More bonding.

[Geoffsd]

Hi,

My name is Incognito. I have hacked Geoff's pc because I am not registered on the forum.

I have to decide whether supplementary bonding is required in a bathroom where I'm working.
Horror of horrors, there is no RCD on the lighting circuit which is the only circuit in the room.

Actually, it's a very small flat and the water and gas services enter in a cupboard on the other side of the bathroom wall.
This cupboard actually houses the consumer unit as well.
The main bond obviously runs from the water and gas pipes to the consumer unit.

The water pipe immediately returns into the floorboards and runs to the bathroom and farther to the boiler.
Under the bathroom floor the cold supplies the basin, bath and w.c.
The hot returns from the boiler in plastic under the floor where it connects to copper to supply the basin and bath.

The light cpc is only three metres from the cu (it's 1.5mm² which seems to be the fashion) and so has a resistance of 36.3mΩ (0.0363Ω).
The farthest water pipe is also three metres from the supply and so has a resistance including the main bond of 2mΩ (0.002Ω) to the MET.
So, a total of only 38.3mΩ (0.0383Ω)

I think I should install supplementary bonding from the light circuit to the w.c. water pipe.
However, the bathroom is fully tiled so it would be awful to have to channel the concrete ceiling to get to the light cpc and then down the wall to the pipe.

I have heard that it is permissible to apply the supplementary bonding outside of the room so would it be acceptable to do it in the cupboard?
If it would, I could easily connect the cold pipe to the cpc there.

Wait a minute -


that would be just duplicating the main bond.

Do you think it would be alright to not apply this supplementary bond at all as it doesn't really seem to make any difference, does it?
After all, light to pipe resistance is only 0.0383Ω and with an Ia of only 30A that means the touch voltage would only be 30x0.0383 = 1.15V.
Even with a 50A shower it would only be 9.6V.

Do you think it would confuse people in the future if they don't see supplementary bonding and will they realise that the main bond is actually doing the job of supplementary as well?


Should I bond the three cold pipes in the bathroom? I could run the conductor along the pipe?

What about the plastic supplied hot pipes?

 

[happysteve]

Hi,
What about the plastic supplied hot pipes?

Yes, you should definitely bond these. Drill a hole in the pipes, run your CPC on the inside, then make good using sealant (chewing gum is fine). Running your cable on the inside of the plastic pipe also affords it mechanical protection - double-win!

 

[Plonker 3]

Who needs bonding, dont issue a cert and no one will know you have even been there.

 

[Geordie Spark]

This place is getting to be more like a bondage club with the passing of each day.

 

[happysteve]

This place is getting to be more like a bondage club with the passing of each day.

Yeah, maybe I should be a bit more specific in my signature exactly what I'm here to learn...

 

[Geordie Spark]

Yeah, maybe I should be a bit more specific in my signature exactly what I'm here to learn...

Aye well, never mind. I blame Tony for it mesel'.

 

[happysteve]

Aye well, never mind. I blame Tony for it mesel'.

I'm not brave enough to respond to this. It'd either get me a couple of "likes" or a newly ripped arsehole... in't worth it

 

[guest119]

Tony gets the blame for everything, at least tonight anyway.

Boydy

 

[Badged01]

Hi Incognito,

Welcome to the forum, you are going to learn lots on here!

Don't get carried away with all the calculation stuffy, real 'sparks' don't do that, its just confusing you and misleading you from what's really simple -- just follow the electrical regulations as you read them. You probably havent got a copy BS7671 yet so I can understand your confused. If you do get a copy have a good read, you'll learn loads about everything and there great for bedtime reading as well. Send you to sleep real quick. Infact when you get a copy quote the regulations to the customer if its a "chicky", she'll be really impressed with your electrical knowledge.

What you need to do here is just apply loads of thin "green'n'yellow" looking wiring (let you in on a trade secret, thats what they call supplementary bonding wire) to every little bit of metal you can see anywhere in the flat, can't go wrong then -- also guaranteed to impress your assessor too when you apply to join an approved Part 'P scheme' later! And don't worry about the plastic pipes, someone once told a friend of mines girlfriends uncle that the water inside it makes it like a metal pipe anyway. You will pick up more of this knowledge as you spend more time on the forum, dont worry if its all a bit too much for you to at the moment, you will understand it eventually.

