fuse to breaker box

I recently began to upgrade the electrical systems in my home from mutiple fuse boxes to one main breaker box. What is the code for bonding a box and why would you do this or not do this. Also, what is the code for grounding? Ground rod, cold water pipe or both. I live in Western New York.

 

grounding and bonding have many considerations. If this is the main disconnect then you should
Connect to the water pipe within 5 feet of where it enters the house if it is metal. If not metal then you need 2 - 8 foot grounds rods 10 feet(I think, might be 6 feet) apart.
Bond the ground bus to the neutral buss.
If the main disconnect is separate. then you should
NOT bond the neutral to ground.
Run a separate ground and neutral to the disconnect.

 

Article 250 covers grounding and it is 25 pages long. It's kind of hard to summarize and get all the details and exceptions too.

But basically you need to connect to the metallic water pipe within 5 feet of there it enters your home, and you need two grounding rods 8 feet deep and at least six feet apart. You also need to connect to any other conductive materials likely to become energized.

I encourage you to go the the library and read article 250, even though it's not a particularly easy read. Don't forget to make liberal referal to the definitions in article 100 so you're sure you know what each term means. You're mainly interested in discussion of the electrical system grounding, rather than equipment grounding. Both are covered by this article.

There are also a number of books written specifically on grounding.

P.S. to Joe: you need the rods even if you have a metal water pipe.

 

Thanks for the info guys. I thought I needed both the ground to cold water and the grounding rod, but I was unaware of having two rods. I can't imagine how many homes don't comply with this. As for the bonding question, let me clarify. I have both a Main breaker panel and a sub panel in the garage. If I understand correctly the main should be bonded, but the sub panel should not be bonded. Thanks

 

Well, in certain cases, you don't need the second rod. But it's usually easier to just put it in than to do the test to see whether or not you need it. If you'd really like to see if one would be enough, call your inspector and ask what he requires. Depending on local soil conditions, he may allow you to skip the second one without a test.

In your subpanel, the neutral wires should have no connection with the grounding wires, nor with the earth if and only if you have an equipment grounding wire between panels.

 

I think you might only need one if you have metalic water pipe at least 10 feet long under ground although 2 is better. I will wait to be corrected.