Breaker Box Wiring

[phibunmike]

phibunmike, under no circumstances should you use metal piping as an earth...even as a secondary earth. Earth 'potentials' can be dangerous, so only use the one earth...the main earth. Having more than one earth, especially at distances greater than 3 metres apart, can lead to 'earth potentials'. ONLY USE THE MAIN EARTH VIA A GPO OR VIA AN EARTH WIRE DIRECTLY CONNECTED TO THE MAIN EARTH BAR IN YOUR MAIN DISTRIBUTION BOARD. This only applies if you choose to use an earth that is NOT a stake driven into the ground. Residential earthing should always be via an earth stake driven into the ground.

Cheers,

Rob.

Thanks again.

There is some confusion here (at least for me ). I do not intend using the metal pipes as earth - but I had the intention of earthing the metal pipes; is this wrong ?

(The metal pipes are only a couple of metres in the bathroom from the water heater to the shower. All other pipes are PVC).

Edited February 13, 2006 by phibunmike

[Crossy]

There is some confusion here (at least for me ). I do not intend using the metal pipes as earth - but I had the intention of earthing the metal pipes; is this wrong ?

YES, DO earth the metal pipes to your ground bar in the dizzi box. What we are saying is do not earth TO a metal pipe, subtle difference

If you wade through the link I gave it also gives advice about how to use multiple earth rods including an over-the-top (for domestic anyway) ground ring system.

[elkangorito]

I must agree with crossy 80% on earthing metal pipes.

Back in the 1800's, Thomas Edison & Tesla (Tesla is the Father of electrical power distribution...not Edison) experienced problems with earthing systems. The problems were that people were getting zapped simply by walking over certain parts of ground. This directly relates to the earthing of metal piping. As a general rule, ALL metal piping of any description SHALL not be earthed. There are 2 reasons for this.

1) Earthing a metal pipe can create an 'earth potential' due to oxidisation of pipework & therefore create a hazard.

2) Earthing of metal pipework can create capacitance (stored electrical charge) also causing an electrical hazard.

Generally speaking, METAL PIPEWORK OF ANY DESCRIPTION SHOULD NOT BE EARTHED!!!! If an appliance is earthed by it's designated earthing point, this should be sufficient. I can understand why you would want to earth the shower pipework but there is no need for this, especially when it can create more problems for you. Having been a radio technician in the RAAF, I can tell you that earthing 2 sides of a conductor can create problems. This is all to do with 'current flow' & 'resistance' (impedance, for AC circuits).

I state again, DO NOT EARTH ANY METAL PIPEWORK!!! If appliances/equipment is earthed correctly as per their designated earthing points, you should not have any problems.

Earthing is not as easy as it seems. Many other factors come into play that are not known to the young player.

If you have followed the MEN system of earthing, there is no need whatsoever to earth metal pipework. Please do not earth this pipework. Use your appliance/equipment earthing points only.

Edited February 14, 2006 by elkangorito

[Crossy]

I must agree with crossy 80% on earthing metal pipes.

Back in the 1800's, Thomas Edison & Tesla (Tesla is the Father of electrical power distribution...not Edison) experienced problems with earthing systems. The problems were that people were getting zapped simply by walking over certain parts of ground. This directly relates to the earthing of metal piping. As a general rule, ALL metal piping of any description SHALL not be earthed. There are 2 reasons for this.

1) Earthing a metal pipe can create an 'earth potential' due to oxidisation of pipework & therefore create a hazard.

2) Earthing of metal pipework can create capacitance (stored electrical charge) also causing an electrical hazard.

Generally speaking, METAL PIPEWORK OF ANY DESCRIPTION SHOULD NOT BE EARTHED!!!!

Agreed true, but Mike's pipe is isolated from ground by his PVC inlet pipe, just goes between the heater and the shower, can't hurt to ground it.

