[digitalplumber]

1960's home was rewired 16 months ago with all new panel and wiring. Ground wire is clearly visible coming out of panel to stake in ground.

While doing some work in a master bath which will include re-piping with either copper or pex, I noticed an older braided ground wire attached to the piping to the shower (cold side) in the attic.

It appears this is not loose and runs back to the new panel, same location as the old. I could open and see if it is in use, but here are my ultimate questions:



If I go to pex, can this ground be moved to the black iron gas line?

If I go to copper, can this ground be moved to the copper?

Do I even need it?


Thanks

 

[tylernt]

We just replumbed from galv to Pex and I ran into this same issue. Basically, you need two grounds rods connected to your electrical Service Entrance with 6AWG copper. You also need thicker 4AWG copper attached to any metal plumbing system in the house.

Not sure about rules bonding to gas pipe.

By the way, any splices in that 4AWG wire must be permanently crimped or welded such that it cannot be disassembled (no solder either, as it would melt during a lightning strike). Crimp/weld systems typically require an expensive tool, but DIY'ers have been known to use a common $2 UL-listed ground rod bonding clamp to make the splice, and then just cut the head off the bolt. After cutting the head off, you can't disassemble it, which satisfies the spirit if not the letter of the law.

 

[TTW]

If you run 2 ground rods, you need to clamp the end of wire to the farthest rod, then run the wire to the closer rod and feed it through the clamp. No splices as tylernt said. Then it needs to go straight to the meter box or main panel. Again, it must be one continuous length of wire, # 6 bare copper is pretty standard. Around here we use standard ground rod clamps, they are made for and listed for this use.

The ground rods are 8 feet long and you need to drive the whole darn thing into and under the ground. no cutting of the ground rod allowed!

 

[Jim Port]

If you run 2 ground rods, you need to clamp the end of wire to the farthest rod, then run the wire to the closer rod and feed it through the clamp. No splices as tylernt said. Then it needs to go straight to the meter box or main panel. Again, it must be one continuous length of wire, # 6 bare copper is pretty standard. Around here we use standard ground rod clamps, they are made for and listed for this use.

The ground rods are 8 feet long and you need to drive the whole darn thing into and under the ground. no cutting of the ground rod allowed!

The conductor only needs to be continuous to the first rod, not the second. You can jumper between the two rods.

 

[TTW]

The conductor only needs to be continuous to the first rod, not the second. You can jumper between the two rods.

That's not what my instructor (Master and Inspector) taught us.

Looks like you are correct, my textbook shows a jumper between the two rods with the 2 wires on the 2'd rod clamped on separately.

I stand corrected, Thanks! (I hate to be wrong:icon_redface

 

[Jim Port]

Check the NEC and find out for yourself.

 

[TTW]

Just edited my answer, you are correct!

 

[digitalplumber]

That's not what my instructor (Master and Inspector) taught us.

Looks like you are correct, my textbook shows a jumper between the two rods with the 2 wires on the 2'd rod clamped on separately.

I stand corrected, Thanks! (I hate to be wrong:icon_redface

Can you post a picture?

 

[Billy_Bob]

It used to be that the main ground for your electrical service was to a "cold water pipe" and that was it.

Then plastic water pipe came along...

Now the electric service ground at a house is typically to two ground rods spaced 6 ft. apart. AND there is a second "ground wire" from the electric service going to the "water pipe system" (if metal pipe) to "bond" it to ground.

And in this case, we are not using the water pipe system as a "ground", rather we are making sure it is "grounded" or electrically connected to those two ground rods (and the neutral) at the electrical service.

And this is done because an electrical malfunction* can "energize" a metal water pipe system. Then grandma goes to brush her teeth in the morning, touches a metal water faucet handle, then gets electrocuted - but NOT if the metal pipes are bonded safely to ground!

*Things like a refrigerator with ice maker, washing machine, dish washer, electric water heater, etc. can have an electrical short to a metal water pipe system. Or a bare electrical wire could be touching a metal pipe somewhere. Etc.

Anyway if ALL of your water piping is plastic, which does not conduct electricity, then of course no need to bond it to ground. However if you are replacing a section of metal pipe with plastic pipe, then the REMAINING metal pipe in the house still needs to be bonded to ground. You can install electrical jumpers from one section of metal pipe past the new plastic section to the remaining metal section.

Or if the new plastic section "dead ends", no metal pipe beyond that, then just move the bonding connection to the metal pipe prior to that.

In some cases you might have...

---metal---plastic----metal---plastic---metal

You would just need to electrically connect all 3 metal sections together and be sure one section was bonded to ground at the electric service.

