# Can't get ground rod driven flush.



## MDShunk (Jan 7, 2007)

It is generally recognized that a ground rod should be driven so that the full 8' length is in contact with the earth (flush or below). I was interested to know what others have done (or know to do) in situations where the only place to drive ground rods is in blacktop or concrete. I have normally drilled these surfaces to the diameter of the rod and driven the ground rod in as far as possible, while still being able to get the acorn clamp on. My inspector okay's this, even though the rod is up a few inches, since it falls into the "best efforts" category. The thought occured to me that some jurisdictions may require one to core drill out a larger hole first so that the ground rod may be driven totally flush or below and possibly chip out a groove to get the ground wire protected below the surface. How you some of you other folk feel on this matter?


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## itsunclebill (Jan 16, 2007)

I always figured the hole in concrete would fill up with dirt anyway. And since a concrete encased electrode is the prefered thing now I don't worry about the inch or 4 that's in concrete. I'm not sure lightning has an issue with the length in concrete

I always dig out asphalt to ground level with a roto hammer. After the inspectors done put it back using a torch and engineers hammer or see if I can bum a coffee can full of hot mix and a bit of tack oil from a crew in the neighborhood.

Given the variable conditions you can encounter I've often wondered if the 8' length was arrived at because the most often cut off amount was about 2' :whistling2: (no, I don't - most rods around here go in with about 20 wacks with a t-post driver, and easy enough I haven't ever used the roto hammer to drive one)


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## Speedy Petey (Jan 10, 2007)

itsunclebill said:


> ........., and easy enough I haven't ever used the roto hammer to drive one)


I hate you! 


:laughing:


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## itsunclebill (Jan 16, 2007)

:laughing: Well, it's not like that EVERYWHERE I work. I work around Cripple Creek, which is up around 9500 ft on the west side of Pike's Peak, once in a while. There's a bit more rock up there. Still, it's decomposed granite and you can drive a ground rod most places around. I try to avoid the area though 'cause I can't get any work done. There's cheap, good food at the casinos and I've been known to spend 5 or 6 dollars on the dollar breakfasts and lunches. Hard to do much after that. (well, I'm trying to make it sound like it's tough):innocent:


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## Speedy Petey (Jan 10, 2007)

I have to admit. There are two neighborhoods in my town that are all sand. You can push a rod in about 7'!


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## MDShunk (Jan 7, 2007)

I like that tip about reconstituting chipped up asphalt with a torch and hammering it back in. I'll have to try that one.


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## Magnettica (Jan 23, 2007)

MDShunk said:


> It is generally recognized that a ground rod should be driven so that the full 8' length is in contact with the earth (flush or below). I was interested to know what others have done (or know to do) in situations where the only place to drive ground rods is in blacktop or concrete. I have normally drilled these surfaces to the diameter of the rod and driven the ground rod in as far as possible, while still being able to get the acorn clamp on. My inspector okay's this, even though the rod is up a few inches, since it falls into the "best efforts" category. The thought occured to me that some jurisdictions may require one to core drill out a larger hole first so that the ground rod may be driven totally flush or below and possibly chip out a groove to get the ground wire protected below the surface. How you some of you other folk feel on this matter?



I haven't done too many new or upgraded commercial services, but what I do when this happens on a residential job is try to either fish or run the GEC to a remote area of the yard where I can drive the rods into the ground without disrupting concrete, gravel, or rock. I prefer to use a hammer drill to drive the rods and have been known to cut the ground rod it doesn't go all the way into the ground then beat the rod with a hammer to make it look like it was driven all the way in. 

C'mon... who hasn't done that?


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## MDShunk (Jan 7, 2007)

Magnettica said:


> ... and have been known to cut the ground rod it doesn't go all the way into the ground then beat the rod with a hammer to make it look like it was driven all the way in.
> 
> C'mon... who hasn't done that?


Who, me? :001_huh: 

One associate of mine used to call that "Putting it in the rest of the way with a Sawzall".

I don't exactly promote that method, but I am famaliar with the temptation. I try to drive an extra one if I have one that won't go in any more and it's too stuck to get back out.


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## Magnettica (Jan 23, 2007)

I have to drive (2) around here anyway, so...


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## macmikeman (Jan 23, 2007)

Most supply houses sell 10 foot long rods also. Now using one of those you can drive it to anyplace past 8 foot and stop. However, leaving a tripping hazard is leaving yourself open to future litigation, so a careful placement is also important.


