Size of shower cable

[Leesparkykent]

I wasn't Questioning baldsparkies competency, just the fact he provided this information to someone who doesn't have the ability to do basic cable size calculations other wise this thread wouldn't of been started in the 1st place. And for saying this information is readily available on the internet, let the OP find this information for himself and not spoon feed him possibly the wrong information.
This plumber would of likely seen the bit I highlighted in bold in my previous post and took it as gospel as it's just come straight from an electricians mouth/keyboard lol.

 

[Guest77]

I wasn't Questioning baldsparkies competency, just the fact he provided this information to someone who doesn't have the ability to do basic cable size calculations other wise this thread wouldn't of been started in the 1st place. And for saying this information is readily available on the internet, let the OP find this information for himself and not spoon feed him possibly the wrong information.
This plumber would of likely seen the the bit I highlighted in bold in my previous post and took it as gospel as it's just come straight from an electricians mouth/keyboard lol.

Well we were :biggrin:

 

[Doomed]

Dear oh dear,
Talk about making a mountain out of a mole hill.
The original poster could gleam the information he requires from any web search or forum he wishes to visit.
It takes a simple google search.
And maybe that's where the real problem lies because as we all know a little knowledge can sometimes be dangerous.
The OP as an example could easily have visited this;

Removed

And taken his info from there.
So in retrospect I was simply making the OP aware of the many variables required to ensure the install was safe and compliant.
6mm as said, will suffice in most instances for an 8.5kw shower
And from 8.5 to 10kw 10mm.
Once again the installation method and cable run along with other factors will dictate.
Safety is paramount and for that reason a qualified electrician is the sensible way forward.
And looking back that's exactly what I said.
So no I was not giving the OP the green light, I was simply making him aware that there is more to his question than he was aware of.
I pointed out that if he was unsure seek a qualified electrician.
Hardly a green light, and as a response certainly not a case of the blind leading the blind.
I am well aware of my level of competence, experience, and knowledge base.
Still learning actually as we all are.
We can have differences of opinion, and different levels of experience.
But I hold true to my belief that certain people on this forum have a very arrogant attitude, and as said come from the I know better than anyone else brigade.
We can all cross T's and dot I's looking for holes to pick in someone's comments, but that doesn't excuse rudeness or lack of respect.
We all come from different backgrounds and levels of experience.
Regardless of trade or profession there are decent people and there are silly billy's lol.
Its as simple as that, we are what we are fellas.:icon12:

Reading your link it says up to 8KW on 6mm, unlike your earlier statement.

 

[baldsparkies]

For what its worth these kind of posts are not just related to this forum.

Removed

In real world scenarios I have come across 8.5kw showers on a 4mm cable running for years with no sign of thermal damage whatsoever.
I am NOT condoning this in any way but it does happen.
Point taken on the 8kw scenario with regards to the links but real world can,often be very different to calculated values and what you see in BS7671 or the like.

As said in my first post, if in doubt get a qualified electrician.

That's it from me enough said, cus this could go on and on.

And for what its worth I am not disagreeing with your comments, just the bad attitude attached to some of them.

 

[Guest77]

For what its worth these kind of posts are not just related to this forum.

Removed

In real world scenarios I have come across 8.5kw showers on a 4mm cable running for years with no sign of thermal damage whatsoever.
I am NOT condoning this in any way but it does happen.
Point taken on the 8kw scenario with regards to the links but real world can,often be very different to calculated values and what you see in BS7671 or the like.

As said in my first post, if in doubt get a qualified electrician.

That's it from me enough said, cus this could go on and on.

And for what its worth I am not disagreeing with your comments, just the bad attitude attached to some of them.

Posting up threads from a rival site is not allowed usually here, oh by the way= Post reported

 

[tazz]

Please do not post links to other advertised websites.

 

[baldsparkies]

Please do not post links to other advertised websites.

Sorry Tazz, genuine error.

The posts were relating to arguments regarding the use of 6mm cable on 8.5kw showers.

On paper its a no no. In practice on a 32a mcb they were finding no thermal damage or evidence of.
I would never condone this on a new install, far from it. But I have seen it myself and even 8.5kw on a 4mm with again no signs of thermal damage.
On the other hand I have come across a number of 45 amp pull switches with poorly connected cables often on the neutral side which have deffo signs of heat damage.
depends really on how long the showers in use and again installation criteria ect.
I am NOT saying its good practice or correct, just that it does happen, and can happen with no ill effects.
The opposite can also be true, with dire consequences, but thankfully I have never been witness to this.

