Electrical Tutorials -Safe Electricity Without a Ground

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Electrical Tutorials -Safe Electricity Without a Ground

Postby Itchy » Mon Aug 29, 2005 6:08 pm

Perhaps the most misunderstood electrical topic of all.

It might run contrary to everything you have ever heard about electricity but it IS possible to have a SAFE electrical installation without a "Ground" (Earth) connection in the house.

Here's how and why.
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nice one

Postby robint » Mon Aug 29, 2005 6:38 pm

:D

the RCBO is the latest kit, its expensive (ca 100 quid in uk) compared to the standard rcd plus mcb (ca 10 quid)

So what kind of kit is actually available in your local electrical shop in LOS

Not and RCBO I suspect :D
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Postby Itchy » Mon Aug 29, 2005 7:00 pm

RCBOs are widely availble in Thailand.

Expensive? I don't think so given the improvement in safety they provide, they are cheap. Measured against the cost of a house construction they are a tiny fraction of the cost.
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RCBO with faulty computer

Postby dozer » Mon Aug 29, 2005 9:07 pm

I'm wondering how this would work in the case of my faulty computer. I assume now after reading previous posts, the computer has a problem because in a non-grounded environment I get shocked and in a grounded environment there is no shock.

In non grounded environment with the RCBO how would it work if I wanted to use my computer as is. Would I have to ground the computer itself and then everything would work OK?
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shocking

Postby robint » Tue Aug 30, 2005 6:33 pm

:D

As I am sure Itchy is itching to tell you

if you were to use an RCD on your computer supply, it would probably trip out each time you touched your computer - try it and tell us your results. The National RCD is ca 400 Baht and has the same casing pattern as the National "breaker" fyi

ps it would be helpful for others here if you could take a photo of both types and show it on this post, i cant do this just now cos im in UK

The answer to the above is to get an earth rod, 1.5m is normally enough. Drive it into the ground (near the cess pit is good), and then run a 6mm earth up to your computer.

btw, a square pin extension lead with 4 sockets and a REAL surge protector, is a good investment for computer gear. You can then have your own local 3 pin system. I also use a 500W standby power supply in case of power outs which happens quite often. All this kit is available cheaply in IT City South Rd pattaya

The above has worked for me without any problem for 3 years now

leaky computers is a common problem. in my local tech they have foun over 200 machines with this problem.

I am meeting with the Chief tech soon to discuss this phenomenon. It only becomes noticeable if the earth wire is not grounded. Needless to say this is a shocking discovery and in the light of the latest regulations require PAT testing (portable appliance testing) its very embarrassing. WOTODO

we could have a whole separate topic on computer hardware stuff :)
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Re: shocking

Postby Attila » Tue Aug 30, 2005 8:01 pm

robint wrote:The answer to the above is to get an earth rod, 1.5m is normally enough. Drive it into the ground (near the cess pit is good), and then run a 6mm earth up to your computer.

btw, a square pin extension lead with 4 sockets and a REAL surge protector, is a good investment for computer gear. You can then have your own local 3 pin system.


So, basically what you are saying, robitn, is to use a 3 pin / 3 wire system, with one wire for the ground, at the end connected to an earth rod, for your PC.

Isn't it the idea behind that third wire in a 3 wire cabling that you do not have a separate earth cable from your PC (or whatever appliance) hanging around, waiting for you or your toddler to fall over it, but all safe and hidden in the walls?

If you have several PCs, of course this applies to every PC.

If you move the PCs around, of course this applies to every potential plug to connect a PC.

So to avoid a mess with separate earth cables whereever you happen to connect a PC (or similar device), waiting for you to tumble over them, you might as well get all plugs installed with a 3 pin 3 wire cabling, and of course a proper connection to an earth rod, as you describe it.

Which is the opposite of what you said until now so many times: "you can't use a 3 wire system" :wink:

I'm happy to see that you changed your mind and that you support a 3 wire cabling now (at least for the PC connection).

robint wrote:The above has worked for me without any problem for 3 years now


Hmm, then why telling us to use 2 wire cabling only even for the PCs?

robint wrote:leaky computers is a common problem. in my local tech they have foun over 200 machines with this problem.