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## sundogusa (Jan 22, 2007)

Magnettica said:


> I have to drive (2) around here anyway, so...


Same here. 2 is State rule.



MDShunk said:


> Who, me? :001_huh:
> 
> One associate of mine used to call that "Putting it in the rest of the way with a Sawzall".
> 
> I don't exactly promote that method, but I am famaliar with the temptation. I try to drive an extra one if I have one that won't go in any more and it's too stuck to get back out.


That is technically know as a #7.5 ground rod. There are others, some of the lesser knowns are #2 (which when measured surprizingly doesnot exceed 24").:laughing:


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## TheElectricalGuru (Jan 16, 2007)

Marc,

When we run into this we simply hammer drill with a chisel bit the area to break up the asphault and explain to the builder it will need to be patched. We have found that 2-3 holes tend to crumble away and allow for getting the acorn connector below the asphault.

However, if you are in the situation where the AHJ want's (2) rods regardless of the 25 or less, you then have a augmented rod to add and a bonding jumper between them and THIS would get tricky as the # 6 AWG more than likely would be subject to damage and chipping out the minimum 6' length of asphault between the rods could make someone GASP !

BUT if this is the option I would clearly make the person who OWNS the property aware of what needs to be done. AS we did this one time and what we did was use a CHOP SAW for cutting masonary , snapped a caulk line between the holes we chipped out...a wide one if I remember right and well we simply CUT a groove between the two rods and then sealed the goove with asphault compound in a DAP tube BUT the AHJ wanted to witness the connections to the acorn connectors before sealing everything up.

Anyway in most our case we have a UFER ground designed into the system and so the ground rods are not as much of a issue.


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## acrwc10 (Jan 28, 2007)

macmikeman said:


> Most supply houses sell 10 foot long rods also.quote]
> 
> 
> I don't even buy 8' rods anymore, 10' is the way to go. I know most of you are going to hate to hear this but I have a 35lb electric jack hammer with a cup head attachment, It is harder to get the hammer out of the truck then drive the rod. Once its on the rod you can hold it with one hand and in less then a minute your at grade level:thumbup: the best part I got it because a guy owed me money and gave it to me as collateral till he could get the money to pay me. When he came up with the money I bought the hammer off him with it.:laughing: also a porta-band saw.


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## sundogusa (Jan 22, 2007)

TheElectricalGuru said:


> ...BUT the AHJ wanted to *witness* the connections to the acorn connectors before sealing everything up.


What a waste of time on your part, the AHJ, and the customer...


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## MDShunk (Jan 7, 2007)

sundogusa said:


> What a waste of time on your part, the AHJ, and the customer...


I agree, but I've had the same request from a couple of inspectors. In dirt, all it takes is a few kicks with the toe of your boot to expose the connection. Sometimes, I'll drive them along a foundation of a new house, then the grade is brought up; sometimes considerably. The connection in those cases is essentially not available for inspection. That's where having a decent relationship with the inspectors pays dividends. After all, who's going to do a nice job on the whole service, and forget to tighten an acorn clamp?


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## TheElectricalGuru (Jan 16, 2007)

sundogusa said:


> What a waste of time on your part, the AHJ, and the customer...


Not a waste of time when the local AHJ requested it. He demanded it in this case on a large commercial job and if he wanted it...he go it.

Not sure how it was a waste of MY time, you can't get around the issues of compliance that easy and in his opinion I guess he wanted to see it.


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## sundogusa (Jan 22, 2007)

If you had to have a sparky standing by *waiting* on the inspector, he had to be on somebody's clock. Did the inspector make an appointment? Was he on time?
I've had the misfortune of being stood up by an inspector. He wasted my time and the customer's, since the customer was also there. I let the customer call the inspetor's boss. Seems an owner has a lot more clout than an EC. Course we only push when absolutely necessary and then gently. WE work with the AHJ more than once or twice, like an owner does.


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## TheElectricalGuru (Jan 16, 2007)

Actually like most commericial jobs, we were still on the job doing other things so it was ok for the AHJ to come anytime. The job was in an area we usually do not do work so he did not know us. In our area the AHJ's have said nothing and been fine with it.

Did not cost anyone anything...we again were still on the job.


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## Joe Momma (Jan 23, 2007)

is the 'guru' who I think it is?


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## MDShunk (Jan 7, 2007)

Joe Momma said:


> is the 'guru' who I think it is?