Just a quick point,
Very often good qualified sparkies will get together in the real world.
They are different ages have been in the game for varying times.
Now as said I haven't actually met up with any who know of, or have subscribed to this sight.
But one thing I can say, face to face you can talk freely and discuss different viewpoints and opinions.
I am well known and respect them for who they are and what they know.
Never would they say or imply that a 61 year old man who has been in this industry since the age of 17.
Covered an apprenticeship C&G 236 part 1,2, B and C. 16th 17th 2391
JIB registered approved and Site manager gradings.
Worked and run commercial installs for Aldi ,Q-Fit, Frenchay Hospital cleft unit. Ushers pubs. Texaco garage installs along with the gilbarco lads, a great bunch as I remember. (Cold windy wet and making off MI's. No not fond memories there)
Anyway I digress, as !!!! incompetent.
But you come onto a forum such as this and well !! It speaks for itself.
I noted a comment about coming on the site to build up there post count, and to boast about what they do or do not know.
There is an underlying ego problem going on here, and of course this aint part of the real world.
I won't be posting up again, because I have become highly suspicious of the types of people that are on here.
By that I mean some of the regular posters who seem to be drawing together against new meat so to speak.
Its not healthy.
Sorry if I have rattled cages, but it needs to be said.

This link shouldn't draw moderation hopefully

http://www.electriciansforums.co.uk...ons/48104-using-8-5kw-shower-6mm-circuit.html

 

[Diddy]

I won't be posting up again, because I have become highly suspicious of the types of people that are on here.

Ignoring my own opinion on weather you were right or wrong what I would say is IF you believe in something -Enjoy giving out advice and have a bit of a moan as well as a giggle then imho you are shooting yourself and potentially others in the foot. If you think there is an undercurrent as well as some ego's on here you can always put your own point across and move on to the next post. For goodness sake don't let tinternet make you mad in real life.....it really isn't worth it !!

My take ? I wouldn't have given a plumber the advice...as we all know plumbers are.......lol - Add to the fact that being a DIY'r which he is to this trade then the chances of a loose connection or some other nonsense increases.....the other reason for me not giving the advice is pure selfish protectionism.....I want the bugger to call me for the job....just as I call him when I want to put a new bog/sink or whatever in...otherwise we both starve.
I always saw this place as a sparks discussion site with the odd bit of DIY advice chucked in....there is plenty for us sad buggers to chat about.

 

[D Skelton]

Sorry Tazz, genuine error.

The posts were relating to arguments regarding the use of 6mm cable on 8.5kw showers.

On paper its a no no. In practice on a 32a mcb they were finding no thermal damage or evidence of.
I would never condone this on a new install, far from it. But I have seen it myself and even 8.5kw on a 4mm with again no signs of thermal damage.
On the other hand I have come across a number of 45 amp pull switches with poorly connected cables often on the neutral side which have deffo signs of heat damage.
depends really on how long the showers in use and again installation criteria ect.
I am NOT saying its good practice or correct, just that it does happen, and can happen with no ill effects.
The opposite can also be true, with dire consequences, but thankfully I have never been witness to this.

Just a quick point,
Very often good qualified sparkies will get together in the real world.
They are different ages have been in the game for varying times.
Now as said I haven't actually met up with any who know of, or have subscribed to this sight.
But one thing I can say, face to face you can talk freely and discuss different viewpoints and opinions.
I am well known and respect them for who they are and what they know.
Never would they say or imply that a 61 year old man who has been in this industry since the age of 17.
Covered an apprenticeship C&G 236 part 1,2, B and C. 16th 17th 2391
JIB registered approved and Site manager gradings.
Worked and run commercial installs for Aldi ,Q-Fit, Frenchay Hospital cleft unit. Ushers pubs. Texaco garage installs along with the gilbarco lads, a great bunch as I remember. (Cold windy wet and making off MI's. No not fond memories there)
Anyway I digress, as !!!! incompetent.
But you come onto a forum such as this and well !! It speaks for itself.
I noted a comment about coming on the site to build up there post count, and to boast about what they do or do not know.
There is an underlying ego problem going on here, and of course this aint part of the real world.
I won't be posting up again, because I have become highly suspicious of the types of people that are on here.
By that I mean some of the regular posters who seem to be drawing together against new meat so to speak.
Its not healthy.
Sorry if I have rattled cages, but it needs to be said.

