Maximum cable length.........??

[mickytuff]

Good afternoon all, firstly im pretty rubbish at cable calcs. My question is this, the load on the circuit is 6.6kw for a outdoor ev charger so the cable would be clipped direct. Using 4mm NYY cable is ok subject to the cable length, any ideas on the maximum cable length before having to use 6mm. All suggestions/advice greatly received :drunk:

 

[Darkwood]

Show us your cable calcs first and we will guide you if we see any errors we are not a free calculation service ... we need to see have have a grasp of the regulations.

 

[mickytuff]

The last time I needed to do cable calcs was in 1998 to pass my exams..... it was a question, I wasn't looking for an interigation.........

 

[snowhead]

The last time I needed to do cable calcs was in 1998 to pass my exams..... it was a question, I wasn't looking for an interigation.........

Nobody expects an interigation..

Or should that be the Spanish Inquisition..

Both amount ot the same thing on here tho'

Simple calculator for electric cable size.

 

[GMES]

Micky I think what Darkwood means is if you are undertaking electrical work then you should know the basics.
It is not aimed at you in a negative way, it's just that of late there as been a wave of chancers on the forums asking basic ,classroom questions. And as he said the forum is not here just to give answers to people who can't be bothered to do their own homework, also mate to say you have not calculated cable since your exams is quite a worrying statement.

 

[mickytuff]

Its not a worrying statement at all. Nearly all circuits installed are the standard types, ie ringfinals on 32A, lighting on 6A, cookers on 32A if 6mm and 40A/45A if 10mm, it was a simple question which I hoped would be easily explained to me rather than now feeling hacked off and getting my on site quide out and working it out myself. which I will now do using the relevant formula on page 139 and subsequent pages to get the correct answer. I thought a forum was for discussions and to help others. Very disappointed.......

 

[Tridentsystems]

Ahh bless

 

[ian.settle1]

Its not a worrying statement at all. Nearly all circuits installed are the standard types, ie ringfinals on 32A, lighting on 6A, cookers on 32A if 6mm and 40A/45A if 10mm, it was a simple question which I hoped would be easily explained to me rather than now feeling hacked off and getting my on site quide out and working it out myself. which I will now do using the relevant formula on page 139 and subsequent pages to get the correct answer. I thought a forum was for discussions and to help others. Very disappointed.......

Oh yes it is, as how are you complying with the regs when it comes to carrying out a correct electrical design or are you one of the people who says it's 1.5 for this and 2.5 for that as that was how I was taught and it is always right?

 

[telectrix]

Its not a worrying statement at all. Nearly all circuits installed are the standard types, ie ringfinals on 32A, lighting on 6A, cookers on 32A if 6mm and 40A/45A if 10mm, it was a simple question which I hoped would be easily explained to me rather than now feeling hacked off and getting my on site quide out and working it out myself. which I will now do using the relevant formula on page 139 and subsequent pages to get the correct answer. I thought a forum was for discussions and to help others. Very disappointed.......

then whynot use the simple calculator snowhead has very kindly posted a link to. if that's too much trouble, maybe you should consider plumbing as a trade.

 

[Sparky Ninja]

The last time I needed to do cable calcs was in 1998 to pass my exams..... it was a question, I wasn't looking for an interigation.........

I too am intrigued as to how they have been done since? Or has it taken this long to get your first job?

 

[telectrix]

Oh yes it is, as how are you complying with the regs when it comes to carrying out a correct electrical design or are you one of the people who says it's 1.5 for this and 2.5 for that as that was how I was taught and it is always right?

sadly, in the domestic sector, it's frequently done that way. 9 times out of 10, the installer gets away with it by luck.

 

[mickytuff]

Very true, thankyou Snowhead for your link, very handy tool. And I think this thread is going very ---- now, to suggest that most circuits installed aren't common cable sizes/breaker sizes is ridiculous.Take that how you want to.

 

[Darkwood]

Its not a worrying statement at all. Nearly all circuits installed are the standard types, ie ringfinals on 32A, lighting on 6A, cookers on 32A if 6mm and 40A/45A if 10mm, it was a simple question which I hoped would be easily explained to me rather than now feeling hacked off and getting my on site quide out and working it out myself. which I will now do using the relevant formula on page 139 and subsequent pages to get the correct answer. I thought a forum was for discussions and to help others. Very disappointed.......

We are always happy to help but with all respect we expect the initial poster to show a basic understanding to show us that we are not doing all the ground work for their DIY project etc ... as i said we help each other but we are not a free calculation service nor do we do homework so don't take it the wrong way - your profile has no info of qualifications or even if your an Electrician hence i asked you to show you have an understanding... we all can quote page no's but understanding the content and utilising it is a different matter..

I don't understand what the issue is here you make it sound like a tedious long winded task where its a simple 5min calc about the same time it took you to actually log in and ask the question.

PS -Agree its very worrying that you claim to not have bothered with cables calcs since 1998 it seems the college failed to explain how crucial there use is and why rule of thumb shouldn't be used... your claim that nearly all circuits are standard type etc well as mcb rating goes maybe but this won't account for zs compliance before you wire circuit and not finding out after its too high, volts drop etc how can you possible know before hand without calculation.... sorry but with the influx of insulating existing builds and new builds been Energy efficient its now more crucial than at any other time to ensure you use cable calcs to ensure compliance.... ive just done a ring in 4mm because of insulated stud walls...your rule of thumb could see a 2.5mm overheat so il reiterate ... show us your take on the calculations if you still remember after 15yrs.

 

[Octopus]

Judging by some of you previous posts you need to brush up on the regs, calcs and if you haven't got the BGB you need one.

 

[Darkwood]

We give our advice on a professional level you either take it leave it.

We don't do anyone's homework
We don't do all the hard work for anyone who cannot be bothered
We don't provide a free calculation service for any tom dick or harry to abuse our help

So to show we are not been used we simply ask you also help yourselves a little and show us your take on what you ask, to be told we are ---- for ensuring the forum doesn't end up been a homework answer service and DIY free calcs etc is pretty low .... TBH admitting you haven't bothered doing a cable calc since 1998 really says it all and explains fully why you asked the question in the first place.