Not sure who you think it is, but I'm famaliar with Paul. He's okay. Don't jump on him. He knows his stuff, in general. He focuses his efforts toward educating home inspectors, to keep them from red flagging things for electricians to correct that aren't real issues, and educating them on the real issues that they should red flag. I understand that he does a little electrical contracting on the side, too. He just brings a slightly different viewpoint to this site, which is totally okay. I'm very glad to have his participation. :thumbsup:


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## TheElectricalGuru (Jan 16, 2007)

lol...he can jump on me...I dont care and I do a little more than a little electrical on the side..lol

I also educate electricians around the State of VA.....feel FREE to jump on me and get into a debate with me...I dont mind.

RadioPet on Mike Holts site......rarly post...


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## Joe Momma (Jan 23, 2007)

MDShunk said:


> Not sure who you think it is, but I'm famaliar with Paul. He's okay. Don't jump on him. He knows his stuff, in general.


Right on :thumbsup: 

It seems I've become the pit bull just dying to get out of the cage.
I'll have to work on that, thanks everyone for the proverbial 'smack upside the head' from time to time.


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## Pierre Belarge (Feb 3, 2007)

*Are Ground Rods really Effective???*

Like others here, I have issues with inspectors who demand certain items without really understanding the topic at hand.
I am an inspector, so I think I can speak about this, remember it is just my opinion  

Ground rods are usually SUPPLEMENTAL. They are also in a lot of cases when used as supplemental pretty much useless. The NEC spends a ton of ink and paper on this part of the code (Part III of Art 250). I work with the code and I am a believer in the code and processes, sometimes I just wonder how the process evolved.

When I inspect a service, the first thing I look for in the grounding process is the water, steel or concrete encasement. If there are groundrods, then I look for them. My pet peeve with ground rods is the burial of them. I do not want to see them exposed at all. I mostly look for the conductor as it leave the building and hope to see the rods completely buried. If they are 8 feet long and exposed, there are 2 violations there.


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## MDShunk (Jan 7, 2007)

Pierre Belarge said:


> If they are 8 feet long and exposed, there are 2 violations there.


Is there a good way for an inspector to know, visually, that the tip of a rod he's looking at is an 8 or 10 footer? I've always wondered. I know that one author wrote to look for the "UL" stamped into the end of a rod to know whether it was cut off or not. I buy UL marked rods, but the UL mark is on the wrapper for the bundle of rods, and is not on each rod, so that method is out the window. 

Glad to have your participation, Pierre :thumbsup:


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## Joe Momma (Jan 23, 2007)

What gives around here, it seems my post was deleted.

Is this not called "Electrician Talk"? meaning one part electrical content and the other part talk.

Didn't even get to see a reason.........

Perhaps there's just not enough posts yet to keep the moderators too busy?

(oh and I'm copying this one, just so I can read back when I can't find it, at least then I'll have some clue of what the 'higher-ups' don't like)

It seems Guru was also offended by strict policies here, funny that my delted post was to him and we're very much alike.


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## TheElectricalGuru (Jan 16, 2007)

Seems that joking is not allowed or something......anyway no worries I have nothing I need to post here but that probably will be deleted also.


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## Pierre Belarge (Feb 3, 2007)

Hello Marc, and thanks.

I am not really too interested if the rod is really 8 ft long. I just do not want it protruding above grade. There was a young child who fell on one years ago and is now living on life support and will till she passes away.
Remember the rods perform mostly no real purpose. How many houses/buildings are in service now that do not have rods? More than we can count. Lets not forget that the Utility company also has their ground as well.


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## MDShunk (Jan 7, 2007)

Pierre Belarge said:


> I am not really too interested if the rod is really 8 ft long. I just do not want it protruding above grade. .


That's my goal, as well. Even in locations where the grade is being brought up later, and I could let my rod stick up a bit, I try not to. It's just a trip hazard for the bricklayers or the sidewallers and such. 



Pierre Belarge said:


> There was a young child who fell on one years ago and is now living on life support and will till she passes away.


Wow.  What were the circumstances of that accident? Tripped over the rod, and clobbered her head? 

It's accidents that involve kids that hit home the most for me.


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## Joe Momma (Jan 23, 2007)

I can't wait to see groundrods disappear.
It seems they're also a problem for the guys pounding them too. Having to stand up high on ladder that's set on uneven soil then having to throw their weight around so much to drive the rod. It seems guys have been falling down and getting hurt.
For that reason a company came to our shop recently, telling us to cut the rods and use one of their made couplings to join the two halves just so we don't have to climb the wobbly ladder anymore.


