Real Life Customer Enquirer

[happysteve]

Just wondering aloud... There are a few things to think about here but I will just pick one of them.

I wonder if, as the chap seems to think, the tails need extending, if they will end up being longer than 3m? I can't find a specific mention of this length in the OSG or BGB, apart from 434.3 (iv), and here it effectively says it's up to the distributor to decide. So assuming the 3m as a general guide for the length of tails that the distributor agrees will be protected by their cut-out fuse, you might need something like this:

... the ubiquitous MEM 800KMF switchfuse (or maybe summat with a slightly higher rating... immersion heater plus shower plus the usual stuff rings some alarm bells, but we'll leave that for now). And depending on the route of the cable (tails) between the cut-out and the board, you might want to think about the type of cable to use; SWA might be more appropriate.

I will leave some of the other potential issues for now, off to bed

 

[trev]

Steve you won't find any mention of that 3 metre rule in 7671 or the OSG. That's because the DNOs work to their own set of rules which are quite different from ours. In a nutshell, they don't want their cutout fuse protecting anything more than it absolutely has to so somehow, I have no idea how, they came up with some sort of compromise that it's allowed to protect up to 3m.
There's probably some logic to it somewhere but I have no idea where.

 

[pennychew]

What about mains smokes/heat detectors with it being a rental? I know it's not a requirement in older houses but if you change the cu do you need to bring those up to current standards as well?

 

[Bobster]

What about mains smokes/heat detectors with it being a rental? I know it's not a requirement in older houses but if you change the cu do you need to bring those up to current standards as well?

I'd have said no, only circuits you make changes to need bringing to current standards.

However I would be strongly recommending the client.

 

[pennychew]

But there's also an argument that says by changing the CU you are changing every circuit? I'm not great on the regs yet to be honest and there seems to be a lot that is open to interpretation! it will be interesting to see what all the opinions are?

 

[Pete999]

What about mains smokes/heat detectors with it being a rental? I know it's not a requirement in older houses but if you change the cu do you need to bring those up to current standards as well?

I think you need to ask the question as to why you are changing the CU? it's not because it's not to the 17th, its because it's in a dodgy position, but remember before you move the CU there is an important task to complete before you change it.

 

[Bobster]

But there's also an argument that says by changing the CU you are changing every circuit? I'm not great on the regs yet to be honest and there seems to be a lot that is open to interpretation! it will be interesting to see what all the opinions are?

Correct, but if there isn't already a smoke circuit. Have you changed that?

 

[trev]

Isn't the rule taken from Part P? "All new and refurbished properties will have mains powered smoke alarms......."
Changing a CU does not imo constitute a refurb.

 

[pennychew]

I think you need to ask the question as to why you are changing the CU? it's not because it's not to the 17th, its because it's in a dodgy position, but remember before you move the CU there is an important task to complete before you change it.

Get the kettle on before you knock the juice off? [emoji2]

Just kidding!

 

[pennychew]

Isn't the rule taken from Part P? "All new and refurbished properties will have mains powered smoke alarms......."
Changing a CU does not imo constitute a refurb.

To be honest I thought it was just for rentals but I've never read it anywhere, just remember hearing it

 

[Bobster]

To be honest I thought it was just for rentals but I've never read it anywhere, just remember hearing it

As I have never undertaken work in a domestic property, knowing rules like this is unnecessary for me. Sounds like it could be just on of those 'good practice rules'.

 

[pennychew]

I think you need to ask the question as to why you are changing the CU? it's not because it's not to the 17th, its because it's in a dodgy position, but remember before you move the CU there is an important task to complete before you change it.

To be honest other than the normal set of tests you would carry out to confirm all circuits will be compatible with the new CU and rcd I can't really think of anything out of the ordinary?

I would question if it really needs moving at all as like someone has already posted I wouldn't be paying to have a CU moved in a house I was renting anyway especially when it works fine as it is.

 

[Simonslimline]

Pretesting to highlight any issues is definitely a must. Not forgetting to test for borrowed neutrals as well.

 

[Pete999]

Pretesting to highlight any issues is definitely a must. Not forgetting to test for borrowed neutrals as well.

Nice one, good thinking matey

 

[trev]

There's a few more pre change tests to be carried out too. Well at least I do em.