points served

[extension15]

 

[Mr Sworld]

you better start putting warning notices on all your double sockets from now on then you pair of plonkers

I think just putting a warning notice on you would be far easier! :^O

 

[Nicky Tesla]

A 'socket outlet' is the entire socket whether it is a one or two gang design. If you read the MK specification guide you will find that they state 'maximum load' as 13A!Even the 3 way sockets are 13A maximum (they even include a 13A fuse to ensure you cannot overload the socket). By your 'logic' it should be able to handle 39A! And the four way ones could pull 52A.

Let us take the following situation. A 2-gang socket outlet is taken from a ring main as an unfused spur, the cable supplying it is T&E 2.5mm (a common situation). If you loaded that socket with 26A, then unless you are using a 'clipped direct' installation method, you will pulling more current than the cable can handle (Table 4D5). And even if it was 'clipped direct' then you are 1A below the maximum current carrying capacity of 2.5mm T&E.

Somehow I don't think the IEE will of missed that mistake! Because if they did then there is going to have to be a lot of unfused spurs being ripped out of houses up and down the country!

If you did phone up MK then I don't think the guy was laughing at me was he Nicky?

No i dont think the IEE will HAVE(not of) made a mistake only you.

1A BELOW the current carrying capacity? wots the problem with that?

If a different install method is used (Table 4D5) then the cable will need to be uprated to 4mm. whats your point?

You obviously dont bother and would put it on 2.5mm regardless by the sounds of it.

Go on keep digging, you'll be in china soon.

 

[Nicky Tesla]

I think just putting a warning notice on you would be far easier! :^O

Hello Admin can you edit mr sworlds message like you did mine cos I am deeply offended

 

[The Godfather]

Come on guys, let's be cool.

A UK electrical outlet whether it be single or double is rated 13A, however as I have already stated a double socket would be reasonably expected to supply more than 13A, depending on the load.

A modern day Washing Machine and Tumble dryer with energy rating 'B or higher are not likely to require more than 18 Amps approximately.

It would not be unreasonable to expect a modern day double socket to supply the above mentioned current, allowing for some diversity (the washing machine).

The Godfather

 

[Mr Smith]

mr tesla .

mr sworld attempted a joke .

ANY further offensive posts from any member will be removed .

mr smith .

 

[Nicky Tesla]

does this mean we can use 15A rated juction boxes on a ring then if we can use 13Amp rated sockets? :|

 

[kme]

If the ring is of standard design, with a 30 or 32A pretective device, the maximum current flowing through any section of the ring is 1/2 of the total current consumed at that time. If the protective device is a 30A mcb then, technically, there is no reason why not. However, as the next sparx there would not be aware of this 15A jb, they may install a 32A breaker, which would have the propensity to allow 16A to flow in a leg of the ring.

Therefore, I would always use a 20A jb to extend a ring (if it was safe and compliant)

KME

 

[Apache]

mr tesla .mr sworld attempted a joke .

ANY further offensive posts from any member will be removed .

mr smith .

Ooooooh Very authorative Mr Smith

 

[The Godfather]

does this mean we can use 15A rated juction boxes on a ring then if we can use 13Amp rated sockets? :|

As I've said nicky, I would reasonably expect a double 13A socket to supply more than 13A.

(Apologies again, but I can't find the exact product testing details that are applied (load and temperature testing)).

As for the JB, my boys always fit a 30A JB when performing any alteration or extension to a ring main.

Don

 

[The Godfather]

On the subject of heating I found the following article from the ASTA BEAB site, it may be worth noting that the fuse in the plug, will contribute significantly to the heating of the socket.

Overview: The rules for British Plugs - Simplified

01/02/2006

SIMPLIFIED RULES FOR BRITISH PLUGS

The British system for plugs and sockets started before World War II at a time when there was a shortage of copper for cables. The 'Ring Main' system was devised to reduce the amount of copper needed in cables inside each house or office.

The 'Ring Main' system to the socket outlets inside each house, apartment or office uses a cable with three cores - Line Neutral and Earth. The line and neutral are 2.5 mm2 and the earth is 1.5 mm2. The cable goes from the Consumer Unit (a small switchboard in each house etc) to each of the socket outlets in turn and then back to the Consumer Unit and connected to the start of the cable - in parallel. The power can go either way round the 'Ring Main'. The plugs and sockets used must comply with British Standard BS1363 or its equivalent in Hong Kong, Malaysia, Singapore etc.

