Workshop power

Confused but learning · Apr 2, 2021

Hello can anyone offer and advice on running power to an workshop. All work will be done by a professional electrician, I am merely seeing if my idea is feasible. So far I have 6mm swa prysmian cable buried according to reg, sand bedded and warning tape over etc 6.5 metre run.
I have recently had a new electric oven installed which is 240v 2075w. I have an unused switched supply on the kitchen ring main for an old baseboard heater.
Would the following be possible, connect the over to the unused 13amp switch, use the oven supply which is a 32amp supply with a dedicated rcd in the main panel to power the workshop?
The total distance for the shed including the existing cooker feed is 16 meters.
I am planning to run the trunking for the internal cable when I rip out the kitchen.
As I said I will not be doing any of the electrical work and will get a professional electrician to do it but wanted to know if the concept will work or if I am missing something obvious.

Soi disant · Apr 9, 2021

Pete999 said:
Agree but many Electricians want the rules and regulations in black and white,

Ah - but what's to be done when you show them black words on white paper and they can't tell the difference between "must" and "should", or "normative"and "informative"?

David Anthony · Apr 10, 2021

Soi disant said:
Ah - but what's to be done when you show them black words on white paper and they can't tell the difference between "must" and "should", or "normative"and "informative"?

Send them off to get a left hand screwdriver and a tin of current

DefyG · Apr 10, 2021

David Anthony said:
Send them off to get a left hand screwdriver and a tin of current

Dont jest, this website has 3922 of them apparently ?

David Anthony · Apr 10, 2021

DefyG said:
Dont jest, this website has 3922 of them apparently ?

View attachment 84449

Found this

https://img1.accu.co.uk/news/Right-Hand-Left-Hand-Thread.jpg

pc1966 · Apr 10, 2021

David Anthony said:
Found this

Or some cool, but slightly pointless, example of Russian engineering curiosity:

pc1966 · Apr 10, 2021

I sometimes wonder why folks get so worked up about the "2kW fixed load" thing.

We all know the RFC is quite robust and tolerant of most things and many houses have (or had) practically everything bar the lights & cooker on a single RFC. Quite often folks would have a couple of 3kW heaters and the usual washing machine, tumble dryer, etc, in use and no problems.

Putting significantly more than 13A on at a point on the RFC is getting in to suspect territory as you can't be sure of how well the currents in the two "legs" are going to balance, but we have few loads that come in to that area. Probably just wired-in cookers, heating showers, or an EV charger in recent year or two, and they would normally be on separate radials anyway.

The only odd one I can think of is the old immersion heater, less popular these days due to combi boilers and instant-heat showers, as they would typically be around 3kW and could be heating for an hour or more easily. So were they the motivation for saying fixed loads above 2kW, and not the 3kW of a 13A socket?

Also the argument for putting something on to a separate circuit goes beyond the basic aspect of circuit protection alone, there is also the "good engineering" aspect of minimising inconvenience/risk under fault conditions to allow the fault to be isolated with the least collateral damage. I guess a number of "fixed loads" come in to this sort of territory, especially water heaters, where you would want to be able to keep any faults from taking out all/half of the house socket outlets as well.

brianmoooore · Apr 10, 2021

pc1966 said:
I sometimes wonder why folks get so worked up about the "2kW fixed load" thing.

Quite often folks would have a couple of 3kW heaters and the usual washing machine, tumble dryer, etc, in use and no problems.

This is exactly why! The above may well work on a single RFC with no problems in practice, but if there's a 2kW+ fixed load as well, that will likely take it over the edge.