Thanks PC. I am thinking of using a 2P&E interlocked 32A switched socket on the outside of the shed. This is (I hope!) IP44. I was considering normal 4mm2 flex routed in conduit along the edge of the decking purely as protection. Is my socket idea ok though?
Jacuzzi/Hot tub isolation
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Why a socket? The spa is a piece of fixed electrical equipment. It's not going to get moved around!! And it needs to run 24/7. Or do you think they might want to plug other equipment into this socket? And frankly I think a commando socket will look a lot more out of place than a rotary isolator in a domestic garden.
---------- Post Auto-Merged at 21:06 ---------- Previous post was made at 20:59 ----------
I'd also stick with H07RN-F rather than PVC covered flex. The rubber sheath (N) is much tougher, waterproof, UV, heat and oil resistant (so also great for connecting hobs and ovens). It also has a higher ccc compared to PVC/PVC.
---------- Post Auto-Merged at 21:07 ---------- Previous post was made at 21:06 ----------
And don't forget your cord end ferrules (as required by the regs!)
---------- Post Auto-Merged at 21:06 ---------- Previous post was made at 20:59 ----------
I'd also stick with H07RN-F rather than PVC covered flex. The rubber sheath (N) is much tougher, waterproof, UV, heat and oil resistant (so also great for connecting hobs and ovens). It also has a higher ccc compared to PVC/PVC.
---------- Post Auto-Merged at 21:07 ---------- Previous post was made at 21:06 ----------
And don't forget your cord end ferrules (as required by the regs!)
Thank you all for your excellent advice.
I have redesigned my ideas around some of the comments and propose this.
PME supply to house. 10mm2 3-core armoured from house fuseboard to shed on 50A RCBO. (Design based on a design load of 11kW for 30m length.) New standard 4-way CU in shed. 16mm2 main earth to a rod. Circuits in shed: 32A jacuzzi, 20A double socket, 6A supply to Wise Box switching 10 no. LED decking lights and 2 no. 150W floodlights mounted on the side of the shed, 6A for internal shed light. 32A AC22 rotary isolator mounted on outside wall of shed facing jacuzzi approx. 5m away. Allowed 8m x 4mm2 3-core SWA from RI to jacuzzi. Pack of 10 60mm decking lights plugged in to single socket in shed wired from WiseBox. Socket labelled accordingly. I am pricing job based on this so any suggested changes would be welcome before I finalise and email the quote tomorrow.
Thanks again.
I have redesigned my ideas around some of the comments and propose this.
PME supply to house. 10mm2 3-core armoured from house fuseboard to shed on 50A RCBO. (Design based on a design load of 11kW for 30m length.) New standard 4-way CU in shed. 16mm2 main earth to a rod. Circuits in shed: 32A jacuzzi, 20A double socket, 6A supply to Wise Box switching 10 no. LED decking lights and 2 no. 150W floodlights mounted on the side of the shed, 6A for internal shed light. 32A AC22 rotary isolator mounted on outside wall of shed facing jacuzzi approx. 5m away. Allowed 8m x 4mm2 3-core SWA from RI to jacuzzi. Pack of 10 60mm decking lights plugged in to single socket in shed wired from WiseBox. Socket labelled accordingly. I am pricing job based on this so any suggested changes would be welcome before I finalise and email the quote tomorrow.
Thanks again.
- RCD protection to TT systems needs to be double pole in my book
- I'm not keep on RCD protetcing the Sub-main, why not RCD protect at the board in the shed
- If you are dropping the earth at the far end and TTing, then 3core is a waste of copper, 2core is all you need.
- I'm not keep on RCD protetcing the Sub-main, why not RCD protect at the board in the shed
- If you are dropping the earth at the far end and TTing, then 3core is a waste of copper, 2core is all you need.
Why the RCD protection on the PME side??
Why not in the shed?
Why not in the shed?
are you TT'ing the shed or do you propose in localising the 'PME' install?
as I asked previously, is it actually PME or simply TNCS ?
as I asked previously, is it actually PME or simply TNCS ?
Hi Noz. Good to see you on here mate. Well, I could make the shed board 30mA RCD main switch. I wasn't sure whther to RCD the sub-main. Would the shed end be best then? 2-core 10mm2 from the house on normal 50A mcb.
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tbh mate I really don't know. In some respects I would dearly love to use the house earthing to avoid TT but I can't be certain that it isn't PME. Just playing it safe. I have spent a lot of time on this and keep going around in circles. Thought I'd got it battened down. What do reckon?
you could test the Ze/Ra to check,
do you have a means to test Ra?
if not then best to play it safe as its NOT PME and simply TNCS
do you have a means to test Ra?
if not then best to play it safe as its NOT PME and simply TNCS
Not with you, sorry being thick. I can test the Ze at the house but will just do a Ze "loop" style test on the rod as I dont have special kit for the Ra. Is this what you meant?
