How to Ground the Portable Generator

Powering equipment at job sites, backing up home power supplies are some of the duties carried out by portable generators. That said though, some tasks may require grounding your portable generator. Thus, knowing what you need and how to do this can save you from possible injuries.

This article explains in detail what grounding is, how to know whether grounding your generator is necessary, the required grounding tools, and the grounding process for your generator.

What is Grounding?

Grounding is a process that involves linking an electrical circuit to a reference ground.

For a generator, the generator’s frame functions as the electrical circuit whereas a well-fixed grounding rod as the reference ground.

For safe operation, it is advisable to connect a copper wire from the frame of the generator to the grounding rod area.

Do I need to Ground my Portable Generator?

If there is no available manual, you can conduct the following checks for purposes of proper safety.

  • You will require using a grounding rod if your generators system is separately derived.
  • Your generator won’t require any grounding if its system isn’t separately derived.

You only need to check your generators transfer switch to know a system that is separately derived. A derived system that is not separated has a transfer switch which is not transferable to the neutral ground of the conductor.  This means that there won’t be need for any link to the grounding rod.

Majority of the portable generators have their engines, fuel tanks, and housing has been connected to the frame. This places them in a point where no grounding is needed.

How to Ground Portable Generator Guide

Needed Tools

If you must ground your generator, then you need to have the right grounding tools for best results. You can opt to have the grounding tools at your house, even though they are available at the working site. This checklist helps you stay prepared any time you wish to use your moveable generator.

Solid Copper Grounding Wire: a large amount of copper wire is necessary for connecting the wire to the generator. It also connects to the copper ground rod and some remains as spare for any other use.

A Set of Wire Strippers: stripping the copper wires is necessary for their proper connection to the generator and copper rods. In addition, a nice set of wire strippers helps make the process easier, safer, and cleaner. A sharp object or a knife is ideal for stripping within a pinch.

4 Foot Copper Ground Rod: the ground copper rod is the most important tool. Having the correct copper grounding rod makes the whole difference in the grounding procedure effectively. The desired copper ground length should be at least 4 feet. You will also be required to check how far down it can get into the ground.

Hammer/Sledge Hammer/Mallet: you will definitely require a tool to drive your copper rod into the ground. A quality sledgehammer, mallet or hammer is thus required. Use it with care so that the coating of the copper rod is not damaged. Damaging it will result in a poor connection.

Pliers: a quality set of pliers is necessary for winding the copper wire tightly around the grounding rod region. The pliers also better the connection.

Wrench: this tool is important for loosening a bolt on your generator for better connection during attaching the copper wire to your generator.

Optional Supplies/Tools

Screwdriver: this tool is useful when removing grounding bolt which has no hex head or one which has been rounded off. A Phillips head screwdriver is the best to use.

Water: this is necessary when working on the hard ground. Water helps in softening the area and these results in time-saving.

Shovel: this can be helpful in burying the rod instead when driving the copper rod through rocky terrain.

The three steps below are to be followed when grounding your portable generator.

Install the Copper Ground Rod

Move the copper ground rod at least 8 feet for a nice ground into the ground using a mallet, hammer or sledgehammer. If you encounter problems due to the hard ground, you can use water to soften the area. Also, if you are installing the rod in a rocky area, you can bury the rod into the earth at an angle that doesn’t exceed 45 degrees.

Strip and Connect Copper Wire to Copper Rod

Once you have driven the grounding rod 4 feet down, the next step involves connecting the copper wire. You do this after stripping the copper wire. Properly do so by using a wire stripper. Thereafter, bind it firmly in the region of the copper ground using a pair of pliers.

Grounding the Generator

After successfully stripping and linking the copper wire to the grounding rod, you then connect it to your generator. You do so by cautiously stripping the next side of the copper wire to set it up for connecting.

Find a grounding bolt on the generator and loosen it enough to cover the stripped wire around it.

Then wrap the stripped wire firmly around the bolt and tighten it down to get a secure and tight connection.

OSHA Grounding Requirements

OSHA (29 CFR 1926.404(f)(3)(i)) directs that under the following circumstances, a portable generators frame ought not to be grounded or connected to the earth. It also states that the frame can act as the ground other than the earth.

  • The generator only supplies equipment mounted onto the generator and/or cord and plug-linked equipment via vessels which are mounted on your generator. This is as per 404(f)(3)(i)(A) of the act.
  • The noncurrent-carrying metal equipment parts (like the internal combustion engine, fuel tank, and the house of the generator) are connected to the equipment grounding terminals of the conductor (of the power holders which are a part of the generator via mounting), or the frame of the generator is or is connected to the generator’s frame. This is as per 404(f)(3)(i)(B) of the act.

As noticed, instead of connecting to a grounding electrode system like a rod driven into the ground, the frame of the generator substitutes the grounding electrode.

