Installing home standby generator--grounding question

[geo25g]

Hello, I purchased a home standby generator from Generac (www.genarc.com) called the Guardian,in the installation instructions it states that the generator must be grounded,(they provide a ground connection on the back of the unit), because I live in NJ we are required to have two ground poles installed with at least 6 feet between them these were installed when the house was built.

The generator will be attached to the electrical panel via a automatic transfer switch so when the power fails the transfer switch will automatically turn on the generator and power the house,all of the current ground wires attach to one of the ground poles with a jumper to the 2rd one.

My question is can I connect the ground wire from the new generator to the 1st ground pole along with the ground wires from the electric panel. (I'm only a home owner) Would this be within code???

I did purchase a 5/8 copper ground pole along with the acorns,(this can be returned), should I install a 3rd ground pole and connect all three in series???

I am thinking that since the generator is being attached to the electric panel and will supply all the electric to my home in the event of a power failure, the ground should be attached to the existing grounding poles is this correct..

I'm sorry I may not have enough information about the generator thats why I listed the web site (www.genarc.com) if you need more information to answer my question.

Thank You for your help.. George

 

[Ed MacLaren]

Re: Installing home standby generator--grounding question

George, please consider hiring a qualified electrician who has experience with generator installations.

There are other important considerations, in addition to the grounding, that, if not done correctly, can result in damage or injury.

Ed

[ September 24, 2003, 10:49 PM: Message edited by: Ed MacLaren ]

 

[geo25g]

Re: Installing home standby generator--grounding question

Hi Ed thank you for the reply, I am going to hire an electrician to make the connections to the main panel, but I'm trying to get the bull work out of the way. I feel an electrician should not have to be concerned with setting the generator ect. Can I connect the generator ground to the existing ground pole (for my knowledge) Thank You George

 

[Ed MacLaren]

Re: Installing home standby generator--grounding question

You should ensure that your electrician knows what a "separately derived system" is, and how to determine if your installation is one. This depends on the type of transfer switch used.

There is a big difference between connecting a grounding electrode conductor to-

1. the generator frame, and,

2. one of the generator circuit conductors.

If the generator is configured as a separately derived system, it's neutral conductor is required to be grounded (connected to a grounding electrode).

If it is not a separately derived system, the neutral is not permitted to be grounded.

And yes, if it is required to be grounded, it should be to the existing electrode.

Ed

 

[dereckbc]

Re: Installing home standby generator--grounding question

Hi Geo, you really need to consult with your electrician. As to whether or not you need to ground the generator depends entirely on if its a separately derived systems or not. It would be inappropriate for any one to answer any of your questions without knowing all the details such as SDS. Good luck

Dereck

 

[brian john]

Re: Installing home standby generator--grounding question

And from my expierence MOST generators are installed improperly. At least in our area.

Three phase 4 wire system, three pole ATS and the generator neutral is grounded at the generator.

 

[Guest]

Re: Installing home standby generator--grounding question

Exactly what portion of the work are you planning to do yourself, and what part do you farm out to the electrician?

Does your transfer switch also switch the neutral?

Answering these basic questions will help us give you a better & safer answer.

 

[geo25g]

Re: Installing home standby generator--grounding question

Thank You all for your reply, here is what I plan do install, the generator weights 487 lbs and measures 48" X 24" I poured a concrete pad that measures 50" X 27" and is 7" thick.

I plan to unpack the generator and set it on the pad, mount the pre-wired external connection box on the house, drill a hole through the wall into the garage (under the existing electric panel) for the conduit, mount the internal automatic transfer switch on the wall inside of the garage and finally have a plumber run a natural gas line to the generator (this generator runs off of natural gas not automobile gas).

ALL ELECTRICAL connections will be done by an electrician, I am a home owner not an electrician and will NOT kid myself in thinking that I can handle the wiring. (I really do appreciate your concerns.)

I had a question about the ground because when I read the installation instructions it stated that the unit had to be grounded to an earth ground,I did not know if the unit needed its own ground or if it could be attached to the two earth grounds already servicing the house. (in NJ we are required to have two earth grounds with at least 6' mim between them).

I tried to copy and paste the installation page to this post but for some reason it did not work.

Thanks Again George

 

[geo25g]

Re: Installing home standby generator--grounding question

I forgot to mention one more thing, the generator has a grounding lug on the back of the unit and the installation instructions states that the unit must be grounded to a earth ground. Once again my confusion was concerning using the existing two earth grounds or installing a new separate one for the generator.

Ed answered my question about which ground to use.
George

PS: any Ideas on how to get this thing off my truck.....

 

[tom baker]

Re: Installing home standby generator--grounding question

I looked into generator instructions and how they are wired from the factory. The generac answer is a generic one that covers all applications.
Ground rods can be installed at the generator, but if the generator transfer switch does not transfer the neutral then they are not required at the generator.
Have you electrican review section 250.30. if he or she has any questions then have them posted for us to help with.

[ September 25, 2003, 11:01 PM: Message edited by: tom baker ]

 

[geo25g]

Re: Installing home standby generator--grounding question

Hello everyone, I have to say that I have been in a lot of forums before (mostly computer related) and have found allot of miss guided information.

This forum and its members have really been great and demonstrate a genuine concern to the people posting the questions. You are all to be commended.

Thank You for your help and concern. If in the future I or anyone I know has any questions about electricity I will tell them to post it here. George