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#1
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Grounding wire from panel to gas pipe???
When we had our electric service upgraded, the electrician (as
expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks |
#2
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Grounding wire from panel to gas pipe???
Take a look at your gas pipe near the meter. I bet there is a tag or
sticker that states the following. "Under cathodic protection, do not ground" blueman wrote: When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks |
#3
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Grounding wire from panel to gas pipe???
Both pipes should be at the same electric potential (ground) since
they are both are buried. The grounding is done to help ensure the electrical panel has a true ground. In some cases the panel ground is wired to a long steel pole driven into the earth. Just different ways to do the same thing. Brad blueman wrote: When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks |
#4
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Grounding wire from panel to gas pipe???
In article . com, "Brad" wrote:
Both pipes should be at the same electric potential (ground) since they are both are buried. The grounding is done to help ensure the electrical panel has a true ground. Wrong, wrong, wrong, wrong. The water piping is bonded to the electrical ground in order to insure that the _water_piping_ has a true electrical ground -- IOW, to prevent the water piping from becoming live in the event of an electrical fault somewhere. -- Regards, Doug Miller (alphageek at milmac dot com) It's time to throw all their damned tea in the harbor again. |
#5
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Grounding wire from panel to gas pipe???
On Mon, 31 Jul 2006 19:33:04 GMT, Doug Miller wrote:
In article . com, "Brad" wrote: Both pipes should be at the same electric potential (ground) since they are both are buried. The grounding is done to help ensure the electrical panel has a true ground. Wrong, wrong, wrong, wrong. The water piping is bonded to the electrical ground in order to insure that the _water_piping_ has a true electrical ground -- IOW, to prevent the water piping from becoming live in the event of an electrical fault somewhere. The first poster had it right. The water piping is already at ground because it is in direct contact with the ground. Unless of course you have your water brought to you on pipes suspended in the air. Or perhaps you have it flown in? |
#6
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Grounding wire from panel to gas pipe???
water pipe today is frequently plastic and as such is no ground........
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#7
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Grounding wire from panel to gas pipe???
water pipe today is frequently plastic and as such is no ground........
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#8
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Grounding wire from panel to gas pipe???
Brad wrote:
Both pipes should be at the same electric potential (ground) since they are both are buried. Wrong, wrong... Someone already mentioned the words "cathodic protection" with respect to gas pipes. What that means is that the gas company has connected a low voltage source between a metal anode buried in the earth and the gas main and the pipes leading off it to each user. The purpose is to make the pipes slightly more electrically negative than ground so that they don't get eaten away by galvanic corrosion. The same sort of active protection is sometimes used at boat marinas and on buried metal structures like guy wire anchors. The systems are also known by the names "active cathodic protection" or "impressed current protection". There's a dielectric (insulated) coupling somewhere near the gas meter to insulate the gas pipe in your house from the buried main and feeder so that you don't "short out" that deliberately applied protection voltage, because the gas pipe in your home probably gets electrically grounded through some gas appliance it's connected to. The use of plastic buried gas piping has eliiminated the need for those kinds of corrosion protection systems on new work. The grounding is done to help ensure the electrical panel has a true ground. In some cases the panel ground is wired to a long steel pole driven into the earth. Just different ways to do the same thing. Brad blueman wrote: When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) "Rudeness is the weak man's imitation of strength." |
#9
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Grounding wire from panel to gas pipe???
"blueman" wrote in message ... When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks The correct term is "Bonded". The current code as written requires that all interior metal piping be bonded together. This can be accomplished by using #6 copper wire and approved clamps. It is common in New Jersey to bond the hot and cold water pipes together at the water heater location. It would be very easy to continue the bonding wire to the gas pipe at the water heater. Some jurisdictions do not require that the gas pipe also be bonded. Some gas companies do not want their pipes bonded. The electrical inspector would have noticed this and would have failed the job if it wasn't done correctly. Did the electrician also install at least one (Preferably two) ground rod? |
#10
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Grounding wire from panel to gas pipe???
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#11
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Grounding wire from panel to gas pipe???
In article , AZ Nomad wrote:
On Mon, 31 Jul 2006 19:33:04 GMT, Doug Miller wrote: In article . com, "Brad" wrote: Both pipes should be at the same electric potential (ground) since they are both are buried. The grounding is done to help ensure the electrical panel has a true ground. Wrong, wrong, wrong, wrong. The water piping is bonded to the electrical ground in order to insure that the _water_piping_ has a true electrical ground -- IOW, to prevent the water piping from becoming live in the event of an electrical fault somewhere. The first poster had it right. The water piping is already at ground because it is in direct contact with the ground. Unless of course you have your water brought to you on pipes suspended in the air. Or perhaps you have it flown in? No, he didn't. The electrical system has its own, *separate* grounding electrode. Metal water piping is bonded to the electrical system grounding electrodes to ensure that the metal water piping cannot become live, *not* to provide a ground for the electrical system. BTW... have you ever heard of plastic water piping? -- Regards, Doug Miller (alphageek at milmac dot com) It's time to throw all their damned tea in the harbor again. |
#12
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Grounding wire from panel to gas pipe???