This link shouldn't draw moderation hopefully

http://www.electriciansforums.co.uk...ons/48104-using-8-5kw-shower-6mm-circuit.html

Oh grow up and stop with the self pity will you. No one on here is calling you incompetent, no one is arguing the ---- with you to satisfy some kind of ego and no one is forming some kind of secret society to 'stick it' to the new members. All we have done is point out the potential dangers of giving out advice to people who shouldn't really be given it.

The only cage being rattled here is your own. Jesus, if you're this susceptible to throwing your toys out of the pram over someone online disagreeing with you God knows what life on site must be like for you?!

 

[Leesparkykent]

Oh grow up and stop with the self pity will you. No one on here is calling you incompetent, no one is arguing the ---- with you to satisfy some kind of ego and no one is forming some kind of secret society to 'stick it' to the new members. All we have done is point out the potential dangers of giving out advice to people who shouldn't really be given it.

The only cage being rattled here is your own. Jesus, if you're this susceptible to throwing your toys out of the pram over someone online disagreeing with you God knows what life on site must be like for you?!

i pointed out that he'd given the OP a green light, and I haven't been on this forum long at all. He needs to stop wallowing, and just accept the fact his advice was inappropriate.

 

[sparksburnout]

Can I just ask then, what is the point of this forum? :
1. It would appear that no one other than the approved "inner circle" is allowed to provide advice regarding any aspect of electrical work
2 Any one that Does is derided and ridiculed unless it meets with the above mentioned clans various opinions on any given topic, this one being a prime example.
3. Any one that asks a question other than some fairly in depth problem is met with criticism and branded a Electrical Trainee.

it would seem to me as a fairly new member that this forum is in reality just a meeting place for a select number of members, some of whom are obviously very nice guys but unfortunately a possible majority who just seem to have an axe to grind and resent any other member who dares to make comment or does not meet with the required degree of excellence.

I can cope with all this, and find it quite amusing most of the time, but what is the point of it?? Is it a social meting place for the "elect", or is it to assist others? If it is for professional electricians who have no tolerance for anyone other than those with select knowledge and experience , should it not be limited to them and not open to lesser mortals? A few guys on here are helpful, witty and a pleasure to read, but there are quite a few others who seem to have a permanent problem with life.

 

[Sparkie30]

Sorry Tazz, genuine error.

The posts were relating to arguments regarding the use of 6mm cable on 8.5kw showers.

On paper its a no no. In practice on a 32a mcb they were finding no thermal damage or evidence of.
I would never condone this on a new install, far from it. But I have seen it myself and even 8.5kw on a 4mm with again no signs of thermal damage.
On the other hand I have come across a number of 45 amp pull switches with poorly connected cables often on the neutral side which have deffo signs of heat damage.
depends really on how long the showers in use and again installation criteria ect.
I am NOT saying its good practice or correct, just that it does happen, and can happen with no ill effects.
The opposite can also be true, with dire consequences, but thankfully I have never been witness to this.

Just a quick point,
Very often good qualified sparkies will get together in the real world.
They are different ages have been in the game for varying times.
Now as said I haven't actually met up with any who know of, or have subscribed to this sight.
But one thing I can say, face to face you can talk freely and discuss different viewpoints and opinions.
I am well known and respect them for who they are and what they know.
Never would they say or imply that a 61 year old man who has been in this industry since the age of 17.
Covered an apprenticeship C&G 236 part 1,2, B and C. 16th 17th 2391
JIB registered approved and Site manager gradings.
Worked and run commercial installs for Aldi ,Q-Fit, Frenchay Hospital cleft unit. Ushers pubs. Texaco garage installs along with the gilbarco lads, a great bunch as I remember. (Cold windy wet and making off MI's. No not fond memories there)
Anyway I digress, as !!!! incompetent.
But you come onto a forum such as this and well !! It speaks for itself.
I noted a comment about coming on the site to build up there post count, and to boast about what they do or do not know.
There is an underlying ego problem going on here, and of course this aint part of the real world.
I won't be posting up again, because I have become highly suspicious of the types of people that are on here.
By that I mean some of the regular posters who seem to be drawing together against new meat so to speak.
Its not healthy.
Sorry if I have rattled cages, but it needs to be said.

This link shouldn't draw moderation hopefully

http://www.electriciansforums.co.uk...ons/48104-using-8-5kw-shower-6mm-circuit.html

Mate dont let any of these gods gifted sparks who know everything and they want to dictate what others should say get under your skin.