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## JohnJ0906 (Jan 22, 2007)

Joe Momma said:


> For that reason a company came to our shop recently, telling us to cut the rods and use one of their made couplings to join the two halves just so we don't have to climb the wobbly ladder anymore.


Say what? Is this a listed product?


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## TheElectricalGuru (Jan 16, 2007)

Joe Momma said:


> I can't wait to see groundrods disappear.
> It seems they're also a problem for the guys pounding them too. Having to stand up high on ladder that's set on uneven soil then having to throw their weight around so much to drive the rod. It seems guys have been falling down and getting hurt.
> For that reason a company came to our shop recently, telling us to cut the rods and use one of their made couplings to join the two halves just so we don't have to climb the wobbly ladder anymore.


Thank GOD for large BOSCH hammer drills...lol..., We have not had to use a sledge hammer in quite a while thanks to them, but I can see my helper now missing his chance to GET EVEN.... 

I agree Joe, as the NEC starts to mandate all GE available be done and more UFERS take over the less the GR will be needed, but it is always nice to have that solution sitting their available.


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## frank (Feb 6, 2007)

*grounding rods*

Interesting topic. Here on the other side of the pond in England we use 4' grounding rods. A single rod is acceptable under any conditions providing that the Earth (ground) path Impedance is low enough to opperate a GFI within 30 milli seconds at max 30 milli amps. Electrode resistance must not be more than 200 ohms also. Otherwise use multiple series rods.

How does this compare to the USA. A couple of years ago I watched an electrician working on the downstream switchgear on a MA beach property. Activation of current devices in such sandy conditions crossed my mind.

mmmmmmmmmm! Would be nice to know

Frank England UK


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## MDShunk (Jan 7, 2007)

Frank, here in the US, the rule is 25 ohms or less. Most inspectors will permit you to just drive two 8 foot ground rods, at least 6 feet apart, without having to prove your 25 ohms. If you only want to drive one rod, many inspectors want you to prove 25 ohms. For that reason, we just drive two and call it done.


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## JohnJ0906 (Jan 22, 2007)

Frank, welcome to the forum!
I don't know how the UK is , but the NEC (National Electric Code) does not allow earth as the ground-fault current path, therefor the ground rod has nothing to do with the opperation of a GFCI, circuit breaker, fuse, etc
I have to admit, 4' ground rods sound a LOT easier to drive than a 8 footer!:laughing:


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## Joe Momma (Jan 23, 2007)

Over there, they probably only have 4 feet before running into the next ancient buried city. :laughing:


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## frank (Feb 6, 2007)

*ground rods*

Hi John

Interesting! If I understand you correctly, your ground return path is not relied upon by an electrode alone. Seems to be the same here except with the exception I mentioned.

Usually the earth path is bonded to the neutral at the consumers input. Under these conditions though special bonding arrangements are undertaken to protect aginst problems should the neutral become open circuit. We have a further system also whereby the Supply Company provide a ground via the incoming armoured cable. This is then taken back to the main Star point of the supply distribution and grounded to 'earth' and also bonded to neutral. The use of the Rod system I mentioned is allowed where the GFIC device is common to all circuits and mounted on the bus bar rail as a Mains Disconnector. Usefull if you live by the sea or as your pal says, you happen to have your house built upon some ancient architecture,


Frank. Doncaster England UK.


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## Joe Momma (Jan 23, 2007)

Say Frank, do you have any pictures of how things are done in the UK that you could post?


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## frank (Feb 6, 2007)

*Main input supplies and electrodes*



Joe Momma said:


> Say Frank, do you have any pictures of how things are done in the UK that you could post?




Of course. Give me until Thursday-ish. I should get some good photographs of the different input types for you.


Frank.


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## Joe Momma (Jan 23, 2007)

frank said:


> Of course. Give me until Thursday-ish. I should get some good photographs of the different input types for you.
> 
> 
> Frank.


Thanks a lot buddy:thumbsup: 

That would be awesome


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## frank (Feb 6, 2007)

*supply system photo's*

OK Joe.

Got the pictures. Now I have to figure out how to download them from my photobucket file.

Working on it.

Frank England UK


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## MDShunk (Jan 7, 2007)

frank said:


> OK Joe.
> 
> Got the pictures. Now I have to figure out how to download them from my photobucket file.
> 
> ...


Under each picture in your photobucket file, there is a line of code that starts with


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## Joe Momma (Jan 23, 2007)

frank said:


> OK Joe.
> 
> Got the pictures. Now I have to figure out how to download them from my photobucket file.
> 
> ...