"blueman" wrote in message ... When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks I asked that very same question to the people I shoot with at the range - all of them either are instructors for gas service or perform field repair services for the gas company. Every single one, all 3 of them, said "DON'T DO IT!!!!" shortly followed up by "Mind if we come by this week to INSPECT your service??" The gas company protects its own piping, if you must use ground wires to plumbing - use your cold water tap. Better yet save your pennies like I am and get grounded service. If I keep saving my extra money I might be able to afford it within the next 20 years - but's that's only if everything else in my life goes perfectly. |
#13
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Grounding wire from panel to gas pipe???
Click Fraud wrote:
(Doug Miller) wrote: The water piping is bonded to the electrical ground in order to insure that the _water_piping_ has a true electrical ground -- IOW, to prevent the water piping from becoming live in the event of an electrical fault somewhere. And this really is an important thing! My mother in law's dishwasher developed a short to the incoming water pipe. Most of her water piping is PVC, but some of the outside parts are metal, and NOT bonded to ground. We discovered this one day when she went to water the lawn while the dishwasher was running. She reached for the faucet, and ZAP! Fortunately, it was not lethal. Did you find out HOW the dishwasher shorted to the inlet pipe? Seems a bit hard to fathom unless whoever installed the wiring to the dishwaher didn't ground it properly. A plastic bodied water inlet solenoid valve might have insulated the inlet pipe from the rest of the dishwasher, but how did a switched hot lead contact the pipe? Maybe the solenoid valve's coil developed a short to it's case, which was electrically connected to the piping, but not to the rest of the machine. My curious mind wants to know... Jeff -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) "Rudeness is the weak man's imitation of strength." |
#14
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Grounding wire from panel to gas pipe???
On Mon, 31 Jul 2006 23:22:14 GMT, Doug Miller wrote:
In article , AZ Nomad wrote: On Mon, 31 Jul 2006 19:33:04 GMT, Doug Miller wrote: In article . com, "Brad" wrote: Both pipes should be at the same electric potential (ground) since they are both are buried. The grounding is done to help ensure the electrical panel has a true ground. Wrong, wrong, wrong, wrong. The water piping is bonded to the electrical ground in order to insure that the _water_piping_ has a true electrical ground -- IOW, to prevent the water piping from becoming live in the event of an electrical fault somewhere. The first poster had it right. The water piping is already at ground because it is in direct contact with the ground. Unless of course you have your water brought to you on pipes suspended in the air. Or perhaps you have it flown in? No, he didn't. The electrical system has its own, *separate* grounding electrode. Metal water piping is bonded to the electrical system grounding electrodes to ensure that the metal water piping cannot become live, *not* to provide a ground for the electrical system. Metal water piping burried in the ground cannot become live. It is as well grounded as possible. If you connect the house's ground to it then it is in order to keep the house's ground from being live compared to the water pipe. BTW... have you ever heard of plastic water piping? As a water source? Never. What has that to do with anything discussed? Nobody is going gto use ploastic for grounding. |
#15
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Grounding wire from panel to gas pipe???
In article , AZ Nomad wrote:
On Mon, 31 Jul 2006 23:22:14 GMT, Doug Miller wrote: In article , AZ Nomad wrote: On Mon, 31 Jul 2006 19:33:04 GMT, Doug Miller wrote: In article . com, "Brad" wrote: Both pipes should be at the same electric potential (ground) since they are both are buried. The grounding is done to help ensure the electrical panel has a true ground. Wrong, wrong, wrong, wrong. The water piping is bonded to the electrical ground in order to insure that the _water_piping_ has a true electrical ground -- IOW, to prevent the water piping from becoming live in the event of an electrical fault somewhere. The first poster had it right. The water piping is already at ground because it is in direct contact with the ground. Unless of course you have your water brought to you on pipes suspended in the air. Or perhaps you have it flown in? No, he didn't. The electrical system has its own, *separate* grounding electrode. Metal water piping is bonded to the electrical system grounding electrodes to ensure that the metal water piping cannot become live, *not* to provide a ground for the electrical system. Metal water piping burried in the ground cannot become live. It is as well grounded as possible. If you connect the house's ground to it then it is in order to keep the house's ground from being live compared to the water pipe. This is *not* correct in any respect. There is no guarantee that the electrical system's grounding electrode, and the metal water piping, are at the same potential unless they are bonded together -- despite both of them being buried in the ground. Electrical resistance in the earth is not constant, and in fact can vary widely even over short distances. I repeat: the *sole* reason for bonding metal water piping to the electrical system's grounding electrode(s) is to ensure that the water piping is at the same potential as the electrical system's ground, so that the water pipes cannot become live in the event of an electrical fault. Google is your friend, and educating yourself on this topic should be easy. -- Regards, Doug Miller (alphageek at milmac dot com) It's time to throw all their damned tea in the harbor again. |
#16
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Grounding wire from panel to gas pipe???
blueman posted for all of us...