Well, all computers connected without earth to a 2 pin plug I used so far - and that's quite a few - , did happily zap when touching the case and the ground, such as a marble floor, without rubber shoes.

This is the case for desktop PCs and notebooks with a 3 wire cable and plug. The only PCs which did not show that behavior had been notebooks which come with a 2 pin plug / 2 wire cable only :cry:

It is a nice effect, you wake up again and can continue working with full concentration :wink:

I tend to assume that this is not a fault, but a design feature (be it good or bad).
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Postby the limey » Tue Aug 30, 2005 8:25 pm

A good idea would be to get your poxy pcs fixed so they didn't electricute you, <Edited by moderator - inappropriate language or off topic> , when it's fixed think about earths< i got to admit that robin t is right and a lot of this stuff by itchy is wasted on you lot and probably quite dangerous, you all seem to think the problem with a dodgy machine is earthing it, IT IS NOT, fix the machine, a machine ie like a shower is a life threatening situation, you fix it or buy a new one, yes you also have an earth aswell, but fix the <Edited by moderator - inappropriate language or off topic> machine that is electicuting you first.

as robint said, it's best to go back to basics so ppl understand...

you lot aint gonna be setting up 3 phase wiring this year....

<This post was edited by moderator due to inappropriate language or off topic content>
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blimey

Postby robint » Tue Aug 30, 2005 8:53 pm

:D

hi limey, glad to see your back with some down to earth (sorry) comments

i feel like a voice in the wilderness here

Personally I am puzzled by this pc zapping problem and I havent taken the time out to investigate why it happens, but its very common, so buying a new pc may give you the same result, but I am going to see someone in a Tech college soon and will report back

In the land of the blind the oneyed man is king :D
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Postby the limey » Tue Aug 30, 2005 8:55 pm

I apologise for my previous post, but learning to be a sparky aint gonna happen over 20 tutorials, it aint gonna happen over 50 tutorials, being a sparky is a trade and takes a few years,Ive been in building for over 20 years now and yes we run all our own cables, but everytime I get a sparky in to do the final checks and connections, This is not something the normal house holder should do, same as you wouldn't build a towerblock.
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Postby Attila » Tue Aug 30, 2005 9:08 pm

<Edited by moderator - off topic>

the limey wrote:fix the<Edited by moderator - inappropriate language or off topic> problem, when it's fixed think about earths< i got to admit that robin t is right and a lot of this stuff by itchy is wasted on you lot and probably quite dangerous, you all seem to think the problem with a dodgy machine is earthing it, IT IS NOT, fix the machine, a machine ie like a shower is a life threatening situation, you fix it or buy a new one, yes you also have an earth aswell, but fix the <Edited by moderator - inappropriate language or off topic> machine that is electicuting you first.


Of course fixing anything broken is the correct action. No discussion about that.

There is however a problem, and you might not be aware of it:

What do you tell compaq (replace by whatever you want) when they sell you a PC / notebook which zaps you when you plug it in an unearthed plug?

And what do you say when all their PCs and even the notebooks do that? All faulty? Repair it? Right!

This is not realistic, not at all.

Even robitn did find 200 of these "faulty" PCs in his kingdom. Now what does that tell you?

To me, it means, well, earth that thing!

If you know a shop which can repair it, tell us. Preferably one which can do so without voiding the warranty.

the limey wrote:you lot aint gonna be setting up 3 phase wiring this year....


Wanna bet?

the limey wrote:... a lot of this stuff by itchy is wasted on you lot and probably quite dangerous, ...


Well, it was Itchy to show us how to make a 2 wire installation more safe. I would say that that can get qualified as the opposite of dangerous, can't it.

Others in the knowledge did not share this important advice with us :cry:
Last edited by Attila on Thu Sep 01, 2005 12:28 am, edited 1 time in total.
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Postby the limey » Tue Aug 30, 2005 9:17 pm

Wattana opposite foodland fixes pcs that eletricute you, it's real cheap, the only thing made to electocute ppl is a stun gun, if you get shocks off of something then get it fixed, unless it's a stun gun, pcs etc are not made to give electric shocks, they are made as pcs, can you understand this yet?
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Postby Itchy » Wed Aug 31, 2005 1:22 pm

Can we understand that I shall continue to post tutorials on a range of electrical subjects, unless asked not to do so by the site owner/moderator.

