Type of Grounding is Needed for a Portable Solar Generator?

Portable solar generators are often low-voltage systems in various settings. Usually, these generators employ the solid grounding method due to its effectiveness and simplicity.

This grounding type provides a safe path for fault currents to flow into the earth, reducing potential risks related to electrical shock and equipment damage.

But, while solid grounding is commonly used, it’s not the only suitable choice. If you use a portable solar generator with sensitive electronics, the Low-Resistance Grounding method could be more suitable.

It’s important to remember that the choice of grounding system should consider specific circumstances, including the environment where the generator will be used, the power capacity of the generator, and the types of devices it will power.

It’s always best to follow the manufacturer’s instructions and local regulations and codes when grounding a generator is crucial.

Grounding Requirements for Portable Generators by the Occupational Safety and Health Administration, USA

Occupational Safety and Health Administration (OSHA) of the United States Department of Labor provides a set of requirements for portable generators.

These requirements also apply to portable solar generators due to the fundamental similarities between these equipment. Let’s see the critical aspects of the OSHA requirements.

When Can a Portable Generator’s Frame Act as a Ground?

According to OSHA guidelines, the frame of a solar portable generator can serve as the grounding system for modern portable generators if it satisfies the following conditions.

  1. The generator only supplies equipment mounted on it or connected via a cord-and-plug through sockets on the generator.
  2. The noncurrent-carrying metal parts of equipment, such as the solar panel frame, inverter casing, and the generator’s housing, are attached to the generator frame.
  3. The equipment grounding conductor terminals (of the power sockets that are a part of the generator) are attached to the generator frame.

In these situations, the generator’s metal frame replaces the grounding electrode, negating the need for a grounding electrode system, such as a driven ground rod.

When Does a Solar Portable Generator Require a Grounding Rod?

Grounding rod for grounding electrode system

If the electrical circuit of the portable solar generator does not meet the above conditions, a grounding electrode, such as a ground rod, becomes necessary.

When the solar portable generator supplies electricity to a building through a transfer switch, it must be connected to a grounding electrode system, such as a driven grounding rod.

OSHA Safe Work Practices for Grounding Portable Generators

Here are some best practices for grounding portable generators outlined by OSHA.

  • OSHA mandates that portable generators must be maintained and operated by the manufacturer’s use and safety instructions.
  • Appliances and tools should be plugged directly into the generator using the appliance manufacturer’s supplied cords. Heavy-duty extension cords with grounding conductors should be used.
  • Equipment should be visually inspected before use, and any defective equipment should be removed from service, marked, or tagged as unsafe for use as per OSHA guidelines.
  • Cords should be appropriately rated, with heavier gauge wires replacing underrated cords.
  • Never use electrical tools or appliances with frayed cords, missing grounding prongs, or damaged or cracked housings as per OSHA guidelines.

Step-by-Step Guide to Ground a Solar Generator

Now that we know what type of grounding is needed for a solar generator and the grounding requirements, let’s see the steps for the actual process.

Tools and Equipment Requirement

To ground a solar generator, you’ll need the following tools and equipment:

  • Grounding rod: This metal rod gets driven into the ground. The type of rod can vary depending on your local electrical codes. It’s best to consult with a certified electrician for grounding rod requirements in your area.
  • Copper wire: You’ll need at least 4 feet of copper wire for grounding. The gauge and length requirements may vary depending on local electrical codes. You use copper because it’s an excellent conductor of electricity.
  • Wire stripper: This tool removes the insulation from the copper wire, exposing the conductive metal underneath.
  • Hammer: You’ll use this to drive the grounding rod into the ground.
  • Pliers: You use these to wind the copper grounding wire around the grounding rod.
  • Wrench: This tool adjusts the generator’s grounding bolt.
  • Protective fitting or clamps: These secure any ground rods above the ground, protecting anyone who may come into contact with the rod when the generator is still on.
  • Soldering Equipment (optional): If you prefer to solder metals together, you’ll need a soldering iron, solder, and flux.

6-Step Guide to Ground a Solar Generator

Solar generator grounding diagram

Here’s a detailed step-by-step guide on how to properly ground a generator:

Step 1. Find a Suitable Spot for the Grounding Rod

The ground should be soft but not extremely dry or sandy, as dry or sandy soil has poor conductivity. A slightly damp spot is ideal.

The location should also be close enough to the generator to allow the copper wire to reach but not so close as to pose a tripping hazard or interfere with the operation of the generator.

Step 2. Install the Grounding Rod

Use a mallet or sledgehammer to drive the grounding rod into the ground. The rod should be at least 3 feet deep into the ground, but deeper is better.

The deeper the rod, the better the grounding, as the soil tends to be moister and a better conductor of electricity the deeper you go.

Step 3. Prepare the Copper Wire

Use the wire strippers to remove about 6 to 12 inches of insulation from the copper wire. This bare wire will be used to make the electrical connections.

Step 4. Attach the Copper Wire to the Grounding Rod

Twist the stripped ends of the copper wire tightly around the grounding rod and secure it with the grounding clamp. Use the pliers to tighten the clamp.

This ensures a good electrical connection between the wire and the rod.

Step 5. Connect the Copper Wire to the Generator

Locate the grounding terminal bolt on your solar generator. Ensure the generator is off before proceeding.

Strip about 2 inches of insulation off the other end of the copper wire. Loosen the nut on the grounding terminal bolt, wrap the bare ends of the copper ground wire around the bolt, and tighten it with the pliers.

Then, tighten the nut back up. This ensures a good electrical connection between the wire and the generator.

Step 6. Check All Connections

Ensure all connections are secure and tight. Loose connections can lead to poor electrical grounding and potential electrical hazards.

If necessary, have a competent electrician verify the integrity of the connections.

Additional Tips for Grounding a Solar Generator

  • When forcing the copper rod into the ground, go straight down. If you’re dealing with rocky soil, go at a 45-degree angle. This will make it easier to drive the rod into the ground.
  • Avoid soggy soil. Lightly damp is best; you don’t want to put your grounding rod into a puddle. This could lead to poor grounding and potential electrical hazards.
  • Always read the manual for your generator before hooking anything up or making any decisions. The manual will provide specific instructions and warnings for your particular generator model.
  • Avoid using your vehicle chassis to ground a portable generator. The chassis isn’t earth-grounded and may not provide adequate grounding.
  • Always prioritize safety. Consult with an expert, ideally a licensed electrician, if you are working beyond your knowledge level.

Why Solar Generators Need to be Grounded

Lightning Protection

You need to ground solar generators because they contain metal parts that can get damaged if hit by lightning.

Grounding gives the electrical current from a lightning strike a direct path to the earth. This bypass protects your solar generator from severe damage.

Grounding channels the powerful electrical current from a lightning strike away from your solar generator.

This protection saves your solar system from potentially devastating damage.

Safety from Fire and Electrocution

Solar power systems are usually low maintenance. However, if there’s a problem and you must make some repairs, an ungrounded or poorly grounded solar generator can pose a serious risk.

A solar generator that’s not properly grounded can accumulate excess electricity on its parts.

This excess electricity can lead to electrocution or even cause a fire.

Preventing Static Electricity

Grounding your solar generator, whether a DIY or pre-built solar generator, helps manage static electricity. It sends any excess electricity into the earth instead of letting it build up around the solar panels and other parts.

Grounding ensures there’s no static electricity build-up, which can interfere with the functioning of semiconductors.

Without grounding, this static electricity can even lead to fires.

How useful was this post?

Click on a star to rate it!

Average rating 0 / 5. Vote count: 0

No votes so far! Be the first to rate this post.

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?