 

[baldsparkies]

I have taken the rope from around my neck, climbed down off the chair, and decided in the end, that maybe you do love me.
Tell you what though, this internet is amazing, type how to install a shower into google.
Who needs an electrician !!
And that, sadly is no joke.
I really must get a life though, this forum stuff is taking me away from the real world and its addictive.
No wonder my business partner keeps asking about all the spam saying so and so has replied to a thread you've subscribed to.
Now that's a reason to give this a rest for a few days.

 

[Silly Sausage]

No wonder my business partner keeps asking about all the spam saying so and so has replied to a thread you've subscribed to.
Now that's a reason to give this a rest for a few days.

You can turn those email notifications off.
Then this forum affair is your own guilty secret!

 

[uksparks]

it would seem to me as a fairly new member that this forum is in reality just a meeting place for a select number of members, some of whom are obviously very nice guys but unfortunately a possible majority who just seem to have an axe to grind and resent any other member who dares to make comment or does not meet with the required degree of excellence.

I can cope with all this, and find it quite amusing most of the time, but what is the point of it?? Is it a social meting place for the "elect", or is it to assist others? If it is for professional electricians who have no tolerance for anyone other than those with select knowledge and experience , should it not be limited to them and not open to lesser mortals? A few guys on here are helpful, witty and a pleasure to read, but there are quite a few others who seem to have a permanent problem with life.

There is a mixture of people on here, and the majority are good people, the issue is, people come on here saying they are all that and really they know nothing and just start to ask the most basic questions and they are the ones wrecking the industry and do on. It just wears a bit thin, the same questions time and time again from people who are supposedly practising electricians.

Ill be honest, I hated it on here at first, and kept saying to the mrs that it's full of ----ers and I'm going to stop using the forum, but look at me now, I'm approaching 3000 posts and spend more tme on here than with the mrs and know who the regulars are and can honestly say I like it and am addicted to it, you get to know who is who and what people are like.

I say, if you can't beat them, join them and be a ----er too! Just kidding about you all being a bunch of knobs, I like you all really.

 

[uksparks]

You can turn those email notifications off.
Then this forum affair is your own guilty secret!

Guilty, I feel like I'm cheating on the mrs!

 

[baldsparkies]

:icon12:

Can I just ask then, what is the point of this forum? :
1. It would appear that no one other than the approved "inner circle" is allowed to provide advice regarding any aspect of electrical work
2 Any one that Does is derided and ridiculed unless it meets with the above mentioned clans various opinions on any given topic, this one being a prime example.
3. Any one that asks a question other than some fairly in depth problem is met with criticism and branded a Electrical Trainee.

it would seem to me as a fairly new member that this forum is in reality just a meeting place for a select number of members, some of whom are obviously very nice guys but unfortunately a possible majority who just seem to have an axe to grind and resent any other member who dares to make comment or does not meet with the required degree of excellence.

I can cope with all this, and find it quite amusing most of the time, but what is the point of it?? Is it a social meting place for the "elect", or is it to assist others? If it is for professional electricians who have no tolerance for anyone other than those with select knowledge and experience , should it not be limited to them and not open to lesser mortals? A few guys on here are helpful, witty and a pleasure to read, but there are quite a few others who seem to have a permanent problem with life.

Do be careful,
That's paramount to Blasphemy on here

 

[D Skelton]

Can I just ask then, what is the point of this forum? :
1. It would appear that no one other than the approved "inner circle" is allowed to provide advice regarding any aspect of electrical work
2 Any one that Does is derided and ridiculed unless it meets with the above mentioned clans various opinions on any given topic, this one being a prime example.
3. Any one that asks a question other than some fairly in depth problem is met with criticism and branded a Electrical Trainee.

it would seem to me as a fairly new member that this forum is in reality just a meeting place for a select number of members, some of whom are obviously very nice guys but unfortunately a possible majority who just seem to have an axe to grind and resent any other member who dares to make comment or does not meet with the required degree of excellence.

I can cope with all this, and find it quite amusing most of the time, but what is the point of it?? Is it a social meting place for the "elect", or is it to assist others? If it is for professional electricians who have no tolerance for anyone other than those with select knowledge and experience , should it not be limited to them and not open to lesser mortals? A few guys on here are helpful, witty and a pleasure to read, but there are quite a few others who seem to have a permanent problem with life.

Right then, put your money where your mouth is.

Name the members of this so called 'inner circle'.

If you could, can you also tell us to what extent each of these members resents anyone else's right to comment?

I'd love to know, no really I would, because if there is an inner circle I'm sure as hell not a member! As I have such an overwhelming 'need' to feel like I belong, I just need to know where to sent my application form for inner circle membership.