I thought the Tesla / Edison problem was caused by people earthing TO metal pipework and using the pipe as the return in a single-wire ground return feed system, could be wrong though

At least we're not diametrically opposed on this one :D

[elkangorito]

Crossy, the fact that his pipework is separated from the electrical circuit via a PVC connection is EXACTLY the reason why it should not be earthed. This is the classic way an 'earth potential' can be created...especially if there is any resistance to the the main earth from the separately earthed pipework.

His pipework is not a personal threat unless it is electrically connected to the electrical system (via an earth for example).

I must insist that this pipework NOT be earthed.

[elkangorito]

In this situation, the metal pipework should not be earthed as the appliance earth is adequate. If this was a gas appliance, earthing the metal pipework would present a great hazard. If it is a hot water heater, earthing the metallic heater is more than sufficient for personal protection. DO NOT EARTH ANY METAL PIPEWORK.

[Crossy]

Crossy, the fact that his pipework is separated from the electrical circuit via a PVC connection is EXACTLY the reason why it should not be earthed. This is the classic way an 'earth potential' can be created...especially if there is any resistance to the the main earth from the separately earthed pipework.

His pipework is not a personal threat unless it is electrically connected to the electrical system (via an earth for example).

I must insist that this pipework NOT be earthed.

Well, assuming that the water heater is correctly grounded there is really no advantage to adding an additional wire to the pipe (since it's linked to the heater by the pipe joint). Point conceded

I do admit that I wouldn't consider any ground in addition to the water heater in the UK, seems that the generally lax attitude to grounding in LoS has made me paranoid.

I must say that it is a breath of fresh air to have a discussion on electrical issues with someone who actually KNOWS what he is talking about. Peace to all sparkies (god I hate that term).

[Crossy]

All this talk of to ground or not to ground metal pipework leads to an interesting point.

In the UK (at least whilst I was doing electrical installations) it was REQUIRED practice that both water and gas pipes were connected to the mains ground IF (and only if) they had a PLASTIC incoming pipe. I'll try and find a reference to this practice.

I don't recall this practice being recinded recently, but as I've said before, it's been a long time since I did any domestic wiring on a professional basis.

EDIT. Grounding is such a complex subject thet the IEE is holding a one day seminar on the subject :-

http://www.iee.org/oncomms/pn/betnet/Earth...stallations.cfm

Edited February 14, 2006 by Crossy

[elkangorito]

All this talk of to ground or not to ground metal pipework leads to an interesting point.

In the UK (at least whilst I was doing electrical installations) it was REQUIRED practice that both water and gas pipes were connected to the mains ground IF (and only if) they had a PLASTIC incoming pipe. I'll try and find a reference to this practice.

I don't recall this practice being recinded recently, but as I've said before, it's been a long time since I did any domestic wiring on a professional basis.

Hi Crossy,

It's not often that I can speak with an equal on this subject. As you say, 'it is a breath of fresh air'.

The only reason I can think that a PVC pipe would be earthed, is for static electricity reasons.

Anyway, many people have electricity ar*e about face...they think that the active is the most important & dangerous, the neutral next & lastly, the earth. As you & I know, the earth conductor is the most important, followed by the neutral & then the active.

By the way, for those wanting to know cable sizes, for a standard 80/100 amp consumer mains, a minimum 6 millimetres squared main earth cable is required (single phase). For multi-phase systems, a main earth cable of half the current rating of the largest active conductor is required.

Edited February 14, 2006 by elkangorito

[Crossy]

Anyway, many people have electricity ar*e about face...they think that the active is the most important & dangerous, the neutral next & lastly, the earth. As you & I know, the earth conductor is the most important, followed by the neutral & then the active.

This is probably the single most important point that has been made on this thread!!!!!

Been poking around the members area of the IEE website (yes I am a member), found a CD ROM copy of the IEE Wiring Regulations 16th Edition (The Bible), useful I thought, then I saw the price 395 POUNDS!!!

Edited February 14, 2006 by Crossy

[phibunmike]

Anyway, many people have electricity ar*e about face...they think that the active is the most important & dangerous, the neutral next & lastly, the earth. As you & I know, the earth conductor is the most important, followed by the neutral & then the active.

