earthing of hot tub

[taza]

hi all

i have a job of installing an external supply for a hot tub.
i am yet to look at the job but over the phone he has said that it needs a 16 amp supply.
my plan is to install a 20 amp mcb (or rcbo if not rcd protected) and run a 2.5mm t&e radial to a weatherproof 16 amp commando socket mounted on the wall directly off the house. do i need to allow for any kind of extra earthing etc should it perhaps be a c type breaker for the startup of the pumps?

i have not seen any paper work for the tub as of yet.

cheers

 

[telectrix]

Best to read manufacturers installation guide. it should tell you all you need . e'g' if any special earthing arrangements are necessary.

 

[taza]

if it requires a separate earth how would i go about this? keep the cpc from the twin and earth separate. and then run a separate earth to an earth stake.
cheers

 

[leeweimaraner]

make sure it is a dedicated supply for the hot tub?protected by rcd 30ma the hot tub will then be earthed through the plug on hot tub????

 

[telectrix]

first, read and see what is required. no use jumping the gun.

 

[taza]

yeah that was my original thinking!
but after reading some different threads about hot tubs on here, and people getting shocks and seperate earthing etc, got me bit worried

 

[taza]

yeah probably right just wait until i go and look at the job end of the week and go from there.
just wasn't sure if there was a general theme with hot tubs. never done one before.
cheers guys

 

[telectrix]

connect it up. throw a squirrel in the tub. testing complete!

 

[taza]

if only was that simple ha just starting out after an apprenticeship so want to get it right.
something completely irrelevant... how do you stop the emails that come through every time you get a reply?

 

[telectrix]

go into one of the emails, block sender.

 

[IQ Electrical]

yeah probably right just wait until i go and look at the job end of the week and go from there.
just wasn't sure if there was a general theme with hot tubs. never done one before.
cheers guys

The general theme is to TT the supply at the load end, depending on the earthing system present, the distance from the house and as Telectrix said, the manufacturers instructions.

The problem is that you are stepping out of the tub with a very low body resistance, often onto true earth, thus possibly risking any potential difference between true earth and the Main Earth Terminal of the installation.
The only way to remove such a potential difference is by way of a TT system local to the tub.

 

[taza]

how would i go about that? just stick the cpc in a connector inside the commando socket and then an earth rod off of the earth terminal?
and how would you test and record these results,
thanks

 

[IQ Electrical]

how would i go about that? just stick the cpc in a connector inside the commando socket and then an earth rod off of the earth terminal?
and how would you test and record these results,
thanks

There isn't a one size fits all solution but we normally fit an IP65 consumer unit with a rotary isolator for the hot tub, also a twin socket for any lighting or music that the client may wish to use.

Toolstation > Electrical > MK Consumer Units > MK Shower Consumer Unit IP65

Toolstation > Electrical > IP55 Rated > Socket IP55

20 Amp TP&N Rotary Isolator Insulated Weatherproof - IP65

Obviously the current ratings etc. in the images are just as I copied them and I am not saying that every hot tub installation has to be this way, some of it is preference!

 

[blackiel]

Youre right,there isnt a one fits all...but cheers for the links...ive come across two now,run off 13a plugs,from a double socket in a conservatory,been told it aint harmed them yet....thank the electric stars for ignorance...!!!

 

[Deleted member 9648]

It's classed as a swimming pool....the requirements of section 702 apply.