Submain Query

[Electric Eales]

Hi All,
Been asker to run a submain 100m metres from origin to a shed. This shed will have a 7.5kw shower, 6kw oven, 2 x 3kw water heaters as well as general power and lighting(not much about 12 lights & 12 twin sockets)
Not sure if running 3 phase supply would make more sense? Financially and size of cable for glanding etc. Any thoughts?

Thanks

 

[somersetsparks]

Hi All,
Been asker to run a submain 100m metres from origin to a shed. This shed will have a 7.5kw shower, 6kw oven, 2 x 3kw water heaters as well as general power and lighting(not much about 12 lights & 12 twin sockets)
Not sure if running 3 phase supply would make more sense? Financially and size of cable for glanding etc. Any thoughts?

Thanks

I would say it would be essential to run three phase in order to balance them evenly. All that lot on a single phase would be poor loading/overloading of a phase if single phase was used

 

[KAS1]

First poster strikes again lol

Hi All,
Been asker to run a submain 100m metres from origin to a shed. This shed will have a 7.5kw shower, 6kw oven, 2 x 3kw water heaters as well as general power and lighting(not much about 12 lights & 12 twin sockets)
Not sure if running 3 phase supply would make more sense? Financially and size of cable for glanding etc. Any thoughts?

Thanks

 

[Electric Eales]

Ok thanks, do you think a 40amp TP&N supply would be sufficient?

 

[PEM]

That's one hell of a "shed"!! Forget the electrics think about all the other Building Regulations involved.

 

[Electric Eales]

Shed probably wasnt correct description. It is at a golf club where the groundsmen go when its raining/for tea, so they are there most of the time!!!

 

[KAS1]

Why don't you just ask for someone to do the electrical design for you

 

[somersetsparks]

Ok thanks, do you think a 40amp TP&N supply would be sufficient?

I should say work it out yourself, which you should do.
However its pretty easy

Shower approx 30A put on L1
6Kw Oven on L2
2x 3Kw water heaters on L3

Then split your sockets and lights over L2 and L3
No load exceeds 30A ish so witha 40A you have allowed 25%ish extra capacity I would say thats a pretty good sizing for what you have intended.
Now you will just have to work out cable size to accomodate for Volt drop etc. and ensure you take suitable sized earthing/bonding conductors if necessary.

 

[somersetsparks]

Just to add though, you may have to measure current on each phase when in 'normal service' and jiggle the circuits around in the db, however with the fixed loads you have I would say above arrangement would probably be the best you can do.

 

[telectrix]

or give 'em a gas bottle, gas ring and hob kettle. tell 'em to deal with it. where do these guys think they are, the ritz?

 

[GLENNSPARK]

Shed probably wasnt correct description. It is at a golf club where the groundsmen go when its raining/for tea, so they are there most of the time!!!

eh?

12 double sockets?

 

[Engineer54]

So what do these groundsmen do at the moment without all these luxuries?? What the hell do they need a 6KW cooker for, for gods sake!!

 

[kingeri]

There must be more to this than meets the eye!

Edit: This 'shed' needs it's own supply, be it single or three phase. I wouldn't be considering the submain route.

 

[Guest55]

if the golf club has a 3 phase supply then a submains to the grounds keepers hut is feasable.
applying diversity realistically its unlikely to draw more than 40A continuous.

 

[GLENNSPARK]

somethings not right here....