Main incoming cable 10mm

[Don777]

Hi can some one explain in simple English I have incoming main power cable 10mm to my 100amp fuse then to meter I'm adding aditional concumer unit to outbuilding with total appliances usage off 22kW electrician suggested 25mm armoured cable from Henley block running to outbuilding .Q how does this 10mm main incoming cable suport My house and addionall outbuilding witch will be on 25mm or do I need call power supplier to change main incoming cable ? Confuced.com little bit This similar layout of cables in my meter box View media item 55438

 

[bernardgreen]

Is that cable 10mm diameter ?

If so the conductor inside the insulation is probably about 8 mm diameter

That means it has a cross sectional area of 50 square mm

Area = pi × r2 with pi = 3.141592653589793

Edit r2 should be r squared

 

[Chri5]

What will you be doing in the outbuilding?

How far is the outbuilding away?

The cable suggested is pretty lumpy for a shed. Have a think about the uses in the outbuilding for electric and see if there's value in having such a large feed.

I take it you intend to fit a switch fuse and run off that?

 

[ban-all-sheds]

What makes you think that your service cable has 10mm² conductors?

Anyway - you may have appliances which total 22kW, but you will not be using all of them at once, so the load will never be 22kW.

http://www.tlc-direct.co.uk/Book/6.2.1.htm

How far away is the outbuilding? I wonder if you need 25mm² cable because of voltage drop.

What kind of outbuilding is it? How does it come to have 22kW worth of appliances in it?

The DNO will not replace the service cable, and if they did you could not afford it.

 

[ban-all-sheds]

Edit r2 should be r squared

Like this, you mean?

Area =Πr² with Π = 3.14

 

[westie101]

Looks like a 16mm2 plain concentric to me, with a loop to an adjacent property.
That's good for 100A so I wouldn't worry.

 

[Don777]

What will you be doing in the outbuilding?

How far is the outbuilding away?

The cable suggested is pretty lumpy for a shed. Have a think about the uses in the outbuilding for electric and see if there's value in having such a large feed.

I take it you intend to fit a switch fuse and run off that?

. Yea the will be switch .Sauna 9kw power shower 8.5kw tumble dryer 3kw, washing machine,wall heater ,lights and sockets its 25 meters way

 

[ban-all-sheds]

So will the sauna be going flat out at 9kW at the same time the shower is being used and someone is washing one load whilst drying the previous?

 

[Don777]

So will the sauna be going flat out at 9kW at the same time the shower is being used and someone is washing one load whilst drying the previous?

. Well not always but it will be at the times

 

[westie101]

You do know that for that increase in fixed load (the sauna & the shower) you DO have to notify your DNO and get their clearance to connect it! (as defined by your terms and conditions of supply)
They will check the incoming service cable size as part of the process.

If you connect it and it then causes problems the DNO has the power to require you not to use the equipment, failure to comply with this could see your supply disconnected!

Just to add, it is doubly important that you get DNO approval, as with it probably being a "master" service with a loop to an adjacent property, there is a risk at the adjacent property of voltage problems and/or flicker problems when switching the larger fixed loads.
This alone would render you liable to sanctions from the DNO under ESQCR

 

[JohnW2]

You do know that for that increase in load (the sauna & the shower) you DO have to notify your DNO and get their clearance to connect it!

As a matter of interest, have you any idea how often people actually do notify DNOs in such circumstances? I've only really ever heard of it being done when people have been installing semi- (or not so semi-!) 'industrial' equipment - never in relation to loads which sound/feel 'domestic'.

Kind Regards, John

 

[westie101]

As a matter of interest, have you any idea how often people actually do notify DNOs in such circumstances? I've only really ever heard of it being done when people have been installing semi- (or not so semi-!) 'industrial' equipment - never in relation to loads which sound/feel 'domestic'.

In a fairly low percentage of the time nowadays, to be honest. It is something that electrical contractors should advise on (well they all used to anyway) but most no longer do so!
There is however a clause in the National Terms of Connection to cover it.

http://www.energynetworks.info/storage/NTC for Connection Terms website_3Nov11.pdf

Network constraints. Our obligations under this agreement are subject to the
maximum capacity and any other design feature of the connection. You must contact
us in advance if you propose to make any significant change to the connection or to
the electric lines or electrical equipment at the premises, or if you propose to do
anything else that could affect our network or if you require alterations to the
connection.

Ok it could be said to be fairly woolly in it's language, but it or something similar has been around for a lot of years!


So a question to all the electricians on here: - do you advise your clients to apply for additional fixed loads?

 

[JohnW2]

As a matter of interest, have you any idea how often people actually do notify DNOs in such circumstances? I've only really ever heard of it being done when people have been installing semi- (or not so semi-!) 'industrial' equipment - never in relation to loads which sound/feel 'domestic'.

In a fairly low percentage of the time nowadays, to be honest. It is something that electrical contractors should advise on (well they all used to anyway) but most no longer do so!

Needless to say, that's exactly what I expected.

There is however a clause in the National Terms of Connection to cover it.
http://www.energynetworks.info/storage/NTC for Connection Terms website_3Nov11.pdf

Network constraints. Our obligations under this agreement are subject to the maximum capacity and any other design feature of the connection. You must contact us in advance if you propose to make any significant change to the connection or to the electric lines or electrical equipment at the premises, or if you propose to do anything else that could affect our network or if you require alterations to the connection.

Ok it could be said to be fairly woolly in it's language, but it or something similar has been around for a lot of years!

Fair enough - but, quite honestly, it' so 'wooly' that I find it hard to believe that a significant proportion of consumers would have a clue as to what, if anything, it required them to tell/ask a DNO about. I wouldn't mind betting that, despite those terms, the great majority will probably assume that it does not apply to any 'ordinary domestic loads',even if multiple (e.g. several electric showers!)!

So a question to all the electricians on here: - do you advise your clients to apply for additional fixed loads? [/b]

Interesting question - but I suspect I know the answer that most would give (if being honest!).

Kind Regards, John

 

[DetlefSchmitz]

I would have thought that most people would think that, having been give a 100A fuse, they could draw up to 100A without asking for special permission.

 

[JohnW2]

I would have thought that most people would think that, having been give a 100A fuse, they could draw up to 100A without asking for special permission.

Definitely, IMO. Just, I fear, as they will think that they can draw 2x13A from a double socket!

Kind Regards, John