If you object to information on this subject being provided, either contact the Moderator with your objections or don't bother reading them.
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Postby the limey » Wed Aug 31, 2005 5:15 pm

Itchy, I have nothing against your tutorials, I have to admit that I haven't read any of them but that is irrelevant, Knowledge is a great thing and sharing knowledge is great, but could you please explain to posters that pcs or whatever are not designed to electrocute people, if an electrical appliance is zapping you then fix the appliance and then make it safe by grounding it, do not just ground it, the problem may get worse and then one day the ground wire may break, niether of my pcs are grounded and I can quite happily take them apart while they are on, many other peoples pcs I have used they have a mat by the desk chair, they then tell you that you have to put your feet on the mat so you do not get electrocuted, that is a ridiculous and dangerous way to live....
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Pictures, Prices and Amperages

Postby jazzman » Wed Feb 28, 2007 8:51 am

There are now pictures, prices, and where to buy these Minature Circuit Breakers, their housing and the RCBO (Residual Current Detector/Breaker, aka Earth leakage Breaker) on this thread - together with everything else you need to equip a house, with up-to-date prices:

http://coolthaihouse.com/cthpics/thumbnails.php?album=10

Contrary to common belief, this equipment is NOT expensive at all, nowhere near the GBP 100.00 cited - not even half that :!:
Last edited by jazzman on Sat Feb 07, 2009 4:12 pm, edited 1 time in total.
How to build a $20,000 / £14,000 house and a $???? MOTEL Updated 21 March 09 - with BOQ and costs
Don't let this happen in YOUR house.
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Postby rigpig.sparky » Wed Jan 30, 2008 12:45 am

You guys crack me up !!!
Anyway I thought I'd put my 2 cents in and shake up the pot, it's always good for a laugh !!
OK zapping PC's, Don't know what causes it and yes it would be nice to fix it. Could it just be eddy currents from the transformer in the switching power supply. Maybe its just the nature of the beast after all an incolloy heating element even when it is brand new will "leak" to earth and the only thing I know of to TRY to fix it is turn the thing on and that won't always completely clear the fault. They are the only thing in Australia now you don't have to put on an earth leakage breaker. For those of you who don't know what an incolloy element is its a coil of resistive wire (usually a tungsten alloy) inside a metal sheath (which is earthed) surrounded by an insulating powder. Yep the one thats probably in your stove !!! What about that new fridge an electric motor immersed in an oil filled case when it gets a bit old and hot whats gonna happen. Will it kill you I doubt it if the thing is earthed correctly and it is not pulling enough current to take out the breaker..... However if it does go down enough the breaker will trip. Things are built down to a price not up to a standard and if there are standards all of the gear thats not up to scratch will end up in the country with the lowest (if any) standards. Can ya think of anywhere..... I doubt if trying to get manufacturers of new PC's (and I've experienced this with ones from overseas as well of Thailand) is gonna work. They will just tell you to buy another brand and guess what you will run out of brands. The bits are all farmed out anyway and probably come from the same factories in China brand name or not ! Earthing will make it safe Whilst Ichy's advice on 2 wire systems is sound and if you can't practically run an earth do it it will save your life However even if you use RCBO's you should have an earth anyway. Itchy are you sure that all of these things are double pole and that the neutral connection is not just there to provide the out of balance sensing ? All of the ones I have seen have the active and neutral connections marked on them so polarity must have some bearing on it, I'm not sure but I will check next time I get the chance. The active should always be the one that is disconnected from the supply as you know. People everything that could become live should be earthed end of story However earthing is not just a matter of running a wire to an earth stake it should be done properly by someone who knows what they are doing (LOL in LOS). I have started a thread on this subject and I welcome your feed back. Earthing the PC will not fix it but i iterate again IT WILL MAKE IT SAFE. Oh and you probably wont be able to use the computer if you have RCBO's installed , if the thing is earthed properly it will probably keep tripping out if its not earthed correctly it will only trip out when you touch it (you are the earth) :? :shock: :wink:
That should put the cat amongst the pigeons
Tony
Whats black and crisp and hangs off the ceiling ?
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