I don't top post - see either inline or at bottom. When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks Hey Jefie is that you? Another question that been asked and answered quite a few times. Google still broke at your house aye? Take your meds... -- Tekkie |
#17
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Grounding wire from panel to gas pipe???
Eigenvector posted for all of us...
I don't top post - see either inline or at bottom. I asked that very same question to the people I shoot with at the range - all of them either are instructors for gas service or perform field repair services for the gas company. Every single one, all 3 of them, said "DON'T DO IT!!!!" shortly followed up by "Mind if we come by this week to INSPECT your service??" The gas company protects its own piping, if you must use ground wires to plumbing - use your cold water tap. Better yet save your pennies like I am and get grounded service. If I keep saving my extra money I might be able to afford it within the next 20 years - but's that's only if everything else in my life goes perfectly. Hey, good luck!!!! -- Tekkie |
#18
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Grounding wire from panel to gas pipe???
While both pipes are buried and may be made of metal, only the water line
should be used as a ground unless it is fed by a plastic pipe. The gas line should NEVER be used as a ground, although it should be grounded to the building ground, because gas supply lines can also be made of plastic, and even if it is metallic it will have an insulating fitting at the meter to prevent interference with cathodic corrosion protection of the underground lines. If you have a furnace or a powered water heater and grounded wiring, the connection through this equipment will also ground the gas lines. However, I believe NEC requires a separate cross connection to ensure proper grounding. "Brad" wrote in message ups.com... Both pipes should be at the same electric potential (ground) since they are both are buried. The grounding is done to help ensure the electrical panel has a true ground. In some cases the panel ground is wired to a long steel pole driven into the earth. Just different ways to do the same thing. Brad blueman wrote: When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks |
#19
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Grounding wire from panel to gas pipe???
I don't bottom post, at least not most of the time, and I try to be
consistent with what I say. :-) Tekkie® wrote: Eigenvector posted for all of us... I don't top post - see either inline or at bottom. ... Hey, good luck!!!! |
#20
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Grounding wire from panel to gas pipe???
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#21
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Grounding wire from panel to gas pipe???
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#22
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Grounding wire from panel to gas pipe???
Jeff Wisnia writes:
Brad wrote: Both pipes should be at the same electric potential (ground) since they are both are buried. Wrong, wrong... Someone already mentioned the words "cathodic protection" with respect to gas pipes. What that means is that the gas company has connected a low voltage source between a metal anode buried in the earth and the gas main and the pipes leading off it to each user. The purpose is to make the pipes slightly more electrically negative than ground so that they don't get eaten away by galvanic corrosion. The same sort of active protection is sometimes used at boat marinas and on buried metal structures like guy wire anchors. The systems are also known by the names "active cathodic protection" or "impressed current protection". There's a dielectric (insulated) coupling somewhere near the gas meter to insulate the gas pipe in your house from the buried main and feeder so that you don't "short out" that deliberately applied protection voltage, because the gas pipe in your home probably gets electrically grounded through some gas appliance it's connected to. The use of plastic buried gas piping has eliiminated the need for those kinds of corrosion protection systems on new work. The grounding is done to help ensure the electrical panel has a true ground. In some cases the panel ground is wired to a long steel pole driven into the earth. Just different ways to do the same thing. Brad According to your explanation, then I would think that the gas pipe SHOULD be grounded. For you say that the in-house pipe is insulated from the underground piping and hence NEITHER grounded nor "cathodic protected". Of course the pipe may end up being indirectly grounded through an appliance ground, but that seems like all the more reason for installing a solid, secure, permanent ground connection to the panel ground. After all, what if the appliance is miswired and the appliance ground is energized resulting in the pipe being energized (yet insulated from earth ground), resulting in shock just like with a water pipe... |
#23
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Grounding wire from panel to gas pipe???
"EXT" writes:
While both pipes are buried and may be made of metal, only the water line should be used as a ground unless it is fed by a plastic pipe. The gas line should NEVER be used as a ground, although it should be grounded to the building ground, because gas supply lines can also be made of plastic, and even if it is metallic it will have an insulating fitting at the meter to prevent interference with cathodic corrosion protection of the underground lines. If you have a furnace or a powered water heater and grounded wiring, the connection through this equipment will also ground the gas lines. However, I believe NEC requires a separate cross connection to ensure proper grounding. Yes, but my question remains whether to attach the gas pipe to panel ground not for the purpose of grounding the panel but for the converse purpose of ensuring that the metal pipe inside the house never gets energized. |
#24
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Grounding wire from panel to gas pipe???