The protective device inside the consumer unit is usually rated at 30 or 32 Amps - this may be either a fuse or a miniature circuit breaker. If a portable appliance is plugged into one of the socket outlets it can receive power at more than 30A before the protection operates. However, the maximum rating allowed on such appliances is only 13A.

If a small appliance, such as a radio, is plugged in it may only take 0.5A and so may only have a small cable between it and the socket - sometimes only 0.75 mm2 or 0.50 mm2 in cross-section. The problem then arises that if there is a short circuit or other fault in the appliance then a large fault current would flow through the cable. The cable may be unable to handle this current and a fire could start that could cause damage to property and injury or death to the people in the property. To prevent this a small fuse is put INSIDE the plug. This fuse is made in accordance with standard BS1362 and has a characteristic to operate quickly during a short circuit. The purpose of the fuse is to protect the cord between the appliance and the socket.

Part of the principle of the ring main system is that the earth circuit must be able to take a current that is guaranteed to blow the fuse in the plug if there is a sudden short circuit. The test requirement during production of 25A earth continuity is specified to ensure that this will happen. If the device does not have any conducting metal parts it may be classified as Class II and need not have an earth connection.

The fuses may be rated 3A, 5A, 10A or 13A. However they are not highly sensitive to overload current and in fact will not operate for half an hour even at 1.6 x the rated current. Their primary purpose is to protect against short circuit currents. The fuses are designed to give the minimum temperature rise when operating at their normal rating but still respond quickly upon the sudden occurrence of a short circuit.



The presence of the fuse inside the plug causes a problem! The fuse gets warm or hot in normal operation - the word 'fuse' means 'melt'. It must get hot - and this is normal. When the fuse gets hot so must the plug itself. The plug then gets even hotter because of the electrical connections inside the plug. For a non-rewireable plug the connections are usually crimped. The British Standard limits the maximum temperature rise in the plug to 52oC above ambient. The fuse has already taken up part of the permit temperature rise. That is why it is so important to make the best possible crimps and keep the temperature rise at these joints to a minimum.

If a non-rewireable plug is used on an appliance such as a radio taking less that 0.5A the plug itself will not get very hot. In this case it will never have to take 13A and so the heat generated in the connections (I2R) will be negligible.

However, if the plug is to supply a washing machine that may take up to 13A and has a motor that starts and stops the I2R loss will be much much greater.

A plug may have to supply an appliance such as a fan that has a motor - there is a current surge when it first starts but then the current settles down to a much lower level. In these cases it is allowed to have a fuse of higher rating than the cord supplying the fan.

If a non-rewireable plug is fitted to an appliance that will not normally take a large current it need not be tested for temperature rise at the full current of 13A with the I2R losses that his would give. In these cases the plug may be rated at less than 13A but it may have a fuse greater than the cord rating. The advantage to the manufacturer of doing this is that it is easier to achieve a successful Type Test against the standard BS 1363. However, for non-rewireable plugs the plug base must be marked with the rating of the fuse to be fitted - not the rating of the plug when it was Type Tested and as shown on the Licence. Common ratings for British '13A' plugs are 6A, 10A and 13A. The customer must decide what plug rating and what fuse rating he needs for his intended duty.

Plugs for use in Britain must be of a design approved by one of the nominated certification bodies such as ASTA BEAB Certification Services. The plugs are first 'Type Tested' in a laboratory. The production and test of the plugs in the factory must then be under regular surveillance by the certification body and must be subject to Annual Type Tests to confirm that no change in design or performance has been made. The plugs should not be 'CE' marked because they are in accordance with national rather than European regulations. In the UK these are called the 'Plugs and Sockets Regulations'. However, when they are used in conjunction with a connector the resulting 'cordset' should be 'CE' marked if it is to be sold separately (this marking may be on the packaging).

The Godfather

 

[Apache]

Good article.

customer must decide what plug rating and what fuse rating he needs for his intended duty.

:| (is it ok to 'scoob' the don?)

