Well guys lucky for me and probable unlucky for you all I found my copy of the 1996 National Eclectric Code. It had went missing since I had moved. The box was marked science and math books. Stranger yet it also contained my books on upholstery and furniture repair. Well anyway here is some info on the grounding of generators.
Article 250-83, c discusses rod and pipe electrodes. Yes galvanized pipe of three quarters of an inch or larger may be used as well as five eights inch diameter copper clad steel rod. Both are required to be a minimun of eight feet in length. They are to be driven to a depth of eight feet.. Flush or preferable below the finished grade. If rocks prevent this it may be driven at an angle between 90 and 45 degrees. If this is not possible it maybe buried in a trench no less than 30 inches in depth. Note plate electrodes may also be used, but most choose the rods. Article 250-94 table shows the smallest copper conductor to ground a service with current carrying conductors of number 1 or smaller to be number 8 if copper. Article 250-92 a speaks to protecting equipment grounding conductors. If they are exposed to physical harm all need to be in conduit. If not exposed to physical harm then number 6 and larger may be run along the structure and secured to it. Number 8 or smaller must be en conduit regardless. I found nothing in the Code that would permit using two four foot rods and tieing them together. The angle driving or trench permits the full eight foot lenth to be used. Best to use one of those methods. Now for installing the rod. Don't grab a hammer and try to pound it all the way. Dig a hole out away from any building footings. Usually two feet. Make the hole about a least a foot deep and big enough you can fasten the clamp and wire on the rod. Shove the rod down by hand as far as you can, by pumping up and down. Pull the rod out of that hole, pour the hole full of wwater. Reinsert the rod after a little time of waiting or maybe refilling the hole if the water goes down quickly. Repeat the pumping up and down with the rod by hand until it stops going easy. Pull the rod out refill with water and keep repeating this process until re moval is too difficult then resort to the sledge hammer. Usually you can get the rod down at least four to six foot before you need the hammer. This technique is called watter jetting and is also used with other equipment for horizontal boring under highways and streets for utility lines and pipes. Another note if this generator is located close to the main service point on the house there may all ready be a rod buired under the meter. It might be easier to dig it up until the wire to it is found and you could split bolt to it. Luck to you, Ron ----- Original Message ----- From: Edward Przybylek To: BlindHandyMan Sent: Sunday, December 16, 2007 9:13 PM Subject: [BlindHandyMan] Generator Grounding Follow-UP Hi all, After all your replies, I decided to ground my new generator. Better safe then sorry. When the manual said that not grounding the generator could pose the threat of electricution, it made me decide it was the best course of action. I went to Home Depot to purchase the necessary supplies. I picked up a lenght of 10 gauge stranded copper wire and then went to search for the copper grounding rod. The thing you guys forgot to mention is that the freaking rod is 8 feet long. I asked the associate how much of the rod I should cut off the 8 foot length to pound into the ground. That's when he said "All 8 feet." My first response was "Are you for real!" My soil is 5% dirt and 95% rock. Getting 8 feet of anything that deep in my yard is going to be a task meant for the Gods and not a mere mortal like myself. The last time I pounded any kind of rod into my yard was a galvanized pipe to support a newly planted evergreen to help it make it through the winter. It went down approximately 3 feet and stopped dead. I mushroomed the top of the pipe with a four pound mallet but the pipe went no further. Now you expect me to pound an 8 foot copper rod into the ground! Yeah, right. What I'm anticipating is a very bent rod and a flurry of filthy words that till make the ladies in the neighbor hood blush wildly and hurry their children indoors. From now on, gentlemen, make sure you mention the finer points of a task before making recommendations. <big smile> Let you know how it goes. Take care, Ed [Non-text portions of this message have been removed] [Non-text portions of this message have been removed]
