Garage power (high load)

[Kyran]

Hi All


Any other thoughts, ideas/whys of legally doing it. I have client that wants to rewire his large/double garage as he wants to put his kilm and potters wheel in it plus run whats there and power for a new electric garage door (13a plugged one). currently theres lights, fridge/freezer power down to green house running heater.


So he want to power
kilm 3kw
potters wheel 400w
minimim heater 1 kw for him self
fridge/freezer
lights
garage door
green house heater.


He currently has a 2.5 t&E fuse down off his living room ring.


What i have quote to run a 6mm from a new supply (split tails) due to old board that is currently there. Garage CU in the garage that would run 6 10w led floods, 6 sockets around different parts of the garage, three circuits. intergreat the green house power in to new board. all cabling in conduct. The garage is 7m by 5.3m wide the 6mm armoured is about 20m long.


He does not want to pay to do and want to to requite to take the power off the ring, which i have said its to much and he would end up running out of power as the kiln takes to 3kw and even if you just have the kiln and fridge it will blow.


Any other ideas.

 

[telectrix]

He does not want to pay to do and want to to requite to take the power off the ring

he's a muppet . your plan looks sensible, as long as the calcs. work out OK. split tails and fit a 40A KMF to supply the 6mm.

 

[Kyran]

Thats what i thought, and thats what i was doing to do. to run the 6mm i would have to crule around under the house and install the new board as the intake in in the centre of the house. and has a coulpe of old boards of it so a new one would be the only choice. i was going to put the kilm on its ring/differnt to the fridge green house heater and garage door any way

 

[Gardner]

How does on calc those loads? I take diversity would not come into play?

 

[telectrix]

another point to bear in mind is that if you split tails, you need to fit a D/P isolator between the meter and the henleys, in order to provide a single point of isolation for the whole installation.

 

[Gardner]

another point to bear in mind is that if you split tails, you need to fit a D/P isolator between the meter and the henleys, in order to provide a single point of isolation for the whole installation.

Can a TN-C-S supply skip DP idolator?

 

[telectrix]

NO. single point of isolation, whatever the earthing system.

 

[sparksburnout]

NO. single point of isolation, whatever the earthing system.

IEE Guidance Note 2 - "Isolation & Switching", p.40

"It is permitted for a dwelling to have more than one electrical installation. Therefore one 'main switch' is not required to isolate all consumer units simultaneously provided the consumer units have an integral main switch.

"This situation frequently occurs when an additional consumer unit is added, e.g. to supply an electric shower. Regulation 537.2.2.6 requires each device used for isolation to be clearly identified by positional or durable marking to indicate the installation it isolates."

 

[Octopus]

Quote for the "proper" job - if the client isn't happy with your quote - don't compromise. The client is a MUG

 

[telectrix]

IEE Guidance Note 2 - "Isolation & Switching", p.40

"It is permitted for a dwelling to have more than one electrical installation. Therefore one 'main switch' is not required to isolate all consumer units simultaneously provided the consumer units have an integral main switch.

"This situation frequently occurs when an additional consumer unit is added, e.g. to supply an electric shower. Regulation 537.2.2.6 requires each device used for isolation to be clearly identified by positional or durable marking to indicate the installation it isolates."

i stand corrected. it's what i was told many years ago and have not questioned it.

 

[davesparks]

IEE Guidance Note 2 - "Isolation & Switching", p.40

"It is permitted for a dwelling to have more than one electrical installation. Therefore one 'main switch' is not required to isolate all consumer units simultaneously provided the consumer units have an integral main switch.

"This situation frequently occurs when an additional consumer unit is added, e.g. to supply an electric shower. Regulation 537.2.2.6 requires each device used for isolation to be clearly identified by positional or durable marking to indicate the installation it isolates."

But sadly people seem to ignore the requirement for clear identification where multiple main switches exist.

 

[Andy78]

i stand corrected. it's what i was told many years ago and have not questioned it.

It's quite correct what you believe as reflected in 537.1.4
A main linked switch or linked circuit breaker shall be provided as near as practicable to the origin of every installation as a means of switching the supply on load and as a means of isolation.

Just because the guidance gives permission to define an installation as any assembly of circuits, and that multiple installations may exist within a dwelling or building thus mangling regulation 537.1.4 into meaninglessness does not mean it's the best course of action to take.

Always best to have a single main isolator in my book too Tel. If it's a single DB then the main switch is fine. If it's Henley blocks with multiple DBs then I'd like an isolator before the split tails.

 

[DPG]

Labelling switches takes the fun out of things Daz

 

[Andy78]

Labelling switches takes the fun out of things Daz

But labelling them incorrectly puts the fun right back in again. I had an hour's worth of "fun" this morning trying to work out where a circuit emanated from.

 

[Dave OCD]

But no one in their right mind would expect the main switch on CU 'A' to isolate circuits fed from CU 'B' and so on....
Obviously it goes without saying that all circuits should be clearly labelled and IMO simply having labels that state 'sockets' or 'lights' isn't good enough, see it all the time when there are 3 or more of each aforementioned circuit at least with no further detail.