Spur off immersion ?

c.a.r.l

Actually enmac, you can spur from a radial one double or one single. I am simply explaining to someone that this practice is not dangerous. Are you telling me that you have never carried out a safe procedure when in a precarious situation?!

In relation to the 30a Junction box..you have completely taken this out of context! If you read the posts more carefully and stop jumping to write stupit ignorant replies you will see that. If you dont have something educational or less ignorant to add please mind your own business.

How dare you!!

enmac

c.a.r.l wrote: »

Actually enmac, you can spur from a radial one double or one single. I am simply explaining to someone that this practice is not dangerous. Are you telling me that you have never carried out a safe procedure when in a precarious situation?!

In relation to the 30a Junction box..you have completely taken this out of context! If you read the posts more carefully and stop jumping to write stupit ignorant replies you will see that. If you dont have something educational or less ignorant to add please mind your own business.

How dare you!!

Yes Carl , you can spur from a radial socket circuit - we're talking about the immersion circuit here and it's not permissible to spur a socket off this to feed a TV - If i'm wrong please point out the error

You're reply to the junction box issue has not provided any further information

You quoted my contribution in your original post - I am perfectly entitled to a reply - In any case the OP has taken my advice and got a competent sparks to resolve the issue without contravening the wiring rules

'safe procedure in a precarious situation' - if you eliminate the precarious situation then you won't need a safe procedure - that's what happened inthe end

Hope you learnt a lesson

Bruthal

A list of the dangers of spuring off the immersion would be interesting, i would`t do it myself, but i dont see the dangers involved either.
A 5 amp socket definitely would`t be great for sure, as no fuse in the plug itself, but a 13 amp socket off it, wheres the danger in that. The immersion circuit is just like a socket circuit with a 3kw kettle connected,
so a socket with a tv plugged in does`t seem a big deal, why put a fused spur, if someone plugged in a 2kw heater while the immersion is on where`s the danger,

Regulations might say no, i dont know that for certain myself, regulations are there as a general safetly measure and change from time to time, and they dont always get tighter, sometimes they relax a little,

Its better practice to leave immersion to its own circuit alone, but hardly dangerous to connect a socket to it,

And what about branching off a ring main to a socket in the attic? is that ok, or against regulations, and if you were adding in a socket to the attic, would you wire back to the board in a house with a ring main, Ring mains themselves should be against regs i think

Bruthal

fishdog wrote: »

No for as long as I can remember though. Perhaps I am older than you :D There was a time when they were not on the RCD because it was thought they may cause nuisense tripping. Any house wired in the last 20 years should have its immersion on the RCD, but there are still some houses out there with 40 year old wiring :eek::eek:



I remember the time no RCD`s were on immersion too, and showers as well.
The nuisence tripping was indeed a concern, but the RCD is one brilliant device, i dont think anyone who has an understanding of them would feel comfortable even using a shower that does`t have one controlling it.

2011

but a 13 amp socket off it, wheres the danger in that.

Here qre 2 I can think of, I am sure there are more:
1) If someone turns off every MCB in the board that is marked "socket" this one would still be live.

2) It is bad practice to ignore the wiring regulations. It can stsrt with a minor infringement and snowball from there.

The immersion circuit is just like a socket circuit with a 3kw kettle connected

Except that a kettle can not remain switched on for hours on end.

why put a fused spur

This is normal for fixed equipment and it stops someone doing something likeplugging in

a 2kw heater while the immersion is on

where`s the danger

There may be none, but MCBs can fail. It is always better to try to design a circuit so that it is not overloaded.

Regulations might say no, i dont know that for certain myself

A TV fed from the immersion is banned I can assure you.

Its better practice to leave immersion to its own circuit alone

I agree

And what about branching off a ring main to a socket in the attic? is that ok, or against regulations

It is permitted at present, once the entire circuit covers no more than 100m^2

Ring mains themselves should be against regs i think

They will be for socket circuits from September next.