This is probably the single most important point that has been made on this thread!!!!!

Been poking around the members area of the IEE website (yes I am a member), found a CD ROM copy of the IEE Wiring Regulations 16th Edition (The Bible), useful I thought, then I saw the price 395 POUNDS!!!

Well thanks again to you both (Crossy and Elkangorito) for all your knowledgeable input.

Elkangorito, you might be interested to know that I have a "high power" mains supply of 20A, compared to the typical 3A / 5A of my neighbours !!! No 80/100 around here !!

[Crossy]

You are most definately welcome

Any other questions as to what to do with your whole 20 Amps, you know where to ask.

My place in Italy (central Rome) had a 15A incoming breaker, with an electric water heater, aircon, washer, kettle, toaster (all rated at 8-10A each) it needed some very careful juggling "PLEASE don't put the kettle on whilst I'm in the shower dear" to avoid trips, I'm sure you know what I mean.

[elkangorito]

Anyway, many people have electricity ar*e about face...they think that the active is the most important & dangerous, the neutral next & lastly, the earth. As you & I know, the earth conductor is the most important, followed by the neutral & then the active.

This is probably the single most important point that has been made on this thread!!!!!

Been poking around the members area of the IEE website (yes I am a member), found a CD ROM copy of the IEE Wiring Regulations 16th Edition (The Bible), useful I thought, then I saw the price 395 POUNDS!!!

Well thanks again to you both (Crossy and Elkangorito) for all your knowledgeable input.

Elkangorito, you might be interested to know that I have a "high power" mains supply of 20A, compared to the typical 3A / 5A of my neighbours !!! No 80/100 around here !!

phibunmike, can you please tell me why you think that your Consumer Mains is 20 amp? Is it 3 phase or single phase? 3 to 5 amps is not enough to run a fridge & a telly.

[phibunmike]

phibunmike, can you please tell me why you think that your Consumer Mains is 20 amp? Is it 3 phase or single phase? 3 to 5 amps is not enough to run a fridge & a telly.

Hi, well let me first state that when I got power all the conversation was in Lao so I couldn't follow it - I am going by what my wife and neighbours tell me.

When you sign up for power you can select (at different cost) how many amps supply you want. I went for the biggest, which was 20A. My fan almost stops when someone is in the shower - it is quite a handy way of telling when the shower is occupied

In the village, my father in law has (he tells me) either 3A or 5A. They have a small fridge and a telly, a rice cooker, a couple of fans, a water pump and about 4 fluorescent tubes.

If the TV is, say, 300W and the fridge, say, 400W, then about 200W of lights etc., that would be, say, 1000W, or 4A. So if my estimates are reasonable they probably have a 5A not 3A supply...

Edit> forgot to mention, single phase.

Edited February 16, 2006 by phibunmike

[elkangorito]

phibunmike, can you please tell me why you think that your Consumer Mains is 20 amp? Is it 3 phase or single phase? 3 to 5 amps is not enough to run a fridge & a telly.

Hi, well let me first state that when I got power all the conversation was in Lao so I couldn't follow it - I am going by what my wife and neighbours tell me.

When you sign up for power you can select (at different cost) how many amps supply you want. I went for the biggest, which was 20A. My fan almost stops when someone is in the shower - it is quite a handy way of telling when the shower is occupied

In the village, my father in law has (he tells me) either 3A or 5A. They have a small fridge and a telly, a rice cooker, a couple of fans, a water pump and about 4 fluorescent tubes.

If the TV is, say, 300W and the fridge, say, 400W, then about 200W of lights etc., that would be, say, 1000W, or 4A. So if my estimates are reasonable they probably have a 5A not 3A supply...

Edit> forgot to mention, single phase.

Hi Mike, if I were you, I'd opt for a 10 amp 3 phase supply (if possible) as opposed to a 20 amp single phase supply. The reason for this is that you will have 3 lots of single phase, each capable of delivering 10 amps. You must then try to equally divide the residential load over the 3 phases so as not to overload 1 of the phases. Not only this but it also gives you the option of using 3 phase equipment, which is about 40 to 60% more efficient than single phase equipment (only really applies to inductive equipment like motors, welders etc).