"John Grabowski" writes:
"blueman" wrote in message ... When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks The correct term is "Bonded". The current code as written requires that all interior metal piping be bonded together. This can be accomplished by using #6 copper wire and approved clamps. It is common in New Jersey to bond the hot and cold water pipes together at the water heater location. It would be very easy to continue the bonding wire to the gas pipe at the water heater. Some jurisdictions do not require that the gas pipe also be bonded. Some gas companies do not want their pipes bonded. The electrical inspector would have noticed this and would have failed the job if it wasn't done correctly. Did the electrician also install at least one (Preferably two) ground rod? The electrician installed one exterior copper rod sunk in the ground and attached directly to the 200A main breaker (which is exterior to the house in a box with the meter) and then a second copper wire running from where the water source enters the house (old galvanized 1" metal pipe) to the grounding strip within the 200A Subpanel. Service Entrance 200A Main Breaker 200A Subpanel 100A Subpanel Neurtral-----[----------]----------[-----------]---------[-----------] [ | ] [ ] [ ] Earth grnd --[--------- ]----------[-----------]---------[-----------] | Water pipe -----| Note that all other subpanels feed off of the 200A Subpanel. Note I have also shown where the neutral and grounds are bonded at the main breaker. Does this make sense and is it legal? |
#25
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Grounding wire from panel to gas pipe???
"John Grabowski" writes:
The correct term is "Bonded". The current code as written requires that all interior metal piping be bonded together. This can be accomplished by using #6 copper wire and approved clamps. It is common in New Jersey to bond the hot and cold water pipes together at the water heater location. It would be very easy to continue the bonding wire to the gas pipe at the water heater. Some jurisdictions do not require that the gas pipe also be bonded. Some gas companies do not want their pipes bonded. The electrical inspector would have noticed this and would have failed the job if it wasn't done correctly. Did the electrician also install at least one (Preferably two) ground rod? Do you need to explicitly bond the hot and cold pipes together using a copper wire jumper, or is there electrical continuity through the war heater? (Note my house is all coper pipes) Also can I bond the gas pipe to the subpanel indirectly by just jumpering the gas water heater intake pipe to the cold water pipe entering the hot water heater? Or is it required to directly bond the gas intake pipe at the meter to the panel ground using a single wire? Or is all of this unnecessary since the water heater itself provides a conducting path bonding the gas pipe system to the water pipe system (and then back through the water pipe to the panel ground) |
#26
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Grounding wire from panel to gas pipe???
blueman wrote:
Jeff Wisnia writes: Brad wrote: Both pipes should be at the same electric potential (ground) since they are both are buried. Wrong, wrong... Someone already mentioned the words "cathodic protection" with respect to gas pipes. What that means is that the gas company has connected a low voltage source between a metal anode buried in the earth and the gas main and the pipes leading off it to each user. The purpose is to make the pipes slightly more electrically negative than ground so that they don't get eaten away by galvanic corrosion. The same sort of active protection is sometimes used at boat marinas and on buried metal structures like guy wire anchors. The systems are also known by the names "active cathodic protection" or "impressed current protection". There's a dielectric (insulated) coupling somewhere near the gas meter to insulate the gas pipe in your house from the buried main and feeder so that you don't "short out" that deliberately applied protection voltage, because the gas pipe in your home probably gets electrically grounded through some gas appliance it's connected to. The use of plastic buried gas piping has eliiminated the need for those kinds of corrosion protection systems on new work. The grounding is done to help ensure the electrical panel has a true ground. In some cases the panel ground is wired to a long steel pole driven into the earth. Just different ways to do the same thing. Brad According to your explanation, then I would think that the gas pipe SHOULD be grounded. For you say that the in-house pipe is insulated from the underground piping and hence NEITHER grounded nor "cathodic protected". Of course the pipe may end up being indirectly grounded through an appliance ground, but that seems like all the more reason for installing a solid, secure, permanent ground connection to the panel ground. After all, what if the appliance is miswired and the appliance ground is energized resulting in the pipe being energized (yet insulated from earth ground), resulting in shock just like with a water pipe... I agree with you on that providing as you say, the grounding is done on the house side of any insulated coupling. I was responding the the "buried thus same potential" statement, and should have made mention of the what you just did, that an "extra" ground between the panel ground and the in-house gas piping can't hurt, and may even be required by code. Jeff -- Jeffry Wisnia (W1BSV + Brass Rat '57 EE) "Rudeness is the weak man's imitation of strength." |
#27
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Grounding wire from panel to gas pipe???
