Aerial Power Supply from Lighting

[bernardgreen]

All the sockets in my bungalow are fed from the loft. Having solid floors makes it the best way of doing it.

A clue at last into the reasoning (?) behind Winston1's obsession insistence that put a 13 Amp socket on a lighting circuit is bad practice.

He has power circuits in his loft. he doesn't have to use the lighting circuit when a 13 Amp socket is required in his loft.

 

[SUNRAY]

All the sockets in my bungalow are fed from the loft. Having solid floors makes it the best way of doing it.

At least you won't fall down the stairwell when you come through the ceiling.

 

[winston1]

A clue at last into the reasoning (?) behind Winston1's obsession insistence that put a 13 Amp socket on a lighting circuit is bad practice.

He has power circuits in his loft. he doesn't have to use the lighting circuit when a 13 Amp socket is required in his loft.

Nothing to do with it at all. When I rewired my previous 2 residences I included a spur to the loft in each case. It just seemed to be the sensible thing to do even though I had no immediate use for them.

 

[SUNRAY]

Nothing to do with it at all. When I rewired my previous 2 residences I included a spur to the loft in each case. It just seemed to be the sensible thing to do even though I had no immediate use for them.

I have a chalet style property with 4 'loft spaces' adjacent to the bedrooms where all the power circuits run, I have 13A sockets in 2 of those spaces where it would have been just as easy to use the power or lighting circuits. I specifically chose the lighting circuits on the basis I'd prefer to have unfused plug top PSUs protected by 6A OCPD's rather than 32A. A 3rd space has sockets on the ring circuit but that is more like a cupboard and powered items in there all have plugs with appropriate fuses including Henrietta who lives in there permanently plugged in.

 

[winston1]

I'd prefer to have unfused plug top PSUs protected by 6A OCPD's rather than 32A.

They may be unfused but they are not unprotected internally. They are approved for use in the UK after all.

 

[SUNRAY]

They may be unfused but they are not unprotected internally. They are approved for use in the UK after all.

It seems you have never seen the mess that's frequently created when they fail, I imagine you'll change you statement when that happens to you.

 

[bernardgreen]

They may be unfused but they are not unprotected internally.

STOP giving out dangerous inaccurate information, Many are unprotected internally.

They are approved for use in the UK after all.

That is applicable only if the user has purchased the item from a reputable supplier and not from a dubious on-line supplier.

I am aware of a reputable UK company who discovered the hard way that the off shore company supplying them with power supplies had changed the design without the UK company's permission. The first the UK company were aware of the changes was when a unit caught fire. They examined other items from the same batch and discovered the changes.

 

[winston1]

STOP giving out dangerous inaccurate information, Many are unprotected internally.

Source? But if that is the case I doubt whether a 6a or 32a MCB would make much difference.

 

[winston1]

That is applicable only if the user has purchased the item from a reputable supplier and not from a dubious on-line supplier.

I assume Sunray as an electrician would only get them from a reputable supplier.

 

[bernardgreen]

I assume Sunray as an electrician would only get them from a reputable supplier.

But the average person is not an electrician.

But if that is the case I doubt whether a 6a or 32a MCB would make much difference.

Probably not, but it is very difficult to consider every possible failure mode.

For example a faulty module might carry 6 Amps ( dissipating 1.5 kW ) for some time, maybe long enough to set something else on fire while the same module could be blown apart by a 32 Amp fault current before it had time to ignite other items.

( yes that is an observation that supports Winston1's opinion about 13 Amp sockets on 6 Amp lighting circuits )

 

[SUNRAY]

I assume Sunray as an electrician would only get them from a reputable supplier.

What do you call a reputable supplier?

The plug top supply with my Sky router? (overheated) Or the one supplied with a colleagues new Dewalt? (big bang and horrible accrid dark cloud).


My son in law was a fireman and can tell of many cases of such supplies starting fires.

Most of those I've opened after failure show signs of overheating but finding any sort of fuse; be it a physical fuse or part of the pcb track etc is virtually non existant.

I learnt a lot of years ago to avoid plugging unfused devices into high power circuits whenever practical. In my portable kit (miles of cable and many 4ways) I have 4ways dedicated for chargers with 3A or 1A fuses and heavily labled.

 

[Harry Bloomfield]

Most of those I've opened after failure show signs of overheating but finding any sort of fuse; be it a physical fuse or part of the pcb track etc is virtually non existant.

There are other way of limiting current draw, than fuses and narrowed PCB tracks. If current draw is very limited I tend to add a suitable value of resistor in the supply, so even if a a dead short occurs downwind of the resistor, the resistor will not over heat. It's a common technique in wall wart power supplies.

 

[SUNRAY]

There are other way of limiting current draw, than fuses and narrowed PCB tracks. If current draw is very limited I tend to add a suitable value of resistor in the supply, so even if a a dead short occurs downwind of the resistor, the resistor will not over heat. It's a common technique in wall wart power supplies.

It's even more common that all of those protection and filter components don't exist IME

 

[bernardgreen]

I tend to add a suitable value of resistor in the supply, so even if a a dead short occurs downwind of the resistor, the resistor will not over heat.

How does that work in wall wart supply ?

When 230 volts is applied to a 10,000 Ohm resistor the heat produced will be about 5 watts ( W = V²/R )