Garden Socket installation

[Hysteresis]

No, the equipment should be internally protected. The manufacturer has no means of knowing whether a fused plug will be used.

No, the equipment should be internally protected. The manufacturer has no means of knowing whether a fused plug will be used.

The fuse in both cases is only required because the equipment being used is too small for the ring circuit protective device. Plus it limits the total load to 13A - likely sufficient from what you state but not always the case.

Use adequate cable and accessories and the fuse would not be required.

The fuse is not there to protect the equipment or the cables connected to power it. We are getting into fine definition here, but the fuse is there to protect anything downstream of the fuse from receiving power under fault conditions which will provide energy to enable or support combustion and as such endangering life from the spread of that combustion. It is also there to protect personal from electrocution under fault conditions in the case of an Earth fault.
Some equipment powered by electric power does not have any form of separate isolating protection under fault conditions, such as Luminaries and the sole means of protection is the Fuse.
Even other equipment has badly designed protection under fault condition, as an example the Clothes Drier fiasco which resulted in house fires a few years ago. The fuse is there for the protection of life which is endangered by the spread of combustion initiated by faulty equipment down stream of the fuse.
Clearly by removing the power to to the fault, a secondary effect is the protection of the Equipment and the cables but the primary requirement is the protection of Human Life by either electrocution or Fire.

 

[EFLImpudence]

The fuse is not there to protect the equipment or the cables connected to power it.

The fuse is to protect the cables; not the equipment. End of.

We are getting into fine definition here,

No, it is the basics.

but the fuse is there to protect anything downstream of the fuse

Only the cable; not the equipment(appliances)...and upstream if it is not fitted at the point of reduction in current carrying capacity of the cable.

from receiving power under fault conditions which will provide energy to enable or support combustion and as such endangering life from the spread of that combustion.

Not sure what receiving power means. Power might be drawn by a fault in the cable or a fault or overload in the appliance. The fuse will protect the cable from overheating leading to what you mention.

It is also there to protect personal from electrocution under fault conditions in the case of an Earth fault.

Yes, but the MCB would probably do that anyway.

Some equipment powered by electric power does not have any form of separate isolating protection under fault conditions,

Then it should have.

such as Luminaries and the sole means of protection is the Fuse.

The internal wiring should not cause such a fault.

Even other equipment has badly designed protection under fault condition,

Then it is not fit for purpose.

as an example the Clothes Drier fiasco which resulted in house fires a few years ago.

I don't know how they caught fire but they might overheat and it be nothing to do with the electrics.

The fuse is there for the protection of life which is endangered by the spread of combustion initiated by faulty equipment down stream of the fuse.

As above, it might be nothing to do with anything a fuse could protect against.

Clearly by removing the power to to the fault, a secondary effect is the protection of the Equipment and the cables but the primary requirement is the protection of Human Life by either electrocution or Fire.

In these circumstances then the product was not fit for purpose but the fixed wiring protection is not there to compensate for faulty products.

A 6mm² T&E has a CCC of 47A Method C, therefore it could have 45A MCB whether you connect to it a cooker or one lamp.

 

[Taylortwocities]

I would say that is rather obvious but not sure why you said it.

Because Winston has to say something.
Even thought the something (usually) does not add any value to the topic.

 

[securespark]

I have been disparaging of ring final circuits since around 1990.

Hate their design, hate the potential for faults and hate the testing regime.

Radials are so much simpler.

I would say the cable should be buried twice as deep.

14th Ed. Regs discouraged against cables being attached to fences. I would say attaching it to the concrete gravel boards would be OK

 

[winston1]

Even thought the something (usually) does not add any value to the topic.

Rubbish.

 

[Hysteresis]

EFLImpudence,
You are missing the whole point. The whole point of protection is Human Safety. If life is not threatened then what purpose would be served by saving the cable or any other hardware, apart from financial.
A lot Luminairs do not have any form of protection other than the fuse, just have a peep at any ceiling rose. A neighbours house was burned to the ground thankfully without loss of life, the investigation determined the cause was a Domestic Downlighter, the fuse/MCB/RCD did not operate quick enough to save the fire, the downlighter did not have any form of protection to prevent the fire. These down lighters are readily available and regularly installed today, and in your words are NOT SAFE/FIT FOR PURPOSE. Thankfully the GU10 halogen bulbs are being replaced with LED units with very little heat generation associated with them, all of these halogen bulbs or at least the non fire proof units should be replaced by law in my view.
The Clothes Driers to which I referred were marketed by Hotpoint (Probably manufactured in the Far East). I had one and fortunately the fault did not manifest itself in my machine but Hotpoint replaced it after 10 years service free of charge. The point being that in your words, it was not fit for purpose, but they were sold in there thousands. Incidentally the fire in these units WAS caused by the Electrics, without the electrics they would not spontaneously combust.
The whole point of protection is the safety of Human life, the cable and any electrical devices are replaceable, Human Life isn't. There is another point of protection already mentioned and that is the cost of the hardware replacement but that is another argument.