There are two issues here. Providing a good ground for your electrical
service *and* grounding metal pipes in the house to prevent them from becoming energized. Grounding your electrical service... In the old days when all pipes were metal, a cold water pipe ground would do. But then there were problems with rubber grommets on water meters in basements isolating the inside water piping from the outside water piping, plastic piping run outside underground, and the ground wires becoming disconnected or damaged say by a lawnmower or whatever. So a better grounding solution was found. That is a cold water pipe ground *and* a separate ground wire run from the electrical service panel to two ground rods placed 6 ft. apart. (double back-up) Also a ground wire which electrically connects the water pipe before the water meter to the water pipe after the water meter. Grounding metal pipes/objects in the house to prevent them from becoming energized... The idea of a 3rd prong on an electrical plug (ground wire) for an electrical appliance is that the metal case of the appliance is grounded. Then should there be a loose wire which touches the metal case and a person walks up and touches the metal case, the person will not be electrocuted. Or it would trip the breaker also protecting someone from being electrocuted. Same thing with metal pipes or objects in a house. It is possible that a hot water pipe (which might be isolated because of rubber grommets) could become energized. So it is a good idea to run a ground wire from the cold water pipe to the hot water pipe (in homes with metal piping). Hot and cold water pipes are very accessible to people. Sinks, washing machine, etc. Although gas pipes are not readily accessible to people, I suppose it wouldn't hurt anything to ground this as well. If grounding the gas pipe, I think running a ground wire from the gas pipe (house side of meter) to the ground rods or to a cold water pipe ground would be best. I don't think it would be a good idea to run a separate ground wire from the electric panel to a gas pipe. Also while grounding things in the house, it is very important to ground metal objects around sinks and especially the bathroom. Like metal medicine cabinets which have a built in light fixture. The heat from light bulbs can cause insulation on wiring to melt away, then the metal cabinet can become energized. In a bathroom you are in bare feet and might be turning on the water while opening the medicine cabinet with the other hand - zap! What can go wrong... I have seen ground wires from main electrical service panels become disconnected. There could be a situation where the ground wire(s) from the main service panel become disconnected but someone ran a ground wire from there to something else like a gas pipe. Then an appliance could malfunction and this in turn could cause the gas pipe to become energized (if it was not inadvertently grounded via an appliance). So for this reason it is *not* a good idea to ground things such as this to a connection in the electrical panel, but to ground them directly to a ground such as cold water pipe and/or the ground rods. Also you can get different "ground potentials". The ground at point A may be slightly different electrically from the ground at point B. For this reason, it is a good idea to ground everything at one point. That is run all ground wires or bond various grounds to say the ground rods or a main grounding point. |
#28
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Grounding wire from panel to gas pipe???
blueman wrote:
I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? No. - Is it recommended? No, each utility does its own thing. Let the phone, and cable companies run their own grounds, to the unified ground of the electrical system. Grounding is much less a concern to the gas company with their underground architecture than it is to the electric and phone companies with their aerial ones. - Should one use the same gauge wire as for the water pipe? Yes, same gauge wire for all your grounding runs. - Any special considerations? The galvanic corrosion problem mentioned refers mixing the types of materials on the pipes and wires, don't use a copper grounding clamp on an iron pipe, and vice versa. - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? A gas appliance, such as a furnace or range, that has an electrical hookup, will ground the gas line(s) that are connected to it, so you don't need to worry about it. You need to "jump" over anything that is removable, such as the water meter, and the water heater, so that the plumbing is always grounded even if something is removed. -- Silly sig to prevent isp ad |
#29
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Grounding wire from panel to gas pipe???
"blueman" wrote in message ... "John Grabowski" writes: The correct term is "Bonded". The current code as written requires that all interior metal piping be bonded together. This can be accomplished by using #6 copper wire and approved clamps. It is common in New Jersey to bond the hot and cold water pipes together at the water heater location. It would be very easy to continue the bonding wire to the gas pipe at the water heater. Some jurisdictions do not require that the gas pipe also be bonded. Some gas companies do not want their pipes bonded. The electrical inspector would have noticed this and would have failed the job if it wasn't done correctly. Did the electrician also install at least one (Preferably two) ground rod? Do you need to explicitly bond the hot and cold pipes together using a copper wire jumper, or is there electrical continuity through the war heater? (Note my house is all copper pipes) Usually there is continuity through the water heater, however it is not an approved connection. You must use a #6 copper or #4 aluminum wire with approved water pipe ground clamps. Also can I bond the gas pipe to the subpanel indirectly by just jumpering the gas water heater intake pipe to the cold water pipe entering the hot water heater? That is how I do it. I usually run one continuous piece of bare wire through each clamp on the hot water pipe, cold water pipe, and the gas pipe on the water heater. When the inspector comes he goes straight for the water heater and sees the bonding. If you have a hot water heating system and/or a well, those pipes need to be bonded with the others as well. Try and keep the clamps back far enough so that they will not interfere and do not have to be removed to change out the water heater. Or is it required to directly bond the gas intake pipe at the meter to the panel ground using a single wire? Or is all of this unnecessary since the water heater itself provides a conducting path bonding the gas pipe system to the water pipe system (and then back through the water pipe to the panel ground) In New Jersey the above bonding is required. Check with your local electrical inspector to learn what is required in your area. There should also be a jumper wire from one side of your water meter to the other. |
#30
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Grounding wire from panel to gas pipe???