And forget about all this main bonding stuff, you dont sound as if you're ready for that yet. What it does is definately overrated and so yesterday, RCD's are where it's at now! Anyways, just to give you a little bit of information as knowledge is power, it's just thicker "green'n'yellow" looking wire but doesn't do anything. Just costs you loads to put it onto the gas boiler pipes and the toilet pipes -- I reckon it should be a plumbers job anyway as those guys know so much more than 'sparkies'. You'll learn more about bonding stuffy type things from the more experienced 'sparks' on the forum as you progress throught your 5W course. I think they're great and I'm wanting to have some of their babies.


p.s. I think you might be better of in the electrical trainee part of the forum to start off, or even the DIY forum if you're still unsure of things. But the guys on here are great and will always help you out if they can ;-)

p.p.s. And keep away from that Geordie fella. You dont want to know what he thinks bonding is for ...... someone reckons whips and chains excite him.

 

[Geordie Spark]

I'm not brave enough to respond to this. It'd either get me a couple of "likes" or a newly ripped arsehole... in't worth it

Coward!

- - - Updated - - -

Tony gets the blame for everything, at least tonight anyway.

Boydy

It's what we keep him for.

 

[happysteve]

Coward!

Don't you worry, one day I'll grow a pair.

 

[Geoffsd]

Thank you Badger for all the useful advice.

Just one more thing -
Is my metal toilet an extraterrestrial-convulsive-part?

I've heard people saying it can give you a shock unless you connect it to the window frame.
Until this is done should I hover?

 

[Guest55]

The light cpc is only three metres from the cu (it's 1.5mm² which seems to be the fashion) and so has a resistance of 36.3mΩ (0.0363Ω).

what test equipment are you using that has a resolution to 4 decimal places ?

I think I should install supplementary bonding from the light circuit to the w.c. water pipe.
However, the bathroom is fully tiled so it would be awful to have to channel the concrete ceiling to get to the light cpc and then down the wall to the pipe.

sounds like it would be alot easier to just add rcd protection to the affected circuits than rip apart the bathroom to install supp bonding ??

 

[Geoffsd]

what test equipment are you using that has a resolution to 4 decimal places ?

Imaginary tape measure and real calculator.

sounds like it would be alot easier to just add rcd protection to the affected circuits than rip apart the bathroom to install supp bonding ??

That's a good idea but -

it isn't necessary to install SB as the measurements are low enough already.



Have you missed some irony?

 

[Guest55]

Have you missed some irony?

it appears so.

there again , i wasnt expecting someone whom usually projects a very experienced and knowledgable persona to start a daft fake sulky thread cos not everyone has the same opinion as him in another more interesting thread.

;-)

 

[Badged01]

......Have you missed some irony?

Its looks like it's got lost somewhere!

 

[Badged01]

.... i wasnt expecting someone whom usually projects a very experienced and knowledgable persona to start a daft fake sulky thread cos not everyone has the same opinion as him in another more interesting thread.

Never judge a book by its cover! Deep down inside could be a fun person waiting to escape and enjoy the banter ......

 

[Badged01]

Until this is done should I hover?

Hi Incognito,

I always recommend to clients that they rip out the toilet and leave a hole to straddle ---- saves all the hassle and arguements about should the toilet seat be left up or down in the house!

Been working effectively that way in Asia for centuries

 

[Scornio]

Geoffsd,

As soon as I read the original post I understood quite clearly the irony and humour intended; however this forum is quite clicky, if you haven't been accepted by the pack then humour like this just wouldn't be tolerated.

 

[Badged01]

As soon as I read the original post I understood quite clearly the irony and humour intended; however this forum is quite clicky, if you haven't been accepted by the pack then humour like this just wouldn't be tolerated.

Dont believe it, you dont have to be a member of any 'clique' to post and have fun on here provided you obey the forum rules, Im a casing point! Rhino skin does help though .........

But if you want to join any of the 'special' forums then fill your boots and enjoy the privledges

 

[SirKit Breaker]

Hi Incognito,

Welcome to the forum, you are going to learn lots on here!

