does this comply?

[Nicky Tesla]

This brings another scenario into it with lighting circuits saying that it uses the reg to supply light fittings which are unlikely to create an overload.http://download.hager.com/hager.uk/files_download/guides/klik_knowledge_is_power.pdf

 

[ADS]

Absolutely superb, Nicky.

For anyone who can't be bothered reading the link, here's the appropriate text:

Q How can you use a 16 A circuit breaker when the LSC plug and flexible cord are rated at 6 A?

To best answer this, we need to split the question into three parts.

Firstly, how is overcurrent defined?

Overcurrent is defined as overload currents or fault currents.

Second, how do you define overload current?

Overload current is an overcurrent occuring in a circuit that is electrically sound.

The designer needs to decide if a circuit is liable to carry overload current.

Finally, can overload protection be omitted?

There are some conditions where overload protection is not necessary. Regulation 433.3.1 (ii) tells us that overload protection is not necessary for a conductor, which, because of the characteristics of the load, is not likely to carry

overload current.

And so, answering the original question, when overload current protection is not required the nominal current of the protective device can be greater than the current carrying capacity of the flexible cord.

 

[ianmacd]

Yes thats flexible chord that will always be in free air or clipped to a wall not t&e that could be running through >100mm of insulation.

 

[ADS]

A thought for the people who believe the ops scenario doesn't comply.

You turn up to do a PIR on a property and come across the ops scenario with no spare ways in the CU.

What do you do?

Tell the customer that it fails as it doesn't comply with BS7671 and advise swapping the 32A RCBO for a 20A.

The customer says

"That won't work, mate, I've got a fixed load on my FCU drawing 10A, and the equipment plugged into the double socket draws 10A each.

That gives a design current of total 30 amps off the RCBO, a 20A one will keep tripping:|"

What do you do now?

Tell the customer that the 2.5mm cable isn't suitable and you'll have to rip the premises apart and replace it with 4mm.

Customer says

"Each 2.5mm cable can carry up to 27A, neither cable is carrying anywhere near that, I'm not happy with your recommendation."

So what? You fail a perfectly safe and compliant installation. Get a life

 

[ianmacd]

Just because it fails to comply with 7671:2008 doesn't mean it doesnt comply with an older version. This is a new installation so does not comply. Simple as!

 

[ADS]

Thread title - Does this comply?

32A RCBO feeding two 2.5mm cables with a switched fused spur or single socket on the end. So one point per cable. I think yes, but i was told different today and i think they are wrong.

No mention of what type of installation it is - just 'Does it comply?'

 

[ianmacd]

Thread title - Does this comply?No mention of what type of installation it is - just 'Does it comply?'

So the answer is need more info to start with unless a yes/no is required then its no as you can't even tell if the 2.5 will be able to carry 26A you claim is the maximum load.

 

[steptoe]

A thought for the people who believe the ops scenario doesn't comply.You turn up to do a PIR on a property and come across the ops scenario with no spare ways in the CU.

What do you do?

Tell the customer that it fails as it doesn't comply with BS7671 and advise swapping the 32A RCBO for a 20A.

The customer says

"That won't work, mate, I've got a fixed load on my FCU drawing 10A, and the equipment plugged into the double socket draws 10A each.

That gives a design current of total 30 amps off the RCBO, a 20A one will keep tripping:|"

What do you do now?

Tell the customer that the 2.5mm cable isn't suitable and you'll have to rip the premises apart and replace it with 4mm.

Customer says

"Each 2.5mm cable can carry up to 27A, neither cable is carrying anywhere near that, I'm not happy with your recommendation."

So what? You fail a perfectly safe and compliant installation. Get a life

yes, unless you are willing to put your name to an uncompliant installation,

and you wonder why I get wound up about 5week****ingwonders ,

and unless his double socket is rated at 26Amps then this is yet more BS, skt outlets are only rated at 13Amps.

you are the one that needs to start letting people do their jobs properly.

