20amp fusebox...

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thomaskennedy

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Whilst looking at dust extractors i thought i may aswell get a powerful one,this one looks quite good, but it says a 20amp fusebox is required :?

At the moment i use the standard plugs in my WS (13amp IIRC).

I'm guessing it wouldn't be clever to just hook it up and see what happens :p

So what do i have to do to get 20amps down there??, Also i suspect i'll be upgrading as time goes on, and i've often noticed some machinery is 16amp, how to you get 13, 16 and 20 amps from the usual plug sockets?

Will it cost me a fortune, and is an electricion required (forgetting about those new silly regs that tell you you cant change a lightbulb :-$ )

Ta, Tom
 
2200w / 230v = 9.56A

So it's well within scope of a 13A plug,but doesn't leave a great deal left for anything else.
My workshop has a garage consumer unit;sockets on a radial,protected by a 16A mcb,lights on a 6A mcb,whole lot protected by an RCD.
The power comes from a 15A fuse in the CU,so taking into account the number of lights I have,it leaves me just over 3KW that I can draw from the sockets - basically,everything has it's own socket,but I only tend to have one in use at any one time (so no problems)

How big is the supply to your workshop ? If you have a big enough supply,and a garage CU with a spare way,you could add a seperate circuit for 16A stuff.
Or if your supply is ok,a ring circuit can carry 32A,compared to a radial at 16A (assuming 2.5mm cable)

Unfortunately,too many variables to say anything conclusive - do you know how big the supply is/how big the cable is/how long the cable is ?
(To be safe,you need to ask an electrician - as well as to comply with Part P :cry: )
 
thomaskennedy":3dcax6uf said:
forgetting about those new silly regs that tell you you cant change a lightbulb :-$
Ha hum... You missed out the "not" at the beginning there, Tom... :whistle:

Cheers, Alf
 
Alf":1h36jogm said:
thomaskennedy":1h36jogm said:
forgetting about those new silly regs that tell you you cant change a lightbulb :-$
Ha hum... You missed out the "not" at the beginning there, Tom... :whistle:

Cheers, Alf

LOL, nope definitely wrote it right 8-[ :p

PowerTool- Thanks for the help.

unfortunately i have no idea about the cable, it's grey and about 5mm wide and about 3mm thick. It has no writing on it either. I think it'll be about 14metres long max.

From what i can follow it goes from the main fusebox that shares the power to the whole house (lights, mains etc.) to the back room in the cellar (sorry Workshop :p ).

From there it goes through another room into the first plug socket. Then it seems another wire comes out of the plug socket (same sort as before) which takes it to the other plug socket.

And thats it :cry:

Hope this is of some use :D

Ta, Tom
 
Sounds like 2.5mm twin and earth (standard for household sockets)
If the cable only goes to the two sockets,and the second socket only has the one cable going in (no cable going out) it sounds like a radial,in which case it should be on a 15A fuse or 16A MCB (miniature circuit breaker) so this is the limit of the power you can draw (about 3.5 kw)
Although if your workshop is in the house (and not a seperate outdoor building) then Part P is not such a big issue,but if not confident with electrics,I would still suggest you contact an electrician.

Good luck.
 
Tom

I'm a qualified electrician.

2.5mm cable 'I think it'll be about 14metres long max.' and 20A fuses. This is max. load allowed on the cable if enclosed in a wall or in any insulation such as loft insuloation etc.. If the cable is in fact 1.5mm (looks a similar size to 2.5 if not seen before), then you would be overating the cable by about 40%

Call in a local electrician to get professional advice , ohh, and the part P regulations are law
 
Hi sparkies!

My garage was wired before the regs.(P1)

I have a 15 mtr length 6mm 3 core cable from the house consumer unit (40amp rcb) which goes to my garage which enters a box which has a 30amp cartridge fuse which then has a ring main circuit .

How much juice can I take out of this circuit?
 
John if you start talking to professional Sparkies about ratings then you will never get a straight answer.

The rating of a particular cable varies dependant upon it's location method of fixing etc. (even down to if it is in contact with wood or brick etc.)

I dread to think how far someone who has a profound knowledge of the building guidance info. might push the heating factor to save a few pounds on a big installation.

A good indication for the average domestic situation is to be found here.

Cables in free air can handle more current safely, but note the max temperatures that these tests are talking about. I would not wish to have cables running at 90 or even 70 deg C buried in my house ceilings.

To your original question I would say that in your situation your fuse has got it covered, a ring main in 2.5 mm should be good for 32amp.
 
Thanks CHJ.

I thought I should be OK. Your comments of ceilings makes me shudder though with over 4" of insulation and those house cables buried by the loft insulators.
 
devonwoody":1yz67ah0 said:
Thanks CHJ.

I thought I should be OK. Your comments of ceilings makes me shudder though with over 4" of insulation and those house cables buried by the loft insulators.

Don't get to concerned John, it is most unlikely that any wiring in your home is stressed to these levels.

As someone pointed out to me some years ago regarding the number of sockets in a room. To meet the maximum rating of the ring then a person has got to live with the equivalent of a seven bar electric fire burning continuously, even someone not worried about the cost will get a little to warm for comfort in the average house.

Edit:Anyone interested in the sort of mess a sparky can get himself in trying to do the right thing might like to read this thread.
 
Interesting and very confusing. A few years ago I was changing the shower from a 7kw to a 9.5kw, the original shower was fed with a 6mm cable. The recommendation with the shower was for a 10mm cable (apparently the new regs :?: ) Then came the arguments calculations for length air space installation etc, the outcome was that the cable should be ok :roll: . The outcome living in an old house was that the lights would dim when the shower starts and still needed to run around to get wet. Have since dumped electric shower and now run directly of a hot water gas boiler better shower and lights :wink: :) :) . Not much use for running woodworking equipment but it does show problems with electricity.

Les
 
devonwoody":1vy4xvzy said:
Thanks CHJ.

I thought I should be OK. Your comments of ceilings makes me shudder though with over 4" of insulation and those house cables buried by the loft insulators.

I think in the case of Loft Insulation any increase in cable heat due to extra insulation is negated by the fact that in high summer when a loft is at it's hottest the insulation will in fact be shielding the cable.
 
les chicken":btqkit3p said:
The outcome living in an old house was that the lights would dim when the shower starts and still needed to run around to get wet.

Les

I don't think that a 10mm cable would stop this happening. What you're seeing here is the result of either a bad connection on your incoming mains side to your house or in your consumer unit or, if you are fed from a pole and a transformer, then an inadequate supply. The electricity company have a statutory duty to provide you with 240v (230?) +- 10% I believe. If this happens a lot then you should complain and they will stick a measuring device on your incoming line for a short time to check.

When we moved in the transformer on the pole was only 2kW rating !!

And if the pole is in your garden then you can charge them for the privilege!
 
waterhead37":1dhf9ck9 said:
Tom,

It really looks like overkill for your needs. I am sure there are other things that your hard earned dosh could be better spent on.

My thoughts exactly :roll:

By the time the sparkie has charged me for just knocking at the door i could have had a Workshop full of extractors :p :wink:

I've gone waaayy outa my depth here :shock:

So maybe i should get a couple smaller extractors and switch them on as and when needed?

Maybe something like this one will suffice better?

As it doesn't mention anything to do with amps and fuseboxes \:D/ :p ... I can only presume that i can "Plug 'n' Play" :twisted:

What d'ya reckon?

Ta, Tom
 
When checking the specs,it's rated 750W,so about a third of the power of your original suggestion (and less than the vacuum cleaner i have in my workshop) so yes,just plug it in and enjoy :)
 
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