Another garage wiring question

[slurrymonster]

Hello all,

I think this is my first post (but I've been lurking for ages). The wife bought me a Clarke 160TM for our wedding anniversary (she's a good-un!) so now I'm trying to wire it in. I think I've read every post on the forum about this topic and I can't seem to answer my own question....so here goes......

The facts:

Welder draw (according to manual) 16 amps
Distance from consumer unit to garage: about 30 metres

There is power in the garage already but I'm not sure what the state of the wiring is etc....and I want to use the blue 15 amp plugs to make things 'proper'. So my intention is to run a new cable from the CU (its an old-school fuse wire job, but there is a spare slot in there) down to the garage into an MCB then wire from the MCB to the 15 amp plug.

Now this is where I'm hazy:

What fuse wire to put into the CU?
What size MCB to put in the garage? 15 amp sound sensible?
and finally what size SWA........I reckon/hope 2.5mm

I looked on TLC direct's website as they have a neat little calculator for voltage drops http://www.tlc-direct.co.uk/Technical/Charts/VoltageDrop.html

and I came up with this

So what I want to know is....do people think that this is a reasonable set-up for using my shiny new welder safely.

(I'd like to point out that my father in law used to be a qualified electrician - not up to new regs though - and will be assissting me with the actual installation)

When my father-in-law spoke to a current electrician on-site they initially said to use 10mm SWA! Which the guy later reduced to 6mm SWA.

Obviously I want to keep this as cheap as possible so the smaller the cables I need the better....

If you need more info then please let me know!

Cheers

Luke

 

[madkayaker]

2.5mm is to small in my opion and i would't need two core would use 3 as that will give you a better earth this work falls under part P of building reg so must be done by a part P compitant persion

 

[Omniata]

This would be better and gives you a little "headroom"...

Would perhaps allow you to remove the current circuit if your not sure of its condition as well...

I'd maybe go for 10mm as well, although expensive you could fit a reasonable cylinder fuse in the house and a new consumer unit to the garage with a proper installation to standard...

Edit: I agree with MK on the "3" core, don't rely on the armour as the sole means to earth


Just my two penneth


Jim.

 

[brightspark]

View attachment 16962


This would be better and gives you a little "headroom"...

Would perhaps allow you to remove the current circuit if your not sure of its condition as well...

I'd maybe go for 10mm as well, although expensive you could fit a reasonable cylinder fuse in the house and a new consumer unit to the garage with a proper installation to standard...

Edit: I agree with MK on the "3" core, don't rely on the armour as the sole means to earth


Just my two penneth


Jim.

the fuse box in house has rewirable fuses .the largest cartrige fuse would be 30 amp that would fit in . 6 mm 3core would be ok to run 30 amp to a maybee 3 way consumer unit giving a 16 amp fuse for welder a 16 amp for a few sockets on a radial and a few lights on a 6amp fuse if u increase further than that to 10mm u will need a 50 amp min breaker in a switchfuse and wired into the main meter

 

[slurrymonster]

WOW the mig-welding forum rapid response unit!

Thanks for the information fellas.

So the cable that I need is 6mm 3-core SWA (sounds expensive!)

I was wondering about this Part P regulation. Would it be sufficient to have my father-in-law do the work and then have it assessed and signed off?

Thanks again for the info.

Luke

 

[madkayaker]

only if you go throgh building control and expect £200 up + VAT there is no third party certification alowed by part P

 

[malcolm]

I ran the previous version of that welder (the 155T) from a 13 amp plug for more than 10 years and it didn't ever blow the fuse. That would be a more pragmatic approach, but you do need to use a quality plug and socket else they start smelling like a train set through poor contacts. Clarke are shielding their **** with the 16 amp requirement. It's only close to an issue if you weld on max settings all the time.