"blueman" wrote in message ... "John Grabowski" writes: "blueman" wrote in message ... When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks The correct term is "Bonded". The current code as written requires that all interior metal piping be bonded together. This can be accomplished by using #6 copper wire and approved clamps. It is common in New Jersey to bond the hot and cold water pipes together at the water heater location. It would be very easy to continue the bonding wire to the gas pipe at the water heater. Some jurisdictions do not require that the gas pipe also be bonded. Some gas companies do not want their pipes bonded. The electrical inspector would have noticed this and would have failed the job if it wasn't done correctly. Did the electrician also install at least one (Preferably two) ground rod? The electrician installed one exterior copper rod sunk in the ground and attached directly to the 200A main breaker (which is exterior to the house in a box with the meter) and then a second copper wire running from where the water source enters the house (old galvanized 1" metal pipe) to the grounding strip within the 200A Subpanel. Service Entrance 200A Main Breaker 200A Subpanel 100A Subpanel Neurtral-----[----------]----------[-----------]---------[-----------] [ | ] [ ] [ ] Earth grnd --[--------- ]----------[-----------]---------[-----------] | Water pipe -----| Note that all other subpanels feed off of the 200A Subpanel. Note I have also shown where the neutral and grounds are bonded at the main breaker. Does this make sense and is it legal? I think that the water pipe grounding conductor should have been connected at the same point as the ground rod conductor at the main breaker in order to be code compliant. Are the neutral conductor and the water pipe grounding conductor terminated separately so as to be isolated electrically from each other in the 200 amp subpanel? |
#31
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Grounding wire from panel to gas pipe???
John Grabowski wrote: In New Jersey the above bonding is required. Check with your local electrical inspector to learn what is required in your area. There should also be a jumper wire from one side of your water meter to the other. The advice to check with the local inspector (AHJ "Authority Having Jurisdiction" in electrical-speak) is proably the best advice. For those that want to read about it, EC&M (Electrical Contracting and Maintenance Magazine) has this article - http://ecmweb.com/mag/electric_code_..._20/index.html See also: http://ecmweb.com/mag/electric_code_..._17/index.html Randy |
#32
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Grounding wire from panel to gas pipe???
John Grabowski wrote: "blueman" wrote in message ... When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks The correct term is "Bonded". The current code as written requires that all interior metal piping be bonded together. This can be accomplished by using #6 copper wire and approved clamps. It is common in New Jersey to bond the hot and cold water pipes together at the water heater location. It would be very easy to continue the bonding wire to the gas pipe at the water heater. Some jurisdictions do not require that the gas pipe also be bonded. Some gas companies do not want their pipes bonded. The electrical inspector would have noticed this and would have failed the job if it wasn't done correctly. Did the electrician also install at least one (Preferably two) ground rod? ive found most inspectorsdo not enforce this code here and some are requiring only one ground rod we still use two but ground rods are nearly worthless,certain conditions dont matter how many you drive down you still dont get the 25 or less ohms to ground |
#33
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Grounding wire from panel to gas pipe???
"John Grabowski" writes:
"blueman" wrote in message The electrician installed one exterior copper rod sunk in the ground and attached directly to the 200A main breaker (which is exterior to the house in a box with the meter) and then a second copper wire running from where the water source enters the house (old galvanized 1" metal pipe) to the grounding strip within the 200A Subpanel. Service Entrance 200A Main Breaker 200A Subpanel 100A Subpanel Neurtral-----[----------]----------[-----------]---------[-----------] [ | ] [ ] [ ] Earth grnd --[--------- ]----------[-----------]---------[-----------] | Water pipe -----| Note that all other subpanels feed off of the 200A Subpanel. Note I have also shown where the neutral and grounds are bonded at the main breaker. Does this make sense and is it legal? I think that the water pipe grounding conductor should have been connected at the same point as the ground rod conductor at the main breaker in order to be code compliant. Are the neutral conductor and the water pipe grounding conductor terminated separately so as to be isolated electrically from each other in the 200 amp subpanel? Yes. That is what I was trying to show in the picture. |
#34
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Grounding wire from panel to gas pipe???
On Mon, 31 Jul 2006 16:45:10 GMT, blueman wrote:
When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks Only qualified allow qualified personnel work on electrical systems, and follow all construction codes. IMHO: 1. Required per 2005 NEC 250.104(B) 2. Required. 3. Per 250.104(b) use 250.122 as source of size. 4. Nothing special, but ensure you follow the NEC and local codes. Give your local code enforcement inspector a call. 5. 250.104(B) tells you the options you have to bonding the metal piping to. One includes bonding to the grouding electrode. If your water pipe meets the requirements of 250.52(A)(1), then it is a grounding electrode. So a water inlet piping can be used per code. Now all this is using the NEC, and guessing about your local setup. Only a qualified person working on site can help you. So this is not a how-to, but a starting point for planning your operation. Research with your local inspector, or AHJ. later, tom @ www.FreelancingProjects.com |
#35
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Grounding wire from panel to gas pipe???