And water heaters can electrically "isolate" the hot water pipes from the cold via "dielectric unions", so it is common for there to also be an electrical connection from the metal cold water pipe to the metal hot water pipe at the water heater. Like this...

On dielectric unions...
http://plumberologist.com/2012/01/water-heater-fittings-dialectric-brass/

Something else "electrical" and interesting about water heaters (just for curiosity sake) is they have an anode rod inside the tank which sort of "electroplates" the tank to prevent it from developing leaks...
http://www.waterheaterrescue.com/pages/WHRpages/English/Longevity/water-heater-anodes.html

Anyway plumbing can be quite "electrical"!

 

[digitalplumber]

I looked in the box and the braided wire is connected on the panel.

So I will do as you guys suggested, another rod 6 feet away then connected to the other rods clamp.

Thanks

 

[Billy_Bob]

Note: In rare situations there can be electricity on a water pipe or electricity on a ground wire!

So if you disconnect a ground wire - and are holding the ground wire in one hand and touching the metal pipe with the other hand, you could be shocked.

Best to "assume" the water pipe and the ground wire is "live" when disconnecting it.

So first turn off the main power to the house - If any appliance is "leaking" electricity to ground, that would remove the hazard.

And wear rubber gloves when connecting / disconnecting the ground wire. (In rare situations electricity can still enter through the city's water main or the electric company's "neutral" wire - from neighbor's malfunctioning electric/plumbing systems.)

There probably will not be any such problem, but a little safety is always a good idea!

 

[Speedy Petey]

Wow, quite a bit of misinformation here.

Basically, you need two grounds connected to your electrical Service Entrance. You can either have two ground rods spaced 6' apart and connected to the Service panel with 6AWG copper wire, OR you can have one ground rod attached with 6AWG copper and then run thicker 4AWG copper and attach it to the metal plumbing system.

It's not either/or. It has to do with what the water piping is entering the structure.
If the water entrance is plastic then the attachment is simply a water bond. If the entrance is metallic then the water pipe is also acting as an electrode.

Old plumbing installations clamped on anywhere convenient, but now you are required to attach to the plumbing within 5' of where the pipe enters the dwelling.

Again, age has NOTHING to do with it.

Not sure about rules bonding to gas pipe, but I assume that too would need to be within 5' of where it enters the building.

No, not at all. Gas piping is expressly prohibited from being used as an electrode, so bonding it within 5' is not required. In fact, a separate dedicated bond is typically not required.

If dealing with the plumbing ground is going to be a pain, it may be easier to just drive a second ground rod 6' from the existing one and attach with 6AWG.

And also bond to the water piping system if it is copper or metallic.



I would caution that you should really get your facts straight before giving electrical advice. Just because you did this once does not mean you are qualified to be giving professional advice on the subject.

 

[tylernt]

I would caution that you should really get your facts straight before giving electrical advice. Just because you did this once does not mean you are qualified to be giving professional advice on the subject.

I never claimed to be a professional. This is a DIY site for DIY'ers, there is no expectation that any user is giving professional advice unless they claim to be a professional in their profile or signature, which I don't.

 

[Speedy Petey]

I never claimed to be a professional. This is a DIY site for DIY'ers, there is no expectation that any user is giving professional advice unless they claim to be a professional in their profile or signature, which I don't.

So giving the wrong advice is OK as long as you are not a professional?? Makes sense.
Oh wait, no it doesn't. :yes:

 

[TTW]

Can you post a picture?

 

[digitalplumber]

Very good thanks, is there any benefit to making it greater than 6 foot?

 

[JuzRick]

Note: In rare situations there can be electricity on a water pipe or electricity on a ground wire!

So if you disconnect a ground wire - and are holding the ground wire in one hand and touching the metal pipe with the other hand, you could be shocked.

Best to "assume" the water pipe and the ground wire is "live" when disconnecting it.

So first turn off the main power to the house - If any appliance is "leaking" electricity to ground, that would remove the hazard.

And wear rubber gloves when connecting / disconnecting the ground wire. (In rare situations electricity can still enter through the city's water main or the electric company's "neutral" wire - from neighbor's malfunctioning electric/plumbing systems.)

There probably will not be any such problem, but a little safety is always a good idea!

Very informational!!!!:thumbsup:

 

[TTW]

Very good thanks, is there any benefit to making it greater than 6 foot?

I don't think going more than 6 feet will give you any advantage.

Also, you can drive at an angle or bury if you have tough ground to get through or a ledge.

 

[tribe_fan]

I would look closely to see if one of the outlets is somehow connected to the pipe.

 

[digitalplumber]

I would look closely to see if one of the outlets is somehow connected to the pipe.

Thanks, there is not.