63 amp socket Table 41.1

[Cookie]

Does anyone know why 0.4 seconds was extended to 63 amp socket circuits? Is this because supply sources are getting stronger?

 

[DPG]

I think they are trying to bring protection for 63A sockets in line with the requirements for socket outlets of lower current ratings. Same with the RCD requirements changing.

Unless there's another reason anyone else is aware of.

 

[Cookie]

Guess so, but I can't see the danger being more or less for a fixed 63 amp device vs one on a plug.

 

[Julie.]

Guess so, but I can't see the danger being more or less for a fixed 63 amp device vs one on a plug.

Danger is more for plugged devices due to the flex used.

Fixed loads are usually installed via flexi conduit, armoured cable or similar heavy duty cables.

Plugged in devices usually end up with fairly unprotected trailing leads.

 

[Rockingit]

In my world there's lots of things that are a final circuit (device) on a 63A ceeform, both 1ph and 3ph, so in that sense it makes, er, sense. But then that exact same cable can plug into and power a submain (rubber box distro's) and become a 5s circuit, so it's all about having a thought-through approach.

 

[Cookie]

Danger is more for plugged devices due to the flex used.

Fixed loads are usually installed via flexi conduit, armoured cable or similar heavy duty cables.

Plugged in devices usually end up with fairly unprotected trailing leads.

I guess that means added impedance increasing disconnection times?

 

[i=p/u]

Final circuit or dis circuit is the question.

 

[Julie.]

I guess that means added impedance increasing disconnection times?

No,

Likelihood of damage to cables.

Rcd are for the protection of persons, not equipment.

Trailing leads, associated generally with plugged in equipment tend to get damaged exposing cores, or potential short circuits.

An example may be a 63A welding set, loads of steel plate being moved around, and potential for dropping plate sharp edge-on to the welder supply cable.

Fixed equipment tends not to be like this.

 

[Julie.]

Final circuit or dis circuit is the question.

Socket outlet is a final circuit.

 

[Rockingit]

Socket outlet is a final circuit.

...except when it's plugged into a distribution board

 

[pc1966]

...except when it's plugged into a distribution board

Wow! "Have DB, will travel"

 

[Rockingit]

Pretty much!

 

[Cookie]

No,

Likelihood of damage to cables.

Rcd are for the protection of persons, not equipment.

Trailing leads, associated generally with plugged in equipment tend to get damaged exposing cores, or potential short circuits.

An example may be a 63A welding set, loads of steel plate being moved around, and potential for dropping plate sharp edge-on to the welder supply cable.

Fixed equipment tends not to be like this.

To me that would mandate RCDs instead of reduced disconnection, but what do I know? ?

 

[Julie.]

To me that would mandate RCDs instead of reduced disconnection, but what do I know? ?

See post 2

Both aspects are being brought in line.

 

[Cookie]

See post 2

Both aspects are being brought in line.

Alright.

So double checking that would mean a hard wired cooker could get away with 5 seconds, but a flex cooker would require 0.4 seconds? In the US almost all cookers have plugs on them.

 

[Julie.]

Alright.

So double checking that would mean a hard wired cooker could get away with 5 seconds, but a flex cooker would require 0.4 seconds? In the US almost all cookers have plugs on them.

Sort of, the cooker example is unlikely to fall within this range (unless industrial, or especially large), but yes there could be loads which are final circuits between 32A and 64A where being hard-wired or plugged in would make such a difference.

In the uk a plug may be used up to 13A on a cooker, above this it is almost always wired in except in a few occasions such as temporary catering where industrial type plugs will be used.

The biggest area to be impacted is industrial as they are likely to have portable/mobile loads that fall in this range.

Essentially as newer versions of the standard are developed the limit of 0.4s and the use of rcds is getting applied to more and more.

I think the whole idea is that eventually all final circuits supplied by a socket outlet should have rcd and 0.4s.

Remember this clause is aimed at final circuits only.

Distribution circuits do not fall under this clause - reflecting the need for discrimination, and the likelihood that when used for distribution it would be controlled by knowledgeable persons.

 

[Cookie]

My understanding is that in India, all final circuits are required to disconnect in 0.4 seconds or less. Personally I like the idea.

An exception for 5 seconds is needed for sub circuits though- 60 amp life safety feeder must selectively coordinate with the final OCPDs.

 

[Rockingit]

My understanding is that in India, all final circuits are required to disconnect in 0.4 seconds or less. Personally I like the idea.

An exception for 5 seconds is needed for sub circuits though- 60 amp life safety feeder must selectively coordinate with the final OCPDs.

India. An interesting place to work with electrics (as I have)...... least said about their 'standards' the better, I feel.

 

[pc1966]

India. An interesting place to work with electrics (as I have)...... least said about their 'standards' the better, I feel.

Not so much the standards, but any sort of compliance to them!

 

[Cookie]

India. An interesting place to work with electrics (as I have)...... least said about their 'standards' the better, I feel.

India has one of the most beautiful electrical systems on earth, minus all the DIY of course.

 

[pc1966]

To be fair I have worked with some really talented Indian engineers, but they are not the ones being paid peanuts by outsourcing companies or filling in for a boss who won't get a professional in to do the job properly.

 

[Rockingit]

India has one of the most beautiful electrical systems on earth, minus all the DIY of course.

I get the impression we may have differing experiences on this one. It was in India (Mumbai, to be exact [though other places and experiences also exist]) that in a 5* hotel I enquired why the earthing had been removed.... “because if we put it back on all the trips go”.

 

[Cookie]

I get the impression we may have differing experiences on this one. It was in India (Mumbai, to be exact [though other places and experiences also exist]) that in a 5* hotel I enquired why the earthing had been removed.... “because if we put it back on all the trips go”.

Sadly, not everyone follows the regs, standards or understands what they are doing.