Sockets in my house MELTING my plugs!

sincere113

Yes you are correct in your post.

And I did make a mistake earlier in omitting the cos phi from the power calculation. Oops....:o

2011

sincere113 wrote: »

Yes you are correct in your post.

And I did make a mistake earlier in omitting the cos phi from the power calculation. Oops....:o

Fair play, thanks:)

Bruthal

sincere113 wrote: »

And I did make a mistake earlier in omitting the cos phi from the power calculation. Oops....:o

Well just pretend you were calculating the power for the immersion element, you wont really need it then:)

Bruthal

2011 wrote: »

There are some obscure (for a domestic installation) contradictions to this such as switched mode power supplies but they are generally units that do not consume very much power in the first place and therefore would not be lightly to be drawing a current high enough to melt a socket.

The switch mode regulators dont really increase current as the supply voltage reduces though. They just vary the on to off ratio in the high speed switching mode. This will show as a higher current reading on an ameter, but the reality is, its a fixed current (for the connected load)having its pulse width varied

So if the supply voltage reduces, the on pulse width increases, so the same current is just on for a higher percentage of the pulse width, to maintain the output voltage at a stable level for the given load connected.

Bruthal

sincere113 wrote: »

In a round about way I think that we agree and it boils down to the interpretation of Wildefalcons post. Here's why.

Wildefalcon states that "If the voltage drops, and the wattage remains the same, then the current (amps) increases."

I just have to ask this, do you honestly think that wildefalcon was thinking along the lines of appliances having power regulators in them, when he mentioned the above? I really dont.

I do think he was assuming a 2kw kettle would still be working as a 2kw kettle, even if the voltage reduces. And this is why he mentions...

and the wattage remains the same

After all, its rating plate will still say its 2kw. And it still would in fact be a 2kw kettle, as its assumed it will be used in and around its rated voltage.

Maybe he can tell us himself.

2011

robbie7730 wrote: »

So if the supply voltage reduces, the on pulse width increases, so the same current is just on for a higher percentage of the pulse width, to maintain the output voltage at a stable level for the given load connected.

Correct.
The reason the duty cycle increases is to maint constant power output.
The effect is a higher average input current.

sincere113

If Wildefalcon meant that if he plugs in a 2KW kettle then you always get 2KW out of it regardless of input voltage then he is wrong;

If on the other hand he meant that if you reduce input voltage and manintain the power consumed then the current increase. This is correct.

At the time of his post he didn't refer to any appliance or power rating but made a broad statement.

Some domestic products like the ones I mentioned can handle some juicy currents through their switching devices though.

Bruthal

sincere113 wrote: »

If Wildefalcon meant that if he plugs in a 2KW kettle then you always get 2KW out of it regardless of input voltage then he is wrong;

If on the other hand he meant that if you reduce input voltage and manintain the power consumed then the current increase. This is correct.

At the time of his post he didn't refer to any appliance or power rating but made a broad statement.

Yes, but you still seen it as correct beyond all else.

Some domestic products like the ones I mentioned can handle some juicy currents through their switching devices though.

The thing is, you just came in saying this person is correct, this other person is wrong etc, based soley on the idea that appliances can have micro controllers in them, as if this is the norm. There was no view taken by you of any other possibilites really(until late on in the thread), including the fact that its likely that anyone talking about the power output of an appliance is not going to be talking about triac switched/micro controller based appliances.

I mean, you post in #32 how to get a higher current with the same wattage, but a lower voltage. And this is after my post #30 which you dismissed as incorrect.

All this based on the fact a micro controller can pwm an appliance, instead of basing it on the realities of the actual appliances in general use, including the Op`s vacuum cleaner, the highest current which it can pull being if it was jammed stopped, which is the exact same as its starting current, and even this in a vacuum cleaner wont burn a socket.

If someone askes what wattage 10 lamps will take, i wont say 1kw is incorrect(10 x 100w bulbs), simply because 30 watts can be the wattage for 10 led lamps. That would be misleading.

Bruthal

2011 wrote: »

The impedance is irrelevant as it is the resistive component of impedance that causes the heating effect i.e. heat generated = (I^2)R and not (I^2)Z

That is true of the appliance`s own heat produced alright.

However, the impedence of the appliance does have relevance on the OP situation, as the higher the impedence, the lower the current flowing into the appliance. This will reduce the current (compared to DC resistive), and so reduce the possible heating of bad sockets.

(No doubt i will have slipped up again):)

That is why domestic installations are charged for kW hours and not kVA hours.

I think this is more to do with logistics really. There is no reason for not charging for KVA, other than the previously larger metering arrangements, and domestic installations are probably very close to parity for the vast majority of units used.

The KVArh amps still have to be generated, they are not free to generate just because they perform no work at the load. Like a 5kva generator. At a load of pf =1, the generator will power a 5kw load, but pf = 0.8, and this will be a 4kw load with the generator at max capacity.

sincere113

Robbie, through numerous posts and post from 2011 you have been proven wrong. I guess it took a little time for you to cop on to some of what I was saying as being true but swallow your medicine like a good chap and move on. You had no idