Generac XG7000E and Interlock Kit

[jwelectric]

The generator neutral is bonded to the ground at the generator.

As it should be

He also said that some inspectors require that you install a ground rod in such installations, and about half the articles that he reads about generators say that the generator should be grounded at its site, and the other half say that this is second ground is unnecessary.

This alone is enough to prove that there is a lot of misunderstanding when it comes to these stand-alone generators

I haven’t installed a ground rod at the generator.

And there is no need to as long as the generator is being used as outlined in 250.34(A)
Being that it is in another building (shed) then 250.32 and 225 Part II comes into play which would require the grounding electrode system to be installed at both places. To install the rod at the shed would cause no harm to anything

I was speaking to the engineering manager at the manufacturer about another issue about the generator, and while doing so, he brought up the grounding issue He said that he disagrees with UL about requiring bonded neutrals. He told me that it is best if I have an electrician convert the generator to a floating neutral if I am going to connect it to my house wiring.

You mean the person that wants to ensure the sale of their product?

At the same time, he said that there has never been a record of a fatality caused by having a bonded neutral generator hooked up (legally) to house wiring. He also said that the GFCI’s will no longer work if I was to use the generator in some other way if I changed it to a floating neutral.

He meant to say that none that he knew of. During Katrina there were at least two documented deaths involving these generators. He also meant to say that if the receptacle that is supplying the house is GFCI protected then the device will trip if it is bonded on both ends.

What should I do?

Based on what I have read I would recommend a larger generator
If this is out of the question then I would have someone install a transfer that also switched the neutral.

My preference would be not to have the generator’s innards altered, as it may void the warranty. I can install a ground rod in half an hour, but I’ve also heard that this can do more harm than good.

OI agree with you on not altering the wiring of the generator but suggest the change of transfer switches. Installing a rod at the generator will cause no harm at all

I'm also more concerned with safety than with complying with code, if code outlines an unsafe situation. (Please don't suggest extension cords - I can't run 240 v appliances with them, and don't feel that having extension cords running throughout my house is safe).

The NEC is a minimum safety standard. To do anything less than what it requires will be an unsafe installation plain and simple. I know that there are a lot of folks that think they are wiser than a document that has been around for more than a hundred years and is constantly being revised by some of the greatest electrical minds in the world but I think you are smart enough to figure that one out yourself.

An IEEE article

This is concerning a different animal than what you have and would have no reflection at all on your installation

By the way, JW Electric, I would be interested to know more about the refueling fire. Was he refueling a hot generator that had been running and had just run out of gas (could the fire have been caused by heat?), or was it a cold generator that was hooked into his panel through a transfer switch, and the cause of the fire was unclear, but pointed to an electrical issue? Could an undischarged capacitor in the generator have caused the fire? Was he refueling a generator while it was running?

Facts that are known;
It was a stand-alone generator
Connected to the home via a cord
Panel front transfer
Neutral bonded on both ends

What is assumed:
He made the comment that he felt a shock which would lead one to think he was refueling while the unit was running
The fire started due to the generator being in use.

Summary:
A generator was connected to the premises wiring via a panel interlock. The generator had a neutral bond as well as the neutral bond in the service equipment. This caused a parallel path on the neutral and equipment grounding conductor between the generator and the service equipment.
The victim stated that he felt a shock which caused involuntary movement causing a large spill of fuel causing the fire.
Based on the statement of victim, “I felt a shock” it is understood that the generator was running while being refueled.

[DonL]

I’m a homeowner and am thoroughly confused after reading this and other articles about grounding a generator. (I'm not an electrician, but am a licensed ham radio operator, so I know a little more about electricity and electronics than most homeowners, but honestly, not that much).

If you are using any Radio Equipment or have any antennas in operation at your house then it would be a good idea to Install a ground rod next to the generator and wire it to the generator.

That would help to eliminate any RFI produced by the generator, Noise normally heard on HF Frequencies.

It would also provide better lightening protection for your house, Just in case one of your Radio Antennas get struck by lightening.

Your antennas should be grounded properly also.


That may not be in the NEC® code, But rather something that the ARRL® would recommend.

[Northerner]

If you are using any Radio Equipment or have any antennas in operation at your house then it would be a good idea to Install a ground rod next to the generator and wire it to the generator.

That would help to eliminate any RFI produced by the generator, Noise normally heard on HF Frequencies.

It would also provide better lightening protection for your house, Just in case one of your Radio Antennas get struck by lightening.

Your antennas should be grounded properly also.


That may not be in the NEC® code, But rather something that the ARRL® would recommend.

DonL: I wouldn’t operate my ham radio equipment during a power outage, unless it was for emergency communications. If so, I would use a marine battery as a power source. My antennas are not above house level, and have lightning arrestors and a ground rod.

[DonL]

DonL: I wouldn’t operate my ham radio equipment during a power outage, unless it was for emergency communications. If so, I would use a marine battery as a power source. My antennas are not above house level, and have lightning arrestors and a ground rod.

Around here we fire the Radio Equipment up to provide emergency communications for others that need it.

I hope that your Battery is grounded, lol

[Northerner]

Thanks, Drick and jwelectric. Unfortunately, I now have three different opinions, one from the manufacturer's engineering manager who has a BS in electrical engineering, 15 years' experience in the design/manufacture of portable generators and wasn't trying to sell me a generator (I called him to find out about the unit's distortion post-sale, and he brought up the floating neutral vs. bonded neutral issue without my asking) and the opinion of what I would assume are two electricians who also seem to be knowledgeable.

By the way, to clarify a couple things:

The shed is an oversized doghouse or outhouse with lots of clearance, and not a separate building that any person can fit into. I was told to run the generator with the door open if the weather was bad, and to bring it outside of the shed if the weather was good. There are two louvers inside the shed. It is essentially a three-sided, ventilated enclosure when the door is open. But this is not what my question was about – I have people locally who have seen the generator shelter feel comfortable with it.

The manufacturer’s Engineering Manager didn’t say that he doesn’t believe in bonded neutrals. He said that he believes that a generator needs a floating neutral only when connected to house wiring. He also said that this could cause problems if the generator with a floating neutral is then used if it is not connected to the house wiring, because then it would no longer have ground protection.

[Northerner]

Alas, I wouldn't ground my marine battery, which probably would put me at al kinds of risk (especially when you consider that my 100-watt transmitter has an earth ground).

My best ham radio rig for emergency communications is in my car, and yes that is well-grounded to the chassis. But if that was unnecessary during Hurricane Irene, when even our roads were gone, I doubt if it will be necessary in the future.

[jwelectric]

Thanks, Drick and jwelectric. Unfortunately, I now have three different opinions, one from the manufacturer's engineering manager who has a BS in electrical engineering, 15 years' experience in the design/manufacture of portable generators and wasn't trying to sell me a generator (I called him to find out about the unit's distortion post-sale, and he brought up the floating neutral vs. bonded neutral issue without my asking) and the opinion of what I would assume are two electricians who also seem to be knowledgeable.

By the way, to clarify a couple things:

The shed is an oversized doghouse or outhouse with lots of clearance, and not a separate building that any person can fit into. I was told to run the generator with the door open if the weather was bad, and to bring it outside of the shed if the weather was good. There are two louvers inside the shed. It is essentially a three-sided, ventilated enclosure when the door is open. But this is not what my question was about – I have people locally who have seen the generator shelter feel comfortable with it.

The manufacturer’s Engineering Manager didn’t say that he doesn’t believe in bonded neutrals. He said that he believes that a generator needs a floating neutral only when connected to house wiring. He also said that this could cause problems if the generator with a floating neutral is then used if it is not connected to the house wiring, because then it would no longer have ground protection.

What he is telling is all true but we also have the NEC and its requirements to contend with. We have the installation instructions outlined by the UL White Book which must be adhered to for the installation to be proper and correct and safe.

The one thing that I as well as others will quickly tell you is to not float the neutral at the generator as several thing could go wrong and you will be left holding the bag.

[jwelectric]

The shed is an oversized doghouse or outhouse with lots of clearance, and not a separate building that any person can fit into.

Doesn't matter the size.

250.32 Buildings or Structures Supplied by a Feeder(s) or Branch Circuit(s).

(A) Grounding Electrode. Building(s) or structure(s) supplied by feeder(s) or branch circuit(s) shall have a grounding electrode or grounding electrode system installed in accordance with Part III of Article 250

225 II. Buildings or Other Structures Supplied by a Feeder(s) or Branch Circuit(s)


The only thing that matters is that it is a Structure

I will add that I wouldn't install an electrode unless I was planning on an inspection

[Northerner]

Thanks for giving this your time.

[DonL]

The term Structures in NEC rules need to be better defined.


Nonbuilding structures, also referred to simply as structures, are those not designed for continuous human occupancy. The term is used by architects and structural engineers to distinctly identify structures that are not buildings.


Examples of nonbuilding structures:

Steam Generators
Aerial lift pylon
Boat lifts
Bridges and bridge-like structures (aqueducts, overpasses, trestles, viaducts, etc.)
Building canopies
Chimneys and smokestacks
Dams
Water towers
Electric power transmission towers
Ferris wheels and observation wheels
Furniture
Monuments
Parking structures
Offshore oil platforms (except for the production and housing facilities)
Packaging
Pallet rack
Piers
Roller coasters
Retaining walls
Sewers
Ships and boats
Sports equipment
Cranes
Automobiles
Machinery
Structures designed to support, contain or convey liquid or gaseous matter, including
Cooling towers
Pipelines
Distillation equipment and structural supports at chemical and petrochemical plants and oil refineries
Storage tanks
Television and radio masts and towers
Tunnels
Wharves


I believe that may include dog houses, Unless the Dog can talk.

[jwelectric]

Per the NEC

Structure. That which is built or constructed.

A 4x4 post in the ground to hold something electrical is a structure

[DonL]

Per the NEC

Structure. That which is built or constructed.

A 4x4 post in the ground to hold something electrical is a structure

OK then everything on earth is a built structure.

We can not connect anything electrical to anything electrical.

Makes more sense now...

[jwelectric]

It simply means that should you decide to wire something from one structure to another with anything other than a single circuit a grounding electrode system must be installed as well as a means to disconnect the structure from the source of power.