However, if the above conditions are non-existent, then a grounding electrode is needed. A ground rod is a perfect example.

If the moveable generator is supplying electric energy to a structure by connection through a transfer switch to the structure, it ought to be linked to a grounding electrode. This structure could be a shop, office, trailer, or a home.

Further, the transferred switch should be approved to be used and installed according to the manufacturer’s installation guidelines and by a competent electrician.

Bonding versus Grounding

The above are two separate generator requirements plus other electrical allotment systems. Grounding refers to a connection or establishing a connection, of electric equipment or circuit to reference ground that includes the frame of the generator. Bonding refers to the deliberate link between the neutral grounded circuit conductor and the grounding way for the generator, including the generator’s frame.

Therefore, the effective connection of the neutral conductor to the frame of the generator is necessary for using the equipment in a safe way. Regarding grounding terminal links, correct bonding of a power receptacle neutral terminal can be verified through testing by a certified electrician using the right equipment. The Ohmic resistance should be near the zero point and should not be intermittent as this signifies a loose connection.

Grounding Safety Generator Checklist

  • Maintain and run portable generators as per the manufacturer’s safety and use guidelines.
  • Never join a portable generator directly to a structures electrical system unless an open-transition transfer switch is well installed. A structure could be a home, trailer or office.
  • Correct bonding and grounding are a way of averting electrocutions and shocks.
  • Use (GFCIs) ground-fault circuit interrupters according to the instructions of the manufacturer.
  • Always plug electrical tools and appliances into the generator directly, using the cords supplied by the manufacturer. Preferably, use heavy-duty extension cords which have a grounding conductor (three-pronged cord connectors and three-wire flexible cords).
  • Join a structure to a generator only if the generators transfer switch is installed properly.
  • Inspect the equipment visually before use; get rid of defective equipment from service; tag or label it unfit for use.

Finally, grounding your generator is a very essential component of both setting up and utilizing your portable generator well. This is if your generator needs any grounding. Grounding maintains both you and your appliances (such as your generator) safe and also minimizes any malfunction changes.

Knowing how to ground your generator well can help maintain others protected even if you don’t need to ground it.

Having read the above, I’d love to hear from you if you have previously grounded a portable generator. If you have, I’d love to hear if you have encountered any troubles during your grounding process. Also, share with us your thoughts on whether grounding your generator can affect your future decision when buying a generator.

Alexey P. , Qualified Electrician and Website Founder
Alexey P. , Qualified Electrician and Website Founder

My name is Alexey P. I was born in Poland but later moved to the USA in 1998. As a well-qualified and fairly experienced electrician, I love working with DIY projects. As a result of my professional training in the field of electrical engineering, I am well versed with the key elements of the trade. I am generally knowledgeable with all inspecting codes and important regulations governing electrical components and repair. I presently live in Dover, Delaware, USA. Want to know a little about my life outside work? It is no wonder. If you encounter any challenges with your portable generator while on that camping expedition, you can count on me to help deal with that decisively. I love life. I love people. And yes, I love generators, of course!

  1. I like that you explain how generator systems that are separately derived need to use a grounding rod and that you mention checking to figure out which type you have. when setting up a system, I’d probably want to hire professionals that specialize in grounding portable generators. This could ensure that it’s set up by someone with experience and the right equipment so there aren’t any mistakes that could cause problems.

  2. HI, Is it required to ground a portable generator,if it is kept on the truck.

  3. I use three power sources to feed a portable stage lighting and sound system. One 400amp generator 3-phase for lighting, one 400 amp generator, 3- phase audio, and one 200 amp single phase 208/120 v, shore power power .
    The single phase shore power is used to run lift motors and video production bus.
    All connections are cam locks.

    The first 400 amp generator feeds a sub distro/dimmer rack and handles all lighting circuits. The second 400 amp generator handles audio (PA)/convenient outlets (stage gear), the 200amp single phase shore power feeds are split between the video ac distro and the production bus.

    .The stage is built of steel legs with rubber feet. The decking is steel frames. All deck sections are concerned with tight fitting metal camming lock devices .all stairs and hand rails are bolted on ,and all bracing is made wrench tight.
    I feel and have checked continuity of all deck materials , they are bonded by contact.
    Now, here are my questions:
    1. How do I bond the three power sources together?
    2. Will adding a ground Rod on the stage, lighting ground support, and production bus help?
    3. do I really have to run a large bonding conductor from each power source to exposed metal on the
    Structure that it serves? Or can I bond the ALL METAL together at stage area an run one bonding conductor back to a power source and then bond all three power sources together? They are all ext to each other and about 25 feet from stage area.
    4. What size copper conductor shouldI use to bond these systems?

  4. To make sure I understand…
    The body of my Predator generator is connected by a heavy wire to the frame. So, this means that I do not need to worry about grounding it?


  5. Good sharing. I like it

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