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Joined: Jul 2004
Posts: 9,923
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G
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Quote
Describe a ground rod to a Norwegian, and he'll tell you that's the silliest thing he's ever heard of.


I bet they don't have an ass kicking thunderstorm every day for about 6 months of the year in Norway ... or Canada.

When they do I suspect they just say "there is nothing you can do about a lightning strike" and eat the blown up equipment.


Greg Fretwell
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Joined: Oct 2001
Posts: 172
W
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The rod was placed not at the tank but at the house where its GEC was attached to the piping. The gasman said it was to protect the flexible pipe he used from becoming perforated by lightning. He also said that if he had used only schedule 40 black pipe that he would not need the grounding electrode. Thanks for the 250.104(B) reference as I had not looked at that one. I would have told him that the NEC said all ground rods must be bonded as in 250.52. I guess it was best that I didn't offer my erronious view of the Code. Thanks for all the input.

Joined: Apr 2003
Posts: 139
B
Member
Originally Posted by renosteinke
...We are also assuming we understand the reason for the rod at the tank. We don't know that ... there might be another reason. For example, few people realize that fuel - be it oil, gasoline, propane, whatever - can generate it's own static when flowing. For all we know, that rod plays a role only when the tanker is filling the tank.


Again, GROUNDING will do little to nothing to equalize the charge separation created between two conductive bodies by the flow of liquids. BONDING of the liquid transfer equipment on the other hand, will help reduce the potential of static discharge.

The NPFA 77 establishs a value of 10 ohms for this purpose. However, it has been well established by both the NFPA and IEEE that bonding resistance in the area of 1,000,000 ohms is sufficient to reduce static charges on equipment.


On a side note, I am aware that my comments on grounding and bonding topics are sometimes radical and fly in the face of nearly 100 years of code practices. It has been sometime since I have been active on this forum, but I do visit the forum frequently and read most of the posts. While many of the members here know me from other forums and have come to know where I stand on cetain aspects of Article 250 and the NFPA 780, others may not and assume my comments are unfounded, unsupported, or uneducated. I apologize it it appears that I am being difficult rather than helpful. That is not my intent.

If this discussion was on the topic of say, communication towers, we may have some issues of grounding to cover. But, when it comes to the topic of "ground rods for gas piping", there really is no purpoe grounding can serve.


Bryan P. Holland, ECO.
Secretary - IAEI Florida Chapter
Joined: Jan 2005
Posts: 5,445
Likes: 2
Cat Servant
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Thank you, Bryan, for your gracious reply.

I spent a fair amount of time overseas, where I quickly learned that even the simplest tasks are capable of being performed in a manner that most would never even be able to recognize. With a wee bit of patience on my part, I nearly always found that there was a method to the madness - once you had the 'big picture.'

I have no idea why the rod was driven, or what purpose was served. Add that to the LONG list of things I don't understand. I've just seen enough to support the basic premise that folks are not stupid, and there is generally a good reason behind every practice. My ignorance of that reason does not translate into the practice being silly laugh

Joined: Nov 2005
Posts: 141
C
Member
Hi Bryan,

Sorry I haven't been able to respond until now regarding your comments.

It may seem like what we are doing is unnecessary. The reason for grounding the tanks however, is that there is usually no other way of dissipating any sudden discharge from whatever the source might be such as a really high powered FM or TV transmitter in the neighbourhood or a nearby or direct lightning strike.

We've had both the RF stuff and lightning around the tanks we've worked with and so far there has not been any issues.

The key to most of this is the codes for connections on the tanks here in Alberta. It is not allowable, to my knowledge, (unless I need some further education) in most circumstances to use any kind of metal piping and therefore, any electrical connection, from the tank and the entry point of a building for use with anything but natural gas supplied by a pipelined energy supplier. (Read the "gas company). Essentially the tank is sitting out there "on it's own" with zero protection from either RF or lightning so there is no common bonding point available.

As I said previously, we do not have a really clear rule that I can find on bonding these tanks to much of anything. I thought it would be basic to do it, and hopefully someone will be able to point me in the right direction if I'm misguided about it all here. I the meantime I think it's best to continue to try and get as tight a bond to earth as we can.

Joined: Mar 2005
Posts: 399
A
Member
The original message claimed that the ground rod was being installed because of the use of flexible gas piping. if it is coated stainless steel tubing (CSST) it is being done not to comply with 250.104 but as a manufacturers requirement to BOND the piping system to the building grounding syatem.
A seperate ground rod does not comply with the manufacturers requirements.
Different manufacturers have different requirements. Get the brand name and Google them and check their eng. spec. page.


Alan--
If it was easy, anyone could do it.
Joined: Jan 2004
Posts: 1,507
G
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Alan- My friend, while I agree with your statement regarding the bonding, the proper description of CSST is "Corrugated Stainless Steel Tubing" albeit coated the letters do not stand for coated. I should also say that the non corrugated connecting "whips" that are used for gas stove and dryer hook-ups are not what are the issue, it is the coated stuff we are talking about. There is a wealth of information on the Michigan Chapter IAEI web site at http://www.iaei-michigan.org and when there, go to products and see what each manufacturer ask for bonding.

Last edited by George Little; 03/18/08 03:50 PM.

George Little
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