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Also ( ] ) I have assumed that TN-C-S and PME are one and the same. I didn't know there was a difference. ; \
---------- Post Auto-Merged at 22:14 ---------- Previous post was made at 22:12 ----------
Also ( ]
) I have assumed that TN-C-S and PME are one and the same. I didn't know there was a difference. ; \
Un,
If it's a TN supply and you're using SWA then there will not be any requirement to RCD the sub main, just the final circuits (if required).
If it's a TN supply and you're using SWA then there will not be any requirement to RCD the sub main, just the final circuits (if required).
earthing systemsNot with you, sorry being thick. I can test the Ze at the house but will just do a Ze "loop" style test on the rod as I dont have special kit for the Ra. Is this what you meant?---------- Post Auto-Merged at 22:14 ---------- Previous post was made at 22:12 ----------
Also ( ]
note the subtle difference between PME and TNCS
without suitable test kit for doing an Ra test you cant really be sure you have PME so in that instance I would treat it as simply TNCS and TT the outside supply at the shed.
hope that is of help to you.
I nearly added that to my post TBH, and I do prefer my RCD protection only on the final circuits if I can get away with it
Even if you RCD at the submain source (TN) you'll still have RCD protection for the TT'd circuits... Might look a little odd, but it will be there
Even if you RCD at the submain source (TN) you'll still have RCD protection for the TT'd circuits... Might look a little odd, but it will be there
Along with the inconvenience of having to walk freezing and soaking all the way to the house to reset it, when it trips and you are in the hot tub.
Minimise inconvenience in the event of a fault?...
Minimise inconvenience in the event of a fault?...
Ive always thought you wouldnt get discrimination with breakers close (rating) anyway, so the same effect. And a wet person turning poking around in a fuseobard in the possible vicinity of the fault, doesnt sound brill to me. At least if they have to go back in they might be dry first! the minimise inconvenience reg is a bit woolly, a short walk isnt too much of a hardship. Just my thoughts.
Anyway the only reason I mentioned it was I thought the OP got the impression there was something wrong with what he was suggesting. Which I didnt think there was, just a preference from noz to do it a different way, which he cleared up.
Anyway the only reason I mentioned it was I thought the OP got the impression there was something wrong with what he was suggesting. Which I didnt think there was, just a preference from noz to do it a different way, which he cleared up.
well if the RCD trips, then its probably a faulty hot tub, so i wont really matter if the RCD is in the shed at arms reach away, or in the house. although if its in the house they will get a little more exercise
David Haden8100
Member
Certain two facts on this post unequivocally the best we have all had.I'm totally agree with you.You'r 100% good here that if the RCD trips, then its probably a faulty hot tub.
I'm looking at doing a similar job next week or so and having discussed requirements with hot tub company they initially said it required a 6mm supply cable, apparently the hot tub actually requires 16a to run
On my job there is no shed but there is a two level decking area( hot tub site Is In lower)
My thoughts are to run 4mm sy to decking area approx 20m from house, new 2way db being installed as no spare ways on existing, customer wants install to be separate from house electrics.
I have asked for an access hatch in side of the higher level deck to house all my cables( customer also likes the idea to hide away other garden things when not in use)
My idea is basically a foot sq 'door' secured with screws customer has decided a three foot by one foot door would be handier for him!
I'm using a large gwiss style weather proof box to house a wise switching unit via a fused spur inside box to power decking lights, wall lights and 'mood' lights around hot tub (basically lights you can see all the good stuff going on if your in the tub but not bright enough for the neighbours to video it!)
For isolation of hot tub the company has asked for it to be placed approx 2-3m from hot tub
I'm using a rotary isolator with built in 'commando ' style female plug
Cable from hot tub is supplied with male end for instant connection/disconnection
I've used this idea before and it worked sweeter than a big bag of sweet things
On my job there is no shed but there is a two level decking area( hot tub site Is In lower)
My thoughts are to run 4mm sy to decking area approx 20m from house, new 2way db being installed as no spare ways on existing, customer wants install to be separate from house electrics.
I have asked for an access hatch in side of the higher level deck to house all my cables( customer also likes the idea to hide away other garden things when not in use)
My idea is basically a foot sq 'door' secured with screws customer has decided a three foot by one foot door would be handier for him!
I'm using a large gwiss style weather proof box to house a wise switching unit via a fused spur inside box to power decking lights, wall lights and 'mood' lights around hot tub (basically lights you can see all the good stuff going on if your in the tub but not bright enough for the neighbours to video it!)
For isolation of hot tub the company has asked for it to be placed approx 2-3m from hot tub
I'm using a rotary isolator with built in 'commando ' style female plug
Cable from hot tub is supplied with male end for instant connection/disconnection
I've used this idea before and it worked sweeter than a big bag of sweet things
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