Have you considered solar powered hot water? Very efficient & the cost savings are substantial. If you wish to try this, always opt for stored hot water ('Solarhart' Australia). If you have incandescent lighting, change to fluorescent (electronic ballast with XL Triphosphor tubes or the newer type EMR lighting). Upgrading your lighting will reduce your electrical load & will save you money (less globe changes).

Edited February 16, 2006 by elkangorito

[chownah]

One way to get more electricity is to build another house on your property. I'm building a work shop on my property and in the future I'll install a toilet and a shower and call it a house....get a house book for it and have a seperate electrical service for it....voila...twice the electricity!!.

[elkangorito]

One way to get more electricity is to build another house on your property. I'm building a work shop on my property and in the future I'll install a toilet and a shower and call it a house....get a house book for it and have a seperate electrical service for it....voila...twice the electricity!!.

Unfortunately chownah, this is not safe unless you are getting the power for both installations from the one supply. Consequently, randomly sharing power over 2 installations from 2 power sources, is very dangerous with regard to earthing etc. I hope you do not plan on doing this.

[chownah]

One way to get more electricity is to build another house on your property. I'm building a work shop on my property and in the future I'll install a toilet and a shower and call it a house....get a house book for it and have a seperate electrical service for it....voila...twice the electricity!!.

Unfortunately chownah, this is not safe unless you are getting the power for both installations from the one supply. Consequently, randomly sharing power over 2 installations from 2 power sources, is very dangerous with regard to earthing etc. I hope you do not plan on doing this.

I am absolutely going to do this. It's all single phase 220 here and the two main panels will be hooked up to the same supply lines only one will come off of the supply lines at the next pole down. The hot and neutrals will be the same...they'll each have their own grounds. None of my outlets are grounded now and I don't plan on running any ground wires to any of the outlets I establish from the new box.

I don't see what the problem would be...can you explain some problem with this?

Chownah

[Crossy]

I am absolutely going to do this. It's all single phase 220 here and the two main panels will be hooked up to the same supply lines only one will come off of the supply lines at the next pole down. The hot and neutrals will be the same...they'll each have their own grounds. None of my outlets are grounded now and I don't plan on running any ground wires to any of the outlets I establish from the new box.

I don't see what the problem would be...can you explain some problem with this?

Chownah

If it's as you describe I doubt you will have any serious safety issues although it's not the way I would do it. A bigger supply is the proper solution. I assume that you've investigated ugrading and come up empty.

Watch out for potentials between your two neutral connections if you have many users down stream from you. Bonding the incoming neutrals together may be an option but I'm not sure of the legality of linking the two supplies like that.

If the two supplies are used in separate buildings (you said it was to be a workshop) there is no issue.

Edited February 19, 2006 by Crossy

[chownah]

Crossy,

Thanks for the reply. It seems to me that as long as every circuit which I run has the neutral and hot from the same panel I don't see what possible problems could arise. The only possible complication that I could envision is if I had my TV plugged into a line from Service #1 and my DVD player plugged into Service #2 and then having a signal wire between the two. This in effect would be a possible coupling of the two services...but...I believe that input and output signal jacks are extremely well isolated from the main power input.....initially by power conditioners and then by power limiters (often zener diodes to ground) at various stages of signal processing. If there is a leak of current to the chassis of both the TV and the DVD player then in theory you could have a voltage difference between them but you could have this even if they were both plugged into the same outlet but with the plarity of the plugs reversed.

Anyway I'm just hoping that if someone sees a problem with this (like elkangorito) that they will post so that I can either avoid the problem or cancel my plans.

Thanks again,

Chownah

Edited February 19, 2006 by chownah

[Crossy]

Chownah.

Apply common sense

Try to have all your outlets in each building from one service, if not possible then at least all the outlets in each room.

Maybe use one service to run permanently connected items like the aircon, water heater etc. to assist with the above.

I would seriously consider installing grounded outlets.