 

[EFLImpudence]

EFLImpudence,
You are missing the whole point.

Nope.

The whole point of protection is the safety of Human life, the cable and any electrical devices are replaceable, Human Life isn't.

Now who's missing the point?

Protecting the cables is not because we care about cables. It is the term used.

It is so that the power is disconnected before they overheat and cause danger to persons.


Metal consumer units are now required because the London Fire Brigade said too many were catching fire. It is certainly because of loose connections; not the material.
There is nothing any fuse nor MCB could do anything about.

 

[EFLImpudence]

A lot Luminairs do not have any form of protection other than the fuse, just have a peep at any ceiling rose.

What do you think there is in a ceiling rose? The fixed wiring.

A neighbours house was burned to the ground thankfully without loss of life, the investigation determined the cause was a Domestic Downlighter, the fuse/MCB/RCD did not operate quick enough to save the fire,

Maybe there was nothing electrically wrong that a fuse would be able to detect.

the downlighter did not have any form of protection to prevent the fire. These down lighters are readily available and regularly installed today, and in your words are NOT SAFE/FIT FOR PURPOSE.

I don't know if the lamp was at fault. It might have been covered with thermal insulation or been too close to something.

Thankfully the GU10 halogen bulbs are being replaced with LED units with very little heat generation associated with them,

Well - less; I wouldn't say very little.

all of these halogen bulbs or at least the non fire proof units should be replaced by law in my view.

There is no such thing as a fire-proof unit. Are you confusing fire-rated?

 

[bernardgreen]

No, fuses are not to protect the equipment - just the cables.

The fuse can also reduce the risk of a fire developing inside the equipment when the equipment becomes faulty and starts to overheat.

If the fault results in the equipment drawing more current then the fuse will limit the amount of heat that can be produced in the faulty equipment.

Fitting a fuse in the plug for every item of equipment will not ( can not ) prevent every possible fire but if it prevents a few fires then the fitting of a suitable size fuse is a sensible policy

 

[bernardgreen]

There is no such thing as a fire-proof unit.

There are, they are called Intrinsically Safe.

(edit) Their construction ensures they cannot become hot enough to ignite material or gas in their vicinity.

https://www.omega.co.uk/technical-learning/understanding-what-is-meant-by-intrinsically-safe.html

They are unfortunately far too expensive for use in a normal domestic installation.

 

[RandomGrinch]

The fuse can also reduce the risk of a fire developing inside the equipment when the equipment becomes faulty and starts to overheat.

If the fault results in the equipment drawing more current then the fuse will limit the amount of heat that can be produced in the faulty equipment.

Fitting a fuse in the plug for every item of equipment will not ( can not ) prevent every possible fire but if it prevents a few fires then the fitting of a suitable size fuse is a sensible policy

When PAT testing, you wouldn't believe the amount of IEC leads that are rated at 5A, but are fused for 13A and are supplying a device of around 2kW!
Rarely any IEC leads have a connector rated over 10A apart from actual kettle leads!

 

[bernardgreen]

you wouldn't believe the amount of IEC leads that are rated at 5A, but are fused for 13A

Plugs sold loose ( no cable ) should be sold fitted with a THREE amp fuse or without any fuse. The customer then buys a fuse suitable for the combination of lead and appliance.

 

[RandomGrinch]

Plugs sold loose ( no cable ) should be sold fitted with a THREE amp fuse or without any fuse. The customer then buys a fuse suitable for the combination of lead and appliance.

Yes, and this might cut to the crux of the matter (and might contradict my original post!)
Unfortunately most 'customers' aren't educated to look for appliance power ratings, IEC lead ratings and be able to pick an appropriate fuse value, especially with the usual domestic values of 3, 5 and 13A.
I might be able to wire a garden circuit in SWA, connect it appropriately to a 13A socket, but it doesn't mean the next occupier of my house will know how to make sure it is still safe. They will just plug it in and turn it on!
Maybe there is a reason for sticking to the regs

 

[BS3036]

Because Winston has to say something.

In this case he seems to be comparing a book of regulations with statues, which seems to be so weird a concept as to make me wonder if he isn't losing it. Or lost it a long time ago. Oh well, if it gives him pleasure...

 

[winston1]

When PA testing, you wouldn't believe the amount of IEC leads that are rated at 5A, but are fused for 13A and are supplying a device of around 2kW!
Rarely any IEC leads have a connector rated over 10A apart from actual kettle leads!

Outside the UK those same leads have plugs without fuses and are only protected by 16 amp MCBs. Are those leads really only rated at 5 amps? If so the cable will be smaller than the minimum allowed