 

[shanky887614]

Can I just ask then, what is the point of this forum? :
1. It would appear that no one other than the approved "inner circle" is allowed to provide advice regarding any aspect of electrical work
2 Any one that Does is derided and ridiculed unless it meets with the above mentioned clans various opinions on any given topic, this one being a prime example.
3. Any one that asks a question other than some fairly in depth problem is met with criticism and branded a Electrical Trainee.

it would seem to me as a fairly new member that this forum is in reality just a meeting place for a select number of members, some of whom are obviously very nice guys but unfortunately a possible majority who just seem to have an axe to grind and resent any other member who dares to make comment or does not meet with the required degree of excellence.

I can cope with all this, and find it quite amusing most of the time, but what is the point of it?? Is it a social meting place for the "elect", or is it to assist others? If it is for professional electricians who have no tolerance for anyone other than those with select knowledge and experience , should it not be limited to them and not open to lesser mortals? A few guys on here are helpful, witty and a pleasure to read, but there are quite a few others who seem to have a permanent problem with life.

in this case what the op was asking is ohm's law, the basic's of the basics.


V=IR
I=V/R
R=V/I

bassically to start with a 10kw shower would be 10,000 / 230 = 43Amps

so now you have your design current for your cable calc.

the cable you need for a 10kw shower depends on installation methods (clipped direct)

if it has loads of insulation along the route and other factors you might need a 16+mm cable (this is why we calculate cables in the first place)


and to answer your question, the members here get that bored and wound up from giving people the same advice everyday on how to wire a shed they get ratty

 

[tazz]

Baldsparkies & sparksburnout, Just like a building site, the forum is built up of experienced electricians from all sections of the industry. And being a member you need to understand constructive debate. The idea is to put your question in a tread, for others to to help and obvious prove their advice against proven BS regs and not against joe bloggs web info. As an experience tradesman, you should be able to debate with you own knowledge of the BS, again in a constructive manner. Members such as yourself are free to express their views, aslong as they are not abusive, racist or classed as bullying. May I suggest a new constructive way forward, to answer your questions

 

[HandySparks]

in this case what the op was asking is ohm's law, the basic's of the basics.


V=R/I
I=R/V
R=IxV

bassically to start with a 10kw shower would be 10,000 / 230 = 43Amps

....

Really?

 

[Knobhead]

After slogging through this thread all I can say is:

I’m BORED!

 

[baldsparkies]

Using 6mm to supply an 8.5kw shower is WRONG.
Unless your a qualified electrician you should NOT be doing the job because of the many variables, and safety is paramount.
But real world scenario is often very different, and in your working life you will often come across situations that conflict with calculations, and regs.
When that happens you need to ask, how so !!
As an example there are situations where an 8.5 kw shower will be fed from a 6mm cable on a 32 amp mcb over many years and show no signs of thermal damage, or have given any problems to the user.
Calculations and regs will say otherwise, real life is often very different.
Of course your maxing these situations out, which is far from a good idea.
next time your running an 8.5kw shower.
Check your 230v supply and see what your really getting. Clamp test the shower and see what its really pulling.
Then maybe you will see why sometimes 6mm will appear to suffice despite all the theory.
ITS still WRONG and I don't dispute that but it is possible.
My comments are for qualified electricians, not for Joe public.
So Joe public take note. The fall out I am receiving is to protect YOU not me.

 

[Guest77]

Changed my mind, I don't want him to get his skirt ripped.

 

[Andy78]

Using 6mm to supply an 8.5kw shower is WRONG.

I'd best not use my shower until I've got my metal CU fitted then.

 

[andyelectric]

Been reading this thread with interest. Whilst I do not agree that there is an 'inner circle' on here I do feel that there some pretty much 'hardcore' views that have been agreed on by a large group. A large number (but not all) of this large group are on other sites where they seem freer to 'co-ordinate' viewpoints about certain things.

Here's the 3 points I think that have been agreed.

1. If a person is asking a question and is not a 'qualified electrician' only the answer get a qualified electrician in is appropriate.
2. To be a 'qualified electrician' only a time served apprenticeship is appropriate. Electrical Trainee do not count.
3. Due to the fact that the government through Competent Person Scheme seems to be recognising Electrical Trainee reform of the industry is required. A proper register limiting electrical work to those in (2.) is required.

All these 3 statement are applied under the guise of public safety. And I do not dispute that application of these statements would improve safety. (How much is subjective).

It is my feeling though that the main thrust is to 'preserve the bottom line'.