[elkangorito]

Chownah, perhaps you could whip up a drawing of your proposal using the Windows program called "Paint" & then attach it to your next post. It'll be easier for me & others to comment upon than it is to try to imagine what you intend to do.

[lopburi3]

phibunmike, can you please tell me why you think that your Consumer Mains is 20 amp? Is it 3 phase or single phase? 3 to 5 amps is not enough to run a fridge & a telly.

Electrical service is quoted by meter ratings here of 5/15 amp (normal upcountry home) or 15/45 amp (normal airconditioned city home) or higher service. When people speak of what they have it is the lower figure on the meter. Almost no 3 phase service is used (except for some expats and seriously rich Thai). I have never seen a meter with 20 amp rating here myself. The 5 upcountry and 15 in the city are normal.

Perhaps a 20 amp breaker is being used inside his home if he is running the 5/15 meter?

[chownah]

Chownah, perhaps you could whip up a drawing of your proposal using the Windows program called "Paint" & then attach it to your next post. It'll be easier for me & others to comment upon than it is to try to imagine what you intend to do.

No need for a drawing...its really simple. I have one main panel already. It has two wires coming to it..a neutral and a hot. I'll get another main panel installed when my shop is finished. It will have two wires coming to it...a neutral and a hot. The drops from the street that feed the two meters which supply the two panels will be about 30 metres apart on the same power lines which run along the street.....both panels will receive their hot wire from the same power line and both of the panels will receive their neutral from the same power line. I will run circuits to where ever from each panel but of course making sure that all the wiring to each individual outlet or each individual hard wired appliance comes from the same panel.....no circuit will have a hot from one panel and a neutral from the other panel....this is very simple, I think.

I'll give you a worst case scenerio so you can tell me what the problems might be. Perhaps I'll have two outlets right next to each other with one having all its wires coming from one panel and one having all its wires coming from the other panel. What possible problems can you see coming from this arrangement?

Chownah

P.S. I'll consider having a running ground with some circuits....and once again I would be sure that the running ground for a circuit would go to the main panel which supplies the hot and the neutral wires too.....and each main panel will have its ground electrode located right at the panel...the distance between the panels is about 30 metres.

Chownah

It seems to me that if you always wire a circuit with only wires from one panel then there is no problem involved....but perhaps I'm wrong....but I don't see what the problem would be.

[phibunmike]

phibunmike, can you please tell me why you think that your Consumer Mains is 20 amp? Is it 3 phase or single phase? 3 to 5 amps is not enough to run a fridge & a telly.

Electrical service is quoted by meter ratings here of 5/15 amp (normal upcountry home) or 15/45 amp (normal airconditioned city home) or higher service. When people speak of what they have it is the lower figure on the meter. Almost no 3 phase service is used (except for some expats and seriously rich Thai). I have never seen a meter with 20 amp rating here myself. The 5 upcountry and 15 in the city are normal.

Perhaps a 20 amp breaker is being used inside his home if he is running the 5/15 meter?

Hi Lopburi,

I was referring to the supply, but have no hard evidence - I have just been told that's what I have. Tomorrow I will take a walk down the road and have a look at what it says on the meter.

Crossy and Elkangorito - PLEASE DO NOT READ THE NEXT PARAGRAPH

There are no poles near my house yet, so my meter is on a pole about 500m away and I have strung wires on bamboo poles down the road to my place. This is one reason my lights dim when the water pump runs - I am sure it will be much better once the electricity company have run proper poles and cable down my road

[Crossy]

Crossy and Elkangorito - PLEASE DO NOT READ THE NEXT PARAGRAPH

There are no poles near my house yet, so my meter is on a pole about 500m away and I have strung wires on bamboo poles down the road to my place. This is one reason my lights dim when the water pump runs - I am sure it will be much better once the electricity company have run proper poles and cable down my road.

Ah, but you can guarantee that the 'inspector' from the electric company will arrive to survey the new poles, find 'adequate' poles installed and go home, 'no additional installation work required'

Might be time to invest in some fatter wire.