For my own garage I have a 30 amp fused feed through 6mm cable from the house consumer unit that goes to a consumer unit in the garage where it can split off to lights and sockets. Worth having a consumer unit in the garage if you are going to start messing around. Mine is clearly a spur so part P doesn't apply

 

[madkayaker]

it does if the cable goes outside or is from a kitchen

 

[brightspark]

wronggggggggg a spur is fixed wiring and part p aplies. if u have a plug in system it doesnt to be honest no one is interested in gettin sumone in thats part p unless its a new build through planning anyone can do there own wiring as long as its done right and up to current spec

 

[malcolm]

Thanks for the corrections - seems part P does apply after all. The other thing is to make sure all your wiring goes in before part P was introduced. Mine really did! Honest! Definitely worth looking up and following the current specs.

 

[Omniata]

The silly thing is Part P is a regulation, not a qualification...

All the work has to meet part P and can be undertaken by anyone, if building control question it it's up to them to pay a certified electrician to inspect at their expense, not yours...

There's a member on here who has the relevant document to prove it, I'll try to get a copy, the councils don't like it being public as it's a money making enterprise for them...


It's against part P for you to pay the sparky as then they will have had to install the wiring to meet part P. If building control pay however it's their responsibility...

A very grey area...

 

[slurrymonster]

I ran the previous version of that welder (the 155T) from a 13 amp plug for more than 10 years and it didn't ever blow the fuse. That would be a more pragmatic approach, but you do need to use a quality plug and socket else they start smelling like a train set through poor contacts. Clarke are shielding their **** with the 16 amp requirement. It's only close to an issue if you weld on max settings all the time.

I'm tempted to try this, the wire currently supplying the garage comes from a little box in the house (with a cartridge fuse (15 amp) and an on/off switch on it). So I'm assuming (danger-mouse business) that the current wire (a metal enclosed concertina affair) will be at least able to take 15 amps. So the 13 amp fuse in the welder plug should protect all this.....

I know nothing of Part P.....I'd like to have the work done properly but I can't afford to pay an electrician......and I suppose if the work was completed in the changeover period between the old colours and new colours............

Sorry about the hornets nest.

Cheers again

Luke

 

[madkayaker]

Assume nothing with old wireing

 

[slurrymonster]

The silly thing is Part P is a regulation, not a qualification...

All the work has to meet part P and can be undertaken by anyone, if building control question it it's up to them to pay a certified electrician to inspect at their expense, not yours...

There's a member on here who has the relevant document to prove it, I'll try to get a copy, the councils don't like it being public as it's a money making enterprise for them...


It's against part P for you to pay the sparky as then they will have had to install the wiring to meet part P. If building control pay however it's their responsibility...

A very grey area...

I'm not sure I understand the subtleties of Part P.

I'd definitely like to have a look at that document though.

Thanks

Luke

 

[Omniata]

I'm not sure I understand the subtleties of Part P.

I'd definitely like to have a look at that document though.

Thanks

Luke

To do the wiring to a competent standard, simply put...
Not cutting corners and making sure it meets the required spec...

Easy as fish and chips really with a bit of common sense...
That's the main requirement, common sense

 

[madkayaker]

disagree with that om the main requirment is compy with the law or be prociquited

 

[brightspark]

what tends to happen is if sumones made a cockup on wiring that isnt registered they get an ispection done by a firm in the national inspection councill who provides the evidence of bad wiring . then the guy responsible is taken to court and fined a max of a thousnand pound for not been registered and a grand for the faulty workmanship . realy if the jobs up to scrach the person wont get reported anyhow : so no ones bothered laughing:

 

[slurrymonster]

Cheers again guys.

For completeness I'll put up a post saying what I finally conclude to do when I've decided it.

Very useful information here.

Luke

 

[mr migwire]

see if this clarifies part "p" lol

http://www.khace.com/electrical/buildregspartp/index.html

clear as mud

 

[Omniata]

Also, some authorities are still insisting - despite being told explicitly by the former ODPM that they must not do this - that the person doing the work should pay themselves for an inspection and test by an electrician with specified qualifications, or trade registration or scheme membership.

This means in our opinion that local authorities do not have the power to require householders to retain an electrician to test and certificate the work in accordance with BS 7671. Local authorities which have adopted such a practice should discontinue it immediately.

As mud

Again if the work is done to the required standard and meets "competent" requirements there are no issues...