Merch

robbie7730 wrote: »

Regulations might say no, i dont know that for certain myself, regulations are there as a general safetly measure and change from time to time, and they dont always get tighter, sometimes they relax a little,

Its better practice to leave immersion to its own circuit alone, but hardly dangerous to connect a socket to it,

And what about branching off a ring main to a socket in the attic? is that ok, or against regulations, and if you were adding in a socket to the attic, would you wire back to the board in a house with a ring main, Ring mains themselves should be against regs i think

Sorry can you explain this, why would a ring main be against regulations?
Perhaps I have misread this? but a 2.5mm^2 spur is = to 2.5mm^2 but in a ring circuit it is equal to 5.0mm^2

Bruthal

2011 wrote: »

Here qre 2 I can think of, I am sure there are more:
1) If someone turns off every MCB in the board that is marked "socket" this one would still be live.

relabel

2) It is bad practice to ignore the wiring regulations. It can stsrt with a minor infringement and snowball from there.

Spur from ring main is within regs, is it right?? ie 2.5 backed by 32amp mcb


Except that a kettle can not remain switched on for hours on end.

and the danger of immersion on for hours is???


This is normal for fixed equipment and it stops someone doing something likeplugging in

The danger of plugging something in is???


There may be none, but MCBs can fail. It is always better to try to design a circuit so that it is not overloaded.


A TV fed from the immersion is banned I can assure you.




I agree


It is permitted at present, once the entire circuit covers no more than 100m^2


They will be for socket circuits from September next.

Well i did not say it should be done, just where are the dangers, i agree with not doing it, but cant i ask what peoples opinions on the dangers are

Immersion mcb can be relabeled, would you work on a socket according to switching off by its label

immersion left on hours on end,,,, wheres the danger?

The regulations? I agree, keep within regs for sure
But its within regs to branch off to a single socket from a ring main you say, so you have a 2.5 cable backed by a 32amp mcb, hardly great, and surely worse than connecting a socket to a 20amp protected circuit

And using spur, no problem using that but whats problem using socket, what danger is there from someone plugging in, spurs are used for fixed appliances as you said, but with an RCD on immersion then a socket would be hardly a danger.

Tv fed from immersion, well its not connected to the immersion element.

Anyway, its just a matter of interest question, not a recommendation to use immersion circuit as a socket circuit, so keep that in mind

Bruthal

Merch wrote: »

Sorry can you explain this, why would a ring main be against regulations?
Perhaps I have misread this? but a 2.5mm^2 spur is = to 2.5mm^2 but in a ring circuit it is equal to 5.0mm^2

Well my thought on ring mains is why use them, you have a 32 amp mcb with 13 amp sockets, also if a loose connection occurs in a socket, it will not show up, unless it happens in 2 places, but now you have in effect 2 radials of 2.5 wiring but still backed by a 32amp breaker. Radials do the job grand i would of thought, and they show up any faults which ring mains may not,

Also if you spur off it the spur circuit now has 2.5 cable backed by 32 amp protection,

Again im just wondering what others think

2011

Immersion mcb can be relabeled

True

would you work on a socket according to switching off by its label

No, but the point is some people would.

immersion left on hours on end,,,, wheres the danger?

I was highlighting the difference between athe kettle and the immersion.

Sorry Robbie I will reply to the rest of your post later, I have to run!

stevoslice

RoundyMooney wrote: »

I put everything through an RCD these days, what with the forthcoming changes in the regs.

What are these changes you speak of?

Bruthal

c.a.r.l wrote: »

Hi,
As an Electrical Teacher I would calculate the following:

The immersion is fed using what we call a radial circuit, This circuit is made up of a 20amp MCB and Rcd, a 2.5mm sq cable.

You can "spur" off this providing a fused spur is used..let me explain, from the immersion switch/spur a cable is tapped of this and in to feed a "fused connection unit". it is from this fused connection unit that the socket for your lcd is supplied. This is a very simple,straightforward and safe procedure.
There is no problem in doing this provided the above is adhered to.

Let me do the maths for you... An immersion heater can use up to 3kw (3000 Watts), I would assume the lcd would not take more than 400watts, so lets say 1000 watts for the lcd (this will never be the case unless its the size of a cinema screen!)

So using ohms law I (Current) = P (Power) Devided by V (Voltage).....
so..I = 4000/230 = 17.3 AMPS

A 2.5mmsq cable is capable of carring 28 amps approx. Realisticly you are not even using half the potential of the cable.

I hope this helps, but if you need any further advice please email me your number and I will give you a buzz.

Carl

I think any electrician on this forum can calculate that, and while i have said i dont really see any dangers of spuring off the immersion, its best and proper practice not to, it keeps the electrical installation clean and simple.

For instance it would`t really be any more dangerous to spur from the shower isolator or pull chord using a fused spur close to the shower isolator than it would from immersion circuit. But i would`t like to think anyone would do that.

