10mm cable power capabilities at 25m and 50m distance

[NandM]

As part of my prep for the main extension project next year, I've decided to upgrade some outbuildings to use for temp accommodation.  We currently have a 10mm armoured cable (19mm OD) from the garage to the greenhouse that I was using to power some fans. At the garage end I've just converted the armoured cable to an extension lead as a temp fix.

 

I now plan to use some of the greenhouse (4m x 4m space) as a kitchen/utility room as the house will be unliveable and would like to understand what my options are re hot water and appliances.

The UVC that we currently have will be disconnected, so I'm thinking about sticking it in the greenhouse and running it off the mains at night.   I also plan to have the dishwasher, washing machine and tumble dryer all connected in the greenhouse as well. And finally, a hob and mini-oven (or one that runs of 13amp plug).

 

At the end of the garden, approx 60m from the house and 35m from the greenhouse will be another building that will have an area to watch TV etc. and a non-electric shower (how water from UVC in greenhouse) and a saniflo toilet. We will also have one electric heater and a bunch of lights. There is an armoured power lead here also, but looks too small for the distance from house...I haven't investigated the size, but I the OD looks to be around 10mm. I'm thinking about a new cable from the greenhouse to this building.

 

The greenhouse has the highest power requirement with the current design, but what I'd like to know is what level of power would be possible without changing to a larger cable (as this is temp for 6-9 months)...and with a sparky connecting it up correctly at the house end. Would I need to ditch electric hob and oven and go LPG instead? Likewise with UVC?

[elite]

How many cores? How is it installed?

 

This is a useful calculator: https://www.tlc-direct.co.uk/Technical/Charts/VoltageDrop.html

[Alan Ambrose]

Also guide to cable sizes here: https://www.cse-distributors.co.uk/cable/power-cable/swa-armoured-power-cable.html

That also has the nominal current rating, which is a ball park for short lengths in open air, and the resistance for calculating voltage drop. (Should come up with the same results as the TLC calculator - but that doesn’t seem to be working for me atm.)

 

You really want to check the actual conductor sizes with some calipers though. In all cases you’ll fuse/mcb the house end to lower than the calculated rated current.

 

 

[NandM]

From memory it was three core, but will check tomorrow. It's partly fixed along a brick wall and then goes down under a 100mm slab for about a meter, before popping up in the greenhouse. In the greenhouse I've wired it up into an IP66 junction box and from there into a  switched RCD socket. At the house end, it's just connected via a junction box to an old extension lead I had - and this is plugged into a socket when needed....but the bodge at both ends will be fixed by a someone who knows what they are doing. 

 

I'll check out the links - thank you.

[NandM]

3 core confirmed (blue, green and yellow).

 

Looking at the TCL calc, the cable should be fine for what I have planned. This is helpful as I can buy a perm new induction hob, rather than get something temp and ebay it later.

[Alan Ambrose]

Do get the ends sorted promptly - induction hob on extension lead on indeterminate fusing is a recipe for fire.