[elkangorito]

Oh dear!! What have we here?

Ok Chownah, your idea is ok but how it is implemented, is another matter.

I'm assuming, from what you have said, that you will have 2 "SEPARATELY METERED SUPPLIES". If this is incorrect, please say so. Allow me to explain...if you have 2 separate supplies coming into your property, they SHOULD be treated as 2 separate installations with individual meters thus you will receive 2 power bills...one for each installation. Is this correct?

If not, then the power to your NEW installation MUST come from your Main Distribution Board as a "sub circuit".

Also, IF the new installation is a separate supply, then an MEN link MUST be installed in this new installation.

Further, as Crossy said, if you experience dimming of lights etc when motors cut in, then you need "fatter" cables. This is a direct consequence of voltage drop due to long distance of cables with maximum current demand. Basically, this means that the cable size from the transformer is not big enough for your requirements. As an example & contrary to Lopburi's ideas, 3 phase supply is available if you give a reason. A mate of my'n got 3 phase supply because he was using 3 phase motors for a fish/prawn farm. The supply authority installed a 3 phase 50mm squared (aluminium) supply as a result of his request. I dare say that he had to prove his requirement. Nonetheless, he has a large amount of power at his disposal. I do not know anything about this 5/15 or 15/45 amp meter stuff. What the he_l does it mean? Normally, supply is indicated by demand current. ie an 80 amp supply is fed by minimum 16mm squared copper aerial conductors. The kwH meter reflects the cable size. In Thailand, it may be different & until someone can give me some diffinitive information about this, I will not think otherwise. Kilowatt hour meters are rated for their "through put" current, since they are in series with the line current. So, what does 5/15 mean? By the way, unless this can be answered with "provable" information, I will not believe it.

With regard to "poles", they are not the issue. The issue is cable size. Bamboo is ok. It just degrades very quickly due to ingress of ants etc. If they have appropritae electrical insulators upon them, all is ok untill nature quickly degrades them.

Anyway, if you plan to foolishly apply an earthless installation, GOOD LUCK!!! I will never endorse this.

Just going back to a previous statement, YOU MUST HAVE AN MEN SYSTEM INSTALLED AS A "PRIMARY" SAFETY SYSTEM. Without this, you & your family are at a much greater risk of electrocution. Don't forget that the SECONDARY SYSTEM is an RCD (earth leakage protection device). If you've read the previous posts, you will know the dangers of relying totally upon the "RCD only" system. I will be happy to reiterate should you have forgotten.

EATHING IS THE MOST IMPORTANT THING YOU MUST DO. THIS INCLUDES ALL METAL CLAD APPLIANCES. DOUBLE INSULATED APPLIANCES LIKE TV'S ARE NOT A PROBLEM. YOU MUST USE 3 PIN POWER OUTLETS. IF IN DOUBT, EARTH IT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[lopburi3]

As an example & contrary to Lopburi's ideas, 3 phase supply is available if you give a reason.

I never said it was not available. I said it is not commonly used for normal homes here.

[elkangorito]

phibunmike, can you please tell me why you think that your Consumer Mains is 20 amp? Is it 3 phase or single phase? 3 to 5 amps is not enough to run a fridge & a telly.

Electrical service is quoted by meter ratings here of 5/15 amp (normal upcountry home) or 15/45 amp (normal airconditioned city home) or higher service. When people speak of what they have it is the lower figure on the meter. Almost no 3 phase service is used (except for some expats and seriously rich Thai). I have never seen a meter with 20 amp rating here myself. The 5 upcountry and 15 in the city are normal.

Perhaps a 20 amp breaker is being used inside his home if he is running the 5/15 meter?

My dear Lopburi,

What you said, is above. Somewhat different & obscure I think.

[lopburi3]

And that is what I wrote - we were talking home use and 3 phase is seldom used except by some expats (normally running electric kitchens) and in the homes to the top few percentage of Thai. What I provided is correct information. Are you really reading my post as saying 3 phase is not available? Or is this a language difference? In my usage not used does not mean not available.