 

[The Godfather]

Good article. :|

(is it ok to 'scoob' the don?)

Thankyou Apache

The Don is pleased.

The Godfather

 

[SPECIAL LOCATION]

Page 2 of this tech sheet for MK logic plus...

http://www.farnell.com/datasheets/36688.pdf

left hand side

TECHNICAL SPECIFICATIONElectrical

Voltage rating:

250V a.c.

Current rating:

13A per socket outlet

(except 3 gang which is 13 amp in total)

therefore double gangs are 26A, otherwise no need for except statement re 3 gang? ?:|

This I would suggest concurs with Nicky's earlier post! {post#36}

(Although there are areas I agree to disagree with Mr T. on..

to tape or not to tape .. that is the question! ; \

26A for a double socket is what MK suggest for their Logic Plus range )

 

[batty]

Page 2 of this tech sheet for MK logic plus...http://www.farnell.com/datasheets/36688.pdf

left hand side

therefore double gangs are 26A, otherwise no need for except statement re 3 gang? ?:|

This I would suggest concurs with Nicky's earlier post! {post#36}

(Although there are areas I agree to disagree with Mr T. on..

to tape or not to tape .. that is the question! ; \

26A for a double socket is what MK suggest for their Logic Plus range )

They may say that but and possibly they could handle that load for a short time but I would not advise it. As said in an earlier post I read an article that suggested using 13 amp single sockets on temporary installations ie building sites so sockets where not overloaded. I have tried to find it but have not.

Batty

 

[SPECIAL LOCATION]

On the subject of heating I found the following article from the ASTA BEAB site, it may be worth noting that the fuse in the plug, will contribute significantly to the heating of the socket.Overview: The rules for British Plugs - Simplified

01/02/2006.........



The presence of the fuse inside the plug causes a problem! The fuse gets warm or hot in normal operation - the word 'fuse' means 'melt'. It must get hot - and this is normal. When the fuse gets hot so must the plug itself. The plug then gets even hotter because of the electrical connections inside the plug. For a non-rewireable plug the connections are usually crimped. The British Standard limits the maximum temperature rise in the plug to 52oC above ambient. The fuse has already taken up part of the permit temperature rise. That is why it is so important to make the best possible crimps and keep the temperature rise at these joints to a minimum.

I have a picture illustrating the results of the above problem...

{I like pictures }

http://i291.photobucket.com/albums/ll306/SPECIALLOCATION/CLOSEUPOFMELTING.jpg

This was a Tumble Drier plug!! :|

Note it is the Live, Fuse side pin that got hot!

As Apache says..

Very good article!Applaud SmileyApplaud Smiley

{bet you had your boys working hard to type all that out! :^O :^O}

 

[SPECIAL LOCATION]

They may say that but and possibly they could handle that load for a short time but I would not advise it. As said in an earlier post I read an article that suggested using 13 amp single sockets on temporary installations ie building sites so sockets where not overloaded. I have tried to find it but have not.Batty

Legally I doubt they could print it in a Tech Spec if it was not a load that could be sustained for a reasonable time!

As far as I can remember the internal metal track bars inside a socket are actually much greater in size that 2.5mm!

which would be the prime limiting factors IHMO?

 

[Apache]

Legally I doubt they could print it in a Tech Spec if it was not a load that could be sustained for a reasonable time!As far as I can remember the internal metal track bars inside a socket are actually much greater in size that 2.5mm!

which would be the prime limiting factors IHMO?

Is it not the plastic front going black and charred that is limiting?

 

[Mr Sworld]

As I've said nicky, I would reasonably expect a double 13A socket to supply more than 13A.

I would too but only for a short time. However I would also expect a single gang 13A socket to provide more than 13A for a short time. However the continuous load rating is still only 13A.

 

[The Godfather]

I have a picture illustrating the results of the above problem...{I like pictures }

http://i291.photobucket.com/albums/ll306/SPECIALLOCATION/CLOSEUPOFMELTING.jpg

This was a Tumble Drier plug!! :|

Note it is the Live, Fuse side pin that got hot!

As Apache says..

Very good article!Applaud SmileyApplaud Smiley

{bet you had your boys working hard to type all that out! :^O :^O}

But that can happen if the (physical) connection to the fuse is not sound Specs.

Don