Can't wait to see 'em

And since I fixed my phone last weekend I'll try to snap some shots of job sites from now on too. Although they would only be cell phone pictures  

But that reminds me; I think we need a specific place here for posting non-specific pictures. I know everyone likes seeing pictures, but there's not an area named "just wanted to share".


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## MDShunk (Jan 7, 2007)

Joe Momma said:


> But that reminds me; I think we need a specific place here for posting non-specific pictures. I know everyone likes seeing pictures, but there's not an area named "just wanted to share".


Just put them in the category where it seems like they make the most sense. Each picture demonstrates something.


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## frank (Feb 6, 2007)

As promised. Picture No1. Meter Cabinet. Domestic Installation.


Frank England UK


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## frank (Feb 6, 2007)

Picure No 2. Cabinet with Supply Company metering and Fuse.


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## frank (Feb 6, 2007)

Picture 3. Distribution Unit open.


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## frank (Feb 6, 2007)

Picture No 4. Distribution Unit with Lid On. Different I think from USA types.


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## frank (Feb 6, 2007)

Picture 5. Final Picture. Complete Job Ready for Customer Handover.


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## frank (Feb 6, 2007)

Small Semi Commercial 3 Phase supply system.


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## frank (Feb 6, 2007)

Small Construction Site Temporary Supply. No Ground supplied by Electricity Co. GFIC only protected. Must be tested daily. Weekly and 12 weekly. Different tests for each period.

So there we are. Some differences I think betwen USA and UK. Guess you may scratch your heads and say.why allow that???. But thats just the way it is.

By the way. Have you ever been to Mexico and seen the system there. Crocodile clips attached to any passing Pylon seems to do.

Frank Doncaster England UK.


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## frank (Feb 6, 2007)

Final Notes 


The supply system for private dwellings is usually 230 Volts. 100amps. at 50Hz. The Electricity Co will provide a armoured cable comprising 1 inner core and one oputer core wound around it, This provides Neutral and armoured protection. The system wiring is called 'concentric cableing.. The Earth (ground0 is connected at the meter point to the neutral and the neutral/earth concentric outer winding is taken to earth ( ground) via earth electrode someplace up the street by the Electric Co. Certain pass parrameters are required for Circuit breaker/ earth loop impedance and bus ral GFIC ( residual circuit device - here) opperation.

Other installations would be 4 wire 3 phase. 230 volts and 415 volts. 100amp generally for smaller 3 phase installations. Same parrameters apply.

For Construction Sites no earth is permitted via the supply. The site has to be electrically seperated from electricaal scource and other earths(grounds) A dedicated earth spike is installed to meet electrode resistance standards and a Residual Current Device is installed to break all poles of the supply on fault current. 30mA max. A further requirement is to have a 110V transformer to supply site equpment with the secondary center tapped tp 55 Volts. The RCD must also opperate at 55 Volts to earth fault at a max of 30mA,

Frank Doncaster England UK.


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## Joe Momma (Jan 23, 2007)

That is some neat looking stuff. Seems like they use a lot of plastic over there, although that residential panel looked pretty small (post #46 above), how many centimeters is that panel? And what mm is the wire size being used in that picture?


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## MDShunk (Jan 7, 2007)

Joe Momma said:


> That is some neat looking stuff. Seems like they use a lot of plastic over there,...


Square D made the "Trilliant" panel, which was all plastic, and was quite like the European panels. It was a miserable failure here in the US.


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## frank (Feb 6, 2007)

*Uk Dist Boards*

Hi Joe

First. JD is right. The SQ/D board was not succesfull here either.I think the board went out of production in 1975 or so. Square D make some very pretty boards at the moment. And very good quality too.

The MEM board you mentioned is 14 inches wide (280mm) and plastic as you noticed. Plastic boards are common for Domestic work where no conduit systems are installed and the board can be mounted on Dry Walll etc. There is another reason though. Some areas insist on domestic boards being plastic so as to protect against a metal cabinet becoming 'live' from the supply scource. If you wish to use a metal type you have to fit downstream of the unit a Residual Current device (GFIC) also in a pvc box between it and the meter.

The cables connecting the supply to the distribution unit (consumer unit) are 16mm square. Normal for a 100 amp supply. But if the cables go into a cavity as in the Meter Cabinet Pictures for a domestic situation then the cable sizes rise to 25mm Square. Temperature Coefficients and all that stuff.


Frank

Doncaster England


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