In article , Bud-- wrote:
The NEC has for a very long time required that water service pipes be used as a grounding electrode. Note the word "a". Not "the". The current code REQUIRES that water service pipe with metal pipe underground length of 10 ft or more be included as a grounding electrode. And it flatly prohibits using it as the *only* grounding electrode. Because this pipe may in the future be replaced with plastic pipe, a supplemental electrode is required - usually ground rod(s). You have things backwards. The ground rod is the *primary* grounding electrode, and the water piping is the supplemental electrode. You're also wrong about the reason. "Bonding of piping systems... the basic concept is to ground any metal pipes that would present a hazard if energized by an electrical circuit." [National Electrical Code Handbook, Section 250-80] I don't know how to put it any simpler than that. -- Regards, Doug Miller (alphageek at milmac dot com) It's time to throw all their damned tea in the harbor again. |
#36
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Grounding wire from panel to gas pipe???
Doug Miller wrote:
In article , AZ Nomad wrote: On Mon, 31 Jul 2006 19:33:04 GMT, Doug Miller wrote: In article . com, "Brad" wrote: Both pipes should be at the same electric potential (ground) since they are both are buried. The grounding is done to help ensure the electrical panel has a true ground. Wrong, wrong, wrong, wrong. The water piping is bonded to the electrical ground in order to insure that the _water_piping_ has a true electrical ground -- IOW, to prevent the water piping from becoming live in the event of an electrical fault somewhere. The first poster had it right. The water piping is already at ground because it is in direct contact with the ground. Unless of course you have your water brought to you on pipes suspended in the air. Or perhaps you have it flown in? No, he didn't. The electrical system has its own, *separate* grounding electrode. Metal water piping is bonded to the electrical system grounding electrodes to ensure that the metal water piping cannot become live, *not* to provide a ground for the electrical system. BTW... have you ever heard of plastic water piping? The NEC has for a very long time required that water service pipes be used as a grounding electrode. The current code REQUIRES that water service pipe with metal pipe underground length of 10 ft or more be included as a grounding electrode. Because this pipe may in the future be replaced with plastic pipe, a supplemental electrode is required - usually ground rod(s). For new construction use a Ufer ground/concrete encased electrode. These electrodes are connected together to make a grounding electrode system. The earthing resistance of a metal municipal water system is lower than anything you can provide in a house. bud-- |
#37
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Grounding wire from panel to gas pipe???
John Grabowski wrote:
"blueman" wrote in message ... "John Grabowski" writes: "blueman" wrote in message ... When we had our electric service upgraded, the electrician (as expected) ran a ground wire from the cold water main inlet to the ground on the panel. I read somewhere that one should also run a similar grounding wire to the natural gas pipe inlet but the electrician didn't do that. - Is it required by code? - Is it recommended? - Should one use the same gauge wire as for the water pipe? - Any special considerations? - Can I daisy chain it from the water pipe or do I need to run a separate ground back to the panel? Thanks The correct term is "Bonded". The current code as written requires that all interior metal piping be bonded together. This can be accomplished by using #6 copper wire and approved clamps. It is common in New Jersey to bond the hot and cold water pipes together at the water heater location. It would be very easy to continue the bonding wire to the gas pipe at the water heater. Some jurisdictions do not require that the gas pipe also be bonded. Some gas companies do not want their pipes bonded. The electrical inspector would have noticed this and would have failed the job if it wasn't done correctly. Did the electrician also install at least one (Preferably two) ground rod? The electrician installed one exterior copper rod sunk in the ground and attached directly to the 200A main breaker (which is exterior to the house in a box with the meter) and then a second copper wire running from where the water source enters the house (old galvanized 1" metal pipe) to the grounding strip within the 200A Subpanel. Service Entrance 200A Main Breaker 200A Subpanel 100A Subpanel Neurtral-----[----------]----------[-----------]---------[-----------] [ | ] [ ] [ ] Earth grnd --[--------- ]----------[-----------]---------[-----------] | Water pipe -----| Note that all other subpanels feed off of the 200A Subpanel. Note I have also shown where the neutral and grounds are bonded at the main breaker. Does this make sense and is it legal? I think that the water pipe grounding conductor should have been connected at the same point as the ground rod conductor at the main breaker in order to be code compliant. I agree. The NEC requires the water service pipe (if 10 ft or more length underground) to be connected to the ground/neutral at the service disconnect, along with the ground rod. Also connecting it to the ground bar in the subpanel is OK. bud-- |
#38
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Grounding wire from panel to gas pipe???
