Electrical Problem, melted charger!!!?

[winston1]

Sorry - did not make clear the kettle is on a different plug.

I'm sure it is. No one could easily wire a kettle and tumble dryer into the same plug. The point is they are probably on the same circuit.

I repeat tumble dryers should not be on a four way. Although technically rated at 13 amps they are not generally suitable for this sort of load.

 

[dishman]

Lol - terminology mix up again.....I ment the kettle and the dryer are not indevidually plugged into the same 4 way. They are on opposite sides of the kitchen plugged into different sockets.

I do take your point then it is not ideal for a tumble dryer to be plugged into a 4 way....a bit restricted at the moment though

 

[dhutch]

While not ideal, if there is very little else on it (and a small lcd tv is not huge) worse things have happened, although some of the cheaper 4 ways for sale in supermarkets and the like do not inspire confidence.

If your adding in an Oven, I could see you taking a ring main.

Kettle 3kW, tumble dryer 3kW, Oven 3kW = circa 9Kw, approx 40 amps.

My house is on a single ring, including a 2.6kW electric over and a 3kW kettle, but fortunately the conservatory is on its own circuit (a lollipop using an old shower supply in fact) with the washer and dryer in it.


Daniel

 

[ericmark]

First point I Googled the part number you gave D41-12-250 and I get 110 volt units. I hope that is an error and you did not use a 110 volt device?

It shows a unit with a lead and coaxial plug in the main these are power supplies rather than chargers however I have used a power supply like that to power a charger for AA batteries and also charge batteries inside phones etc.

The new NiMh batteries do require better quality chargers to old NiCad batteries and it is easy to use wrong type. The NiMh batteries have been given world wide news coverage with laptops bursting into flames and air craft fires. Although we call them NiMh it would seem there are many ways to build these batteries so they are not all the same.

To charge a battery there are three basic ways. One very low charge rate typically 16 hours so over charging does no damage. Two temperature control it uses the fact electrical energy to chemical energy no heat so while battery is charging they are cool but one charged all electrical energy goes to heat which is used to turn off charger. Third uses delta V technology that follows the volt curve of the battery works well with single cells but with a battery of cells it can be foxed and result in over charging.

The cheaper power supplies are a simple transformer they do fail but could well last 10s of years. The more expensive type use a switched mode system and have electrolytic capacitors these have a limited life so as a result so does the charger although while working they are better.

In spite of what others have said about extension leads they are good for small chargers as they allow them to rest on the flat surface rather than hang off a wall and also because it insures it's protected by a fuse in the plug of the extension lead. In theroy charger should have built in fuse but china does not seem to worry about safety the way we do and UK is odd one out with sockets with the ring final so EU socket on 16A protective device UK on a 32A device. Many chargers sold with adaptors to work in UK the adaptor should be fused but often they are not.

For a RCD to trip from time to time is normal but with a MCB it is rare in out houses we can have the RCB and MCB combined called a RCBO and these will trip from time to time like the RCD.

We can split our electrical stuff in to four rough groups.
Super high power like shower never use plug and socket.
Low power under 2kW
High power short duration like kettle.
High power long duration like immersion heater.

The last group should not be plugged into a ring final it should have it's own dedicated supply in same way as super high power but there are some items which have been traditionally supplied with a 13A plug and plugged into our ring final. The big one is the tumble drier this should not be plugged into ring final but we often do.

The oven (under 3kW), Washing machine, and dish washer should also have a dedicated circuit but in real terms all these units switch on and off and don't draw full current for long. So although they are classed as fixed (due to weight even if not build in) and so being over 2kW should have a dedicated supply in real terms they are not so much of a problem.

Until 2004 most kitchen electrics were altered by semi-skilled (being kind) kitchen fitters and left a lot to be desired. From 2004 until last year electricians installed most kitchen electrics and they should have been able to read the regulations and installed dedicated supplies although often these were in the form of dedicated kitchen rather than for each item.

When my mothers kitchen was done a large SWA cable was run around the outside of the house to supply it rather than go through the house. There are ways around the problem it's identifying the best method.

But first is to identify what you already have. The MCB will normally have a letter then number there are some old ones without the letter marked class 1 to 4 but rare. So B, C, or D and number likely 32 so will be a B32. This means surge of 160A and running 32A the B refers to surge being 5 times more than run amps. Where combined with a RCD it will also have something like 30ma marked on it and a test button.