1. Try and prevent diy if it could mean a sparkie getting the work.
2/3. Try and keep this work to 'proper sparkies' that have completed the same training as us, cause that'll push prices back up.

Let me qualify by saying that I know there will be many that fall on the safety as opposed to profit side of my above statement, so please don't just try to shout me down as it is pretty obvious no one is going to admit being on the other 'purely profit motivated' side of the fence.

 

[Anthony S]

Been reading this thread with interest. Whilst I do not agree that there is an 'inner circle' on here I do feel that there some pretty much 'hardcore' views that have been agreed on by a large group. A large number (but not all) of this large group are on other sites where they seem freer to 'co-ordinate' viewpoints about certain things.

Its not hard core views, it the case that there's a few members/posters who know their stuff and they try to advise others, but it comes across as though they are digging people out when they are not and people take it to heart.

 

[Guest77]

I'd best not use my shower until I've got my metal CU fitted then.

Very true, and the 8.5 kw shower which is working at my parents house wired in a 6mm2 cable which is at least 12 years old now must be switched off immediately as well.

 

[telectrix]

Very true, and the 8.5 kw shower which is working at my parents house wired in a 6mm2 cable which is at least 12 years old now must be switched off immediately as well.

so, wtf do you know about showers?

http://www.electriciansforums.co.uk/chit-chat-off-topic/98832-help-please-3.html

:smilielol5::smilielol5::smilielol5::smilielol5::smilielol5:

 

[Andy78]

Been reading this thread with interest. Whilst I do not agree that there is an 'inner circle' on here I do feel that there some pretty much 'hardcore' views that have been agreed on by a large group. A large number (but not all) of this large group are on other sites where they seem freer to 'co-ordinate' viewpoints about certain things.

Here's the 3 points I think that have been agreed.

1. If a person is asking a question and is not a 'qualified electrician' only the answer get a qualified electrician in is appropriate.
2. To be a 'qualified electrician' only a time served apprenticeship is appropriate. Electrical Trainee do not count.
3. Due to the fact that the government through Competent Person Scheme seems to be recognising Electrical Trainee reform of the industry is required. A proper register limiting electrical work to those in (2.) is required.

All these 3 statement are applied under the guise of public safety. And I do not dispute that application of these statements would improve safety. (How much is subjective).

It is my feeling though that the main thrust is to 'preserve the bottom line'.

1. Try and prevent diy if it could mean a sparkie getting the work.
2/3. Try and keep this work to 'proper sparkies' that have completed the same training as us, cause that'll push prices back up.

Let me qualify by saying that I know there will be many that fall on the safety as opposed to profit side of my above statement, so please don't just try to shout me down as it is pretty obvious no one is going to admit being on the other 'purely profit motivated' side of the fence.

You can file me under both your categories. However when dishing advice on the internet it's the safety aspect that is the overruling one for me, as anonymity is a veil that prevents me from easily assessing someone I have never met.
When it comes to basic questions such as this one, anyone who should know, should know and anyone who doesn't know shouldn't be doing it and should not be advised how to.
There are certain tasks that I feel DIYers should be able to carry out in their own home. Unfortunately I also don't advise on that on this forum due to the anonymity issue again, and the way the DIY forum is set up on here.
My reluctance to give information due to safety is purely a "getting to sleep at night" thing and not to do with legal implications.
Week after week members on here give advice to new members with 1 post count both in the main and DIY forum, which is totally irresponsible in my book.

 

[pennychew]

Very true, and the 8.5 kw shower which is working at my parents house wired in a 6mm2 cable which is at least 12 years old now must be switched off immediately as well.

Not when one of thems using it though, that would be mean

 

[shanky887614]

Using 6mm to supply an 8.5kw shower is WRONG.
Unless your a qualified electrician you should NOT be doing the job because of the many variables, and safety is paramount.
But real world scenario is often very different, and in your working life you will often come across situations that conflict with calculations, and regs.
When that happens you need to ask, how so !!
As an example there are situations where an 8.5 kw shower will be fed from a 6mm cable on a 32 amp mcb over many years and show no signs of thermal damage, or have given any problems to the user.
Calculations and regs will say otherwise, real life is often very different.
Of course your maxing these situations out, which is far from a good idea.
next time your running an 8.5kw shower.
Check your 230v supply and see what your really getting. Clamp test the shower and see what its really pulling.
Then maybe you will see why sometimes 6mm will appear to suffice despite all the theory.
ITS still WRONG and I don't dispute that but it is possible.
My comments are for qualified electricians, not for Joe public.
So Joe public take note. The fall out I am receiving is to protect YOU not me.