Don't get carried away with all the calculation stuffy, real 'sparks' don't do that, its just confusing you and misleading you from what's really simple -- just follow the electrical regulations as you read them. You probably havent got a copy BS7671 yet so I can understand your confused. If you do get a copy have a good read, you'll learn loads about everything and there great for bedtime reading as well. Send you to sleep real quick. Infact when you get a copy quote the regulations to the customer if its a "chicky", she'll be really impressed with your electrical knowledge.

What you need to do here is just apply loads of thin "green'n'yellow" looking wiring (let you in on a trade secret, thats what they call supplementary bonding wire) to every little bit of metal you can see anywhere in the flat, can't go wrong then -- also guaranteed to impress your assessor too when you apply to join an approved Part 'P scheme' later! And don't worry about the plastic pipes, someone once told a friend of mines girlfriends uncle that the water inside it makes it like a metal pipe anyway. You will pick up more of this knowledge as you spend more time on the forum, dont worry if its all a bit too much for you to at the moment, you will understand it eventually.

And forget about all this main bonding stuff, you dont sound as if you're ready for that yet. What it does is definately overrated and so yesterday, RCD's are where it's at now! Anyways, just to give you a little bit of information as knowledge is power, it's just thicker "green'n'yellow" looking wire but doesn't do anything. Just costs you loads to put it onto the gas boiler pipes and the toilet pipes -- I reckon it should be a plumbers job anyway as those guys know so much more than 'sparkies'. You'll learn more about bonding stuffy type things from the more experienced 'sparks' on the forum as you progress throught your 5W course. I think they're great and I'm wanting to have some of their babies.


p.s. I think you might be better of in the electrical trainee part of the forum to start off, or even the DIY forum if you're still unsure of things. But the guys on here are great and will always help you out if they can ;-)

p.p.s. And keep away from that Geordie fella. You dont want to know what he thinks bonding is for ...... someone reckons whips and chains excite him.

Badged as usual has given solid advice, so read what he says and lear from it. the only thing i will add, and i am not getting into the bonding argument, would be to get yourself the On site guide, and read that before tackling the Regs book. The OSG is written for us thick electricians, and it has pictures in as well, so even better. The Regs book is full of nerdy things that is hard to understand and it is what the designers use.

Ignore the smart comments, you will get more help than pee taking so stick with it.


Cheers…………Howard

 

[Geoffsd]

Thanks to all,

I just thought a step by step (and humorous?) approach to the problem of the other thread would help people realise the actual situation that they were encountering and realise that a piece of 4mm g/y isn't going to improve already low-enough resistances.

 

[Geordie Spark]

Imaginary tape measure and real calculator.



That's a good idea but -

it isn't necessary to install SB as the measurements are low enough already.



Have you missed some irony?

A recent blood test I had showed I am borderline anaemic so I have been prescribed some iron capsules to replace the irony I have lost.

 

[guest119]

Did you mean borderline academic :biggrin5: ?
Too much iron and you will get rusty pants Geordie!


Boydy

 

[Geordie Spark]

Did you mean borderline academic :biggrin5: ?
Too much iron and you will get rusty pants Geordie!


Boydy

I already have those or at least I think it's rust .........

 

[Badged01]

I already have those or at least I think it's rust .........

If it comes out after a good rubbing on the washing dolly its not rust .....

 

[Geordie Spark]

If it comes out after a good rubbing on the washing dolly its not rust .....

I can afford to chuck them away now since Tidyboiler gave me half a dozen new pairs yesterday for my birthday.

Should keep me going for another 6 years or so.

 

[Badged01]

......Tidyboiler gave me half a dozen new pairs yesterday for my birthday.

Mine does the same. There's something women like about a man in his Y-fronts and string vest .... drives them wild with passion :tt1:

 

[Geordie Spark]

Mine does the same. There's something women like about a man in his Y-fronts and string vest .... drives them wild with passion :tt1:

30 seconds in ....... Auf Wiedersehen Pet - Oz's fantastic rdeam - YouTube

 

[tidyboiler]

I can afford to chuck them away now since Tidyboiler gave me half a dozen new pairs yesterday for my birthday.

Should keep me going for another 6 years or so.

Well I figured since you could chop wood with the old ones, they needed replacing! :dita:

 

[Geordie Spark]

Well I figured since you could chop wood with the old ones, they needed replacing! :dita:

Yes pet ..... thanks pet.