Today nearly all buried wires and 13A sockets need RCD protection but it's not retrospective so OK when fitted before 2008 however it does present a problem when extending existing circuits. It means we can add fused spurs using a RCD FCU but not extend the ring and comply with RCD regulations. There is always a way around the problem but not as straight forward as before.

I don't know that Wylex number and there have been many Wylex boxes years ago the fuse box had interchangeable bases and these could be swapped for MCB so many early boxes still in service have no way for a RCD to be included. Even when we went to MCB boxes often there is not enough length to fit RCBO in the box but with latter ones is a relatively easy swap. Picture of box will help.

To be honest with the old 4 way Wylex fuse box with a single ring for all of the house people can still get away with all the modern labour saving stuff without the fuse blowing or the trip tripping basic fact we rarely use it all together. So it would seem something has been missed hence long post so you can consider what you have.

 

[ekmdgrf]

The new NiMh batteries do require better quality chargers to old NiCad batteries and it is easy to use wrong type. The NiMh batteries have been given world wide news coverage with laptops bursting into flames and air craft fires. Although we call them NiMh it would seem there are many ways to build these batteries so they are not all the same.

The batteries that spontaneously burst into flames are Lithium-Ion rather than NiMH. A quick look at the Periodic Table should readily indicate why you wouldn't want it on your aircraft

 

[winston1]

[quote="]

The big one is the tumble drier this should not be plugged into ring final but we often do.

The oven (under 3kW), Washing machine, and dish washer should also have a dedicated circuit but in real terms all these units switch on and off and don't draw full current for long. So although they are classed as fixed (due to weight even if not build in) and so being over 2kW should have a dedicated supply in real terms they are not so much of a problem.[/quote]

So where do I find this regulation which says appliances over 2kW should have a dedicated circuit and not plugged into a ring final? Perhaps you should tell the manufacturers of these appliances as well and ask them why they sell them with BS 1362 plugs fitted.

 

[JohnW2]

So where do I find this regulation which says appliances over 2kW should have a dedicated circuit and not plugged into a ring final?

It's not 'a regulation'. It is 'guidance' in ('informative') Appendix 15 of BS7671, as one of the suggested measures to avoid overloading of a ring final circuit.

Kind Regards, John

 

[dhutch]

I must say, I have yet to come across a house that had dedicated feeds to the; oven, kettle, and dishwasher, or for that matter; washing machine, tumble dryer.

Normally the five of them are not on the same ring, but dedicated feeds for anything other than power showers (more like 6 or 9kW) and cookers, is near on unheard of in my experience of domestic applications.


Daniel

 

[ekmdgrf]

I must say, I have yet to come across a house that had dedicated feeds to the; oven, kettle, and dishwasher, or for that matter; washing machine, tumble dryer.

Normally the five of them are not on the same ring, but dedicated feeds for anything other than power showers (more like 6 or 9kW) and cookers, is near on unheard of in my experience of domestic applications.

Daniel

You've obviously never been to my house OK, the kettle is on the socket ring but the oven, dishwasher, tumble dryer, washing machine, fridge, freezer, under floor heating and central heating all have their own circuits. Worthy of particular mention was the previous owners attempts to put the downstairs lights and bathroom fans on separate circuits.

 

[JohnW2]

I must say, I have yet to come across a house that had dedicated feeds to the; oven, kettle, and dishwasher, or for that matter; washing machine, tumble dryer.

To be fair, even Appendix 15 does not suggest most of that. As some of the measures suggested to avoid overloading of the cable, it suggests that the following should not be connected to a ring final circuit:

(ii)...immersion heaters, comprehensive electric space heating or loads of a similar profile.
(iii)...cookers, ovens and hobs with a rating exceeding 2kW

... so, of your list, ovens are the only items which Appendix 15 suggests should not be connected to a ring final. Nor,interestingly, does it say that the things it mentions should necessarily have dedicated circuits. It merely suggests that they should not be connected to ring final circuits - connecting them to radial finals (for which rating of OPD does not exceed the CCC of cable) would presumably be regarded by 'them' as OK.

Kind Regards, John

 

[dhutch]

Makes more sense. Thanks for the information.

 

[JohnW2]

Makes more sense. Thanks for the information.

You're welcome. As you say, it essentially makes sense - and don't forget it's only ('informative') 'guidance', not 'regulation'.

Kind Regards, John