 

[Badger]

yes, unless you are willing to put your name to an uncompliant installation,and you wonder why I get wound up about 5week****ingwonders ,

and unless his double socket is rated at 26Amps then this is yet more BS, skt outlets are only rated at 13Amps.

you are the one that needs to start letting people do their jobs properly.

that told him steps :Spam2 :^O shall i send brian round to his house for you :^O :^O :C

 

[Nicky Tesla]

ok steps so why are we allowed 13a rated sockets on a 32a mcb......for the same reasons we have been explaining to you since the start of this thread thats why!!! ]

 

[ADS]

I'm not even going to justify your ridiculous post with an answer.

 

[Graham Lister]

yes, unless you are willing to put your name to an uncompliant installation,and you wonder why I get wound up about 5week****ingwonders ,

and unless his double socket is rated at 26Amps then this is yet more BS, skt outlets are only rated at 13Amps.

you are the one that needs to start letting people do their jobs properly.

Yet another wind up post from steptoe. What has this got to do with 5 week wonders? Hate to say it but from reading many posts on here by steptoe it seems he cant back up any of his opinions. The above statement illustrates this point perfectly. To say a 13A socket outlet is not suitable for use on a breaker rated at 32A is nonsense. To start abusing people as 5 week wonders is also a bit sad.

 

[kme]

Although Albert may not be as eloquent as some members on here, I will vouch for his knowledge of these things. They may not be perfectly phrased, but he DOES know his stuff.

Perhaps not dismissing him as a "wind-up" would be a better course of action.

 

[ADS]

Yet another wind up post from steptoe. What has this got to do with 5 week wonders? Hate to say it but from reading many posts on here by steptoe it seems he cant back up any of his opinions. The above statement illustrates this point perfectly. To say a 13A socket outlet is not suitable for use on a breaker rated at 32A is nonsense. To start abusing people as 5 week wonders is also a bit sad.

We just have to count ourselves lucky, Graham, that the Ops example of two 2.5mm radials on a 32A RCBO aren't connected in a consumer unit in a shed with an exported TN-C-S earthing system.......he'd be laying an egg!! ROTFWL

 

[Graham Lister]

Although Albert may not be as eloquent as some members on here, I will vouch for his knowledge of these things. They may not be perfectly phrased, but he DOES know his stuff. Perhaps not dismissing him as a "wind-up" would be a better course of action.

You may know him I dont. I was taking his posts as I see them. The five week wonder comments are directed at all on this thread who disagree with him. If he can only back up his argument with posts like that then its probably best he doesnt bother in future. I thought this was meant to be a helpful forum not one to insult people who may have a different viewpoint.

For him to say a 13A socket outlet cannot be used on a 32A breaker is nonsense. Does he wire all his domestic stuff with 32A commando sockets? For him to say that must be a wind up or is it just me?

 

[Nicky Tesla]

just a quick reminder......the above scenario is only ok if the pfc is low enough to accommodate the MCB. The manufacturers data sheets for let through energy need to be observed. opcorn

 

[Nicky Tesla]

ooh! look iv found something else useful. It shows below 3Ka pfc 1.5 cpc in 2.5t&e is ok, but above this up to 6Ka pfc a 2.5cpc needs to be used. So t&e is no good, but singles in conduit will still be ok. ?:|

 

[Nicky Tesla]

oops forgot to put the link in [http://www.theiet.org/publishing/wiring-regulations/updates/osg2008errata.cfm?type=pdf

 

[Nicky Tesla]

4 posts in a row....looks like im talking to myselfROTFWL

 

[Graham Lister]

Nicky I have a feeling no matter how much you prove there is no danger of a bit of 2.5mm on a 32A breaker with overload protection downstream some people will not accept it. Possibly would even be code 1 for some people.

The greatest obstacle to discovery is not ignorance -- it is the illusion of knowledge.