As your calculations show, the immersion circuit would`t be overloaded during normal use, and is electrically sound. Its just proper practice to keep the immersion for its own use on the circuit, or as others said maybe
power water valves or a pump within the hot press from it.

2011

But its within regs to branch off to a single socket from a ring main you say, so you have a 2.5 cable backed by a 32amp mcb, hardly great, and surely worse than connecting a socket to a 20amp protected circuit

You make a fair point here. I do agree with you that it does not nake much sense to spur off a ring circuit, but my point is that according to current regulations you are permitted to do this.

Well my thought on ring mains is why use them, you have a 32 amp mcb with 13 amp sockets, also if a loose connection occurs in a socket, it will not show up, unless it happens in 2 places, but now you have in effect 2 radials of 2.5 wiring but still backed by a 32amp breaker. Radials do the job grand i would of thought, and they show up any faults which ring mains may not,

Also if you spur off it the spur circuit now has 2.5 cable backed by 32 amp protection,

Again im just wondering what others think

I agree with you here completly.
In addition:
Accroding to the regulations you can have an unlimited nu,ber of sockets fed from a ring circuit once it is within 100m^2. Therfore in theory a single circuit could have 1000 sockets on it!!! That is crazy.

Bruthal

2011 wrote: »

You make a fair point here. I do agree with you that it does not nake much sense to spur off a ring circuit, but my point is that according to current regulations you are permitted to do this.



I agree with you here completly.
In addition:
Accroding to the regulations you can have an unlimited nu,ber of sockets fed from a ring circuit once it is within 100m^2. Therfore in theory a single circuit could have 1000 sockets on it!!! That is crazy.

yes ive said for a long time ring mains are not good, i never liked them since apprentice days,
My whole point about regs is they are not perfect, but its good practice to keep within them, no competent person will argue with that,

But when anyone says something is wrong because its outside the regs, or something is correct because the regs say it is, is it absolutely gospel?

2011

But when anyone says something is wrong because its outside the regs, or something is correct because the regs say it is, is it absolutely gospel?

IMHO when an installation is certified the cert itself is a legal document. If you ignore/break the regulations and sign off on it you could be in hot water.

I do agree that it is possible to do a job that complies with the regulations but is still done to a poor standard. The ring socket circuit is an example of that.

Bruthal

2011 wrote: »

IMHO when an installation is certified the cert itself is a legal document. If you ignore/break the regulations and sign off on it you could be in hot water.

I do agree that it is possible to do a job that complies with the regulations but is still done to a poor standard. The ring socket circuit is an example of that.

yes agreed

davelerave

robbie7730 wrote: »

Well my thought on ring mains is why use them, you have a 32 amp mcb with 13 amp sockets, also if a loose connection occurs in a socket, it will not show up, unless it happens in 2 places, but now you have in effect 2 radials of 2.5 wiring but still backed by a 32amp breaker. Radials do the job grand i would of thought, and they show up any faults which ring mains may not,

Also if you spur off it the spur circuit now has 2.5 cable backed by 32 amp protection,

Again im just wondering what others think

advantages for rings:increased csa/capacity.reduced voltage drop for longer runs.i would do spurs normally in 3*4 so not an issue really.
other misc. advantages :ring can be split in case of damage or fault,also earth continuity is mainatained in a single break
the major issue obviously is an undetected break in L or N reducing the capacity of the circuit

2011

Personally I think the disadvantages outweigh the advantages. Either way they will be banned soon.

also earth continuity is mainatained in a single break

.....but the earth fault loop impedence may then be too high for a 32A MCB.

davelerave

true

PaulieBoy

If you where to spur of the Immersion to feed an outlet and then got a RECCI guy out to cert the house, would he pass it ???

2011

If you where to spur of the Immersion to feed an outlet and then got a RECCI guy out to cert the house, would he pass it ???

If the spur was used to feed something located in the hot press like a shower pump then you would be ok. For a TV, no he would not cert it.

PaulieBoy

2011 wrote: »

If the spur was used to feed something located in the hot press like a shower pump then you would be ok. For a TV, no he would not cert it.

Then it should not be done, simple!
And anyone who advises so is advising someone to do something which is deemed wrong, and putting them outside of the regs, and on unsafe ground.
The playground of the ignorant and simple.

2011

Then it should not be done, simple!

That is my point, yes. Having said this it would be considered a more minor offence considering what happens in the real world.