Jeff Wisnia writes:
blueman wrote: Jeff Wisnia writes: Brad wrote: Both pipes should be at the same electric potential (ground) since they are both are buried. Wrong, wrong... Someone already mentioned the words "cathodic protection" with respect to gas pipes. What that means is that the gas company has connected a low voltage source between a metal anode buried in the earth and the gas main and the pipes leading off it to each user. The purpose is to make the pipes slightly more electrically negative than ground so that they don't get eaten away by galvanic corrosion. The same sort of active protection is sometimes used at boat marinas and on buried metal structures like guy wire anchors. The systems are also known by the names "active cathodic protection" or "impressed current protection". There's a dielectric (insulated) coupling somewhere near the gas meter to insulate the gas pipe in your house from the buried main and feeder so that you don't "short out" that deliberately applied protection voltage, because the gas pipe in your home probably gets electrically grounded through some gas appliance it's connected to. The use of plastic buried gas piping has eliiminated the need for those kinds of corrosion protection systems on new work. The grounding is done to help ensure the electrical panel has a true ground. In some cases the panel ground is wired to a long steel pole driven into the earth. Just different ways to do the same thing. Brad According to your explanation, then I would think that the gas pipe SHOULD be grounded. For you say that the in-house pipe is insulated from the underground piping and hence NEITHER grounded nor "cathodic protected". Of course the pipe may end up being indirectly grounded through an appliance ground, but that seems like all the more reason for installing a solid, secure, permanent ground connection to the panel ground. After all, what if the appliance is miswired and the appliance ground is energized resulting in the pipe being energized (yet insulated from earth ground), resulting in shock just like with a water pipe... I agree with you on that providing as you say, the grounding is done on the house side of any insulated coupling. I was responding the the "buried thus same potential" statement, and should have made mention of the what you just did, that an "extra" ground between the panel ground and the in-house gas piping can't hurt, and may even be required by code. Jeff Well, I called our local gas company (Keyspan) and after a few handoffs, I was told that they do NOT recommend grounding the gas pipe. In fact, they say that if they see such a bridging on a service call, they typically remove it. |
#39
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Grounding wire from panel to gas pipe???
In article , Bud-- wrote:
Doug Miller wrote: In article , Bud-- wrote: The NEC has for a very long time required that water service pipes be used as a grounding electrode. Note the word "a". Not "the". So what? Metal water service pipes (10 ft or longer) are REQUIRED by 250.50 to be a part of the grounding electrode system. This basic requirement has been in the code for a very long time. "A part", yes -- but it is not permitted to be the *only* grounding electrode. Ground rods are not required to be installed. Technically true, but misleading. You may use a ground rod, a ground plate, a buried wire ring, or the metal framing of the building, as the *only* grounding electrode. But not a water pipe. The current code REQUIRES that water service pipe with metal pipe underground length of 10 ft or more be included as a grounding electrode. And it flatly prohibits using it as the *only* grounding electrode. So what? See reason. Because this pipe may in the future be replaced with plastic pipe, a supplemental electrode is required - usually ground rod(s). You have things backwards. The ground rod is the *primary* grounding electrode, and the water piping is the supplemental electrode. You have things backwards. With a water pipe a "supplemental" electrode is required - 250.53-D-2. A "supplemental" ground rod is a strange name for the "primary" grounding electrode. The Code permits using a ground rod, alone, as the grounding electrode. It prohibits using a water pipe, alone, as the grounding electrode. Quibbling over which is "primary" and which is "supplemental" doesn't change those facts. Grounding rods are 'good' if their resistance to earth is 25 ohms or less (or use 2 rods and it doesn't matter). Municipal water pipe earth resistance is typically under 3 ohms. Irrelevant. The Code does not permit a water pipe to be the only grounding electrode. Again: "Bonding of piping systems... the basic concept is to ground any metal pipes that would present a hazard if energized by an electrical circuit." [National Electrical Code Handbook, Section 250-80] I'm not sure why you're having so much trouble grasping this. -- Regards, Doug Miller (alphageek at milmac dot com) It's time to throw all their damned tea in the harbor again. |
#40
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Grounding wire from panel to gas pipe???
Assume underground metal water service pipe (10ft...) and a ground rod.
Your original statement was: Metal water piping is bonded to the electrical system grounding electrodes to ensure that the metal water piping cannot become live, *not* to provide a ground for the electrical system The underground water service pipe is REQUIRED by the 250.50 to be included as a grounding electrode. It has been thus fire was invented. Bonding requirements under 250.104-A (not 250.80) have been already met under the more stringent 250.50. The code clearly requires the water service pipe to be a grounding electrode. The water pipe clearly provides “A GROUND FOR THE ELECTRICAL SYSTEM.” If 250.104 was removed, the connection would still have to be made. If the water service pipe was plastic 250.104 would prevail. Both Brad and AZNomad said the water pipe was a grounding electode. So far no one agrees with you. You said: The ground rod is the *primary* grounding electrode, and the water piping is the supplemental electrode. 250.53-D-2. requires a "supplemental" electrode - your ground rod. The water pipe is clearly superior based on the size of grounding electrode conductor required for each electrode and by typical earth resistances. You said: You're also wrong about the reason The NFPA Handbook said the rod was there because the water pipe might be replaced in the future with plastic with the rod as a "supplementary" fall-back. I'm not sure why you're having so much trouble grasping this. bud-- |
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