your a fool if you believe that, your cable calcs will prove otherwise, an 8.5kw shower is a 37amp load so 40a mcb will do which means 6mm is fine not allowing for any derating factors

 

[baldsparkies]

your a fool if you believe that, your cable calcs will prove otherwise, an 8.5kw shower is a 37amp load so 40a mcb will do which means 6mm is fine not allowing for any derating factors

Here we go again.
Why conclude that someone is a fool without thinking your statement through.
How can you possibly say that 6mm is fine, and then follow up by saying (by not allowing any de rating factor)
That's the entire point of being a qualified electrician.
You WILL include de rating factors into your calculations, joe public will not.
What I am saying is that its wrong to make a blanket decision regarding 6mm.
Hence my comment (Broadly speaking, up to 8.5kw 6mm beyond that 10mm) but and its a big but other variables have and should always be taken into account.
If your unsure what those variables are or how to apply them then consult a qualified electrician.
I sometimes feel that often comments are miss-read, miss-understood, or even miss-phrased by the poster.
But I find it a bit sad and disappointing when there are people that you respect, waiting to pounce on your every word with the sole intention of calling you a fool, blind, or even incompetent.
Nothing I have said is either wrong, or inaccurate.
Sometimes you just need to think outside the box, and give the other guy a bit of breathing space.
As qualified electricians we should all be able to do this without throwing around insults based on our individual points of view or opinions.
As said real world it simply doesn't work that way.
That's why on the forum you will call a 6' 6" bloke all muscle and weighing 18 stone a dick head.
And in the real world, keep it to yourself and call him a dick head under your breath lol xx

 

[Guest125]

in this case what the op was asking is ohm's law, the basic's of the basics.


V=R/I
I=R/V
R=IxV

bassically to start with a 10kw shower would be 10,000 / 230 = 43Amps

so now you have your design current for your cable calc.

the cable you need for a 10kw shower depends on installation methods (clipped direct)

if it has loads of insulation along the route and other factors you might need a 16+mm cable (this is why we calculate cables in the first place)


and to answer your question, the members here get that bored and wound up from giving people the same advice everyday on how to wire a shed they get ratty

If I do not want to give advice then I just don't. Surely this would be a better way to approach a thread that someone feels is not worth their time rather that slagging off other posters?

 

[Guest125]

Using 6mm to supply an 8.5kw shower is WRONG.
Unless your a qualified electrician you should NOT be doing the job because of the many variables, and safety is paramount.
But real world scenario is often very different, and in your working life you will often come across situations that conflict with calculations, and regs.
When that happens you need to ask, how so !!
As an example there are situations where an 8.5 kw shower will be fed from a 6mm cable on a 32 amp mcb over many years and show no signs of thermal damage, or have given any problems to the user.
Calculations and regs will say otherwise, real life is often very different.
Of course your maxing these situations out, which is far from a good idea.
next time your running an 8.5kw shower.
Check your 230v supply and see what your really getting. Clamp test the shower and see what its really pulling.
Then maybe you will see why sometimes 6mm will appear to suffice despite all the theory.
ITS still WRONG and I don't dispute that but it is possible.
My comments are for qualified electricians, not for Joe public.
So Joe public take note. The fall out I am receiving is to protect YOU not me.

We are putting in new shower supplies in at Clapham.

8.5kW = 37A
40A OCPD required
single cable in surface trunking has a max of 41A for 6mm cable.

6mm cable it is then...

 

[Octopus]

We are putting in new shower supplies in at Clapham.

5.8kW = 37A
40A OCPD required
single cable in surface trunking has a max of 41A for 6mm cable.

6mm cable it is then...

So you are back and immediately you are being a dxck.

Please don't hand out detailed advice on the public forum

Thanks

 

[Guest125]

Here we go again.
Why conclude that someone is a fool without thinking your statement through.
How can you possibly say that 6mm is fine, and then follow up by saying (by not allowing any de rating factor)
That's the entire point of being a qualified electrician.
You WILL include de rating factors into your calculations, joe public will not.
What I am saying is that its wrong to make a blanket decision regarding 6mm.
Hence my comment (Broadly speaking, up to 8.5kw 6mm beyond that 10mm) but and its a big but other variables have and should always be taken into account.
If your unsure what those variables are or how to apply them then consult a qualified electrician.
I sometimes feel that often comments are miss-read, miss-understood, or even miss-phrased by the poster.
But I find it a bit sad and disappointing when there are people that you respect, waiting to pounce on your every word with the sole intention of calling you a fool, blind, or even incompetent.
Nothing I have said is either wrong, or inaccurate.
Sometimes you just need to think outside the box, and give the other guy a bit of breathing space.
As qualified electricians we should all be able to do this without throwing around insults based on our individual points of view or opinions.
As said real world it simply doesn't work that way.
That's why on the forum you will call a 6' 6" bloke all muscle and weighing 18 stone a dick head.
And in the real world, keep it to yourself and call him a dick head under your breath lol xx

There does appear to be a few on here that know full well that a post is meant generally and they enjoy to show how big their BS7671 testicles are and pick holes rather than just give their version of a solution.

 

[Guest125]

So you are back and immediately you are being a dxck.

Please don't hand out detailed advice on the public forum

Thanks

Please do not call me that.

It was NOT advice for the Op but a direct REPLY to the quote saying that a 6mm cable could not be used. The reply was quoted so I though that would be obvious. On top of that I wrote WE. As in WE are doing this. WE are qualified electricians. and WE are doing the work.

 

[shanky887614]

Please do not call me that.

It was NOT advice for the Op but a direct REPLY to the quote saying that a 6mm cable could not be used. The reply was quoted so I though that would be obvious. On top of that I wrote WE. As in WE are doing this. WE are qualified electricians. and WE are doing the work.

i think you have a typo mate.

i think you mean 8.5

 

[Guest125]

i think you have a typo mate.

you put 5.8kw i think you mean 8.5

Yeah sorry. I will now climb off my high horse.

 

[telectrix]

We are putting in new shower supplies in at Clapham.

5.8kW = 37A
40A OCPD required
single cable in surface trunking has a max of 41A for 6mm cable.

6mm cable it is then...

well at least get ohm's law right. 5800/230 = 25.22 A according to my arithmetic.

 

[shanky887614]

well at least get ohm's law right. 5800/230 = 25.22 A according to my arithmetic.

ah but it wouldnt be a 5.8 would it.

i have only come across 6,8.5 or 10kw electric shows

the manufacturer's like round nunbers

 

[Guest125]

ah but it wouldnt be a 5.8 would it.

i have only come across 6,8.5 or 10kw electric shows

the manufacturer's like round nunbers

Talking od typos........LOL

 

[baldsparkies]

well at least get ohm's law right. 5800/230 = 25.22 A according to my arithmetic.

Yer right Tel.
But why 230v ?? is this by enquiry, assumption, or a true measured rms voltage.
Thinking outside the box (not recommended for DIY man, go away)
but food for thought never the less.
Be gentle with me no more abuse pleeeeese, lol.

 

[shanky887614]

Yer right Tel.
But why 230v ?? is this by enquiry, assumption, or a true measured rms voltage.
Thinking outside the box (not recommended for DIY man, go away)
but food for thought never the less.
Be gentle with me no more abuse pleeeeese, lol.

if its 250 then it would be less.

its rare to see 220v and even then it would only increase a little

 

[Andy78]

Yer right Tel.
But why 230v ?? is this by enquiry, assumption, or a true measured rms voltage.
Thinking outside the box (not recommended for DIY man, go away)
but food for thought never the less.
Be gentle with me no more abuse pleeeeese, lol.

It is standard practice to use the nominal Uo value for all calculations.

 

[Silly Sausage]

if its 250 then it would be less.

its rare to see 220v and even then it would only increase a little

No no no!
The current will increase with voltage.
The power rating is quoted at a certain voltage.

 

[telectrix]

beat me to it. using 230V will give a worse ( higher) value for current than using the actual ( 235 -240V ) so errs on the side of caution.

 

[baldsparkies]

Its even more rare to see 230v shanks, and often that's the baseline that's used for obvious reasons.
And yet when I dared to suggest 6mm as a possible cable size for 8.5kw I was summary abused ??
Despite that, it will be used. And if Mr DIY is going to use it it's wrong.
But on an electricians forum, and with all other factors taken into account,can and does prove satisfactory in the real world.
So there you have it, some people are getting trashed for saying 6mm, some people quite happy to use 6mm.
Hope others are paying attention here, cus amongst qualified electricians there are indeed differences of opinion, and you know what dependant on the situation both are entirely correct.
And that's the whole point, and no abuse needed.

 

[GEOFF S]

Well if Baldsparkies wasn't bald, he will be now! Crikey, a vague question got a vague answer, like most questions and answers on the forums! All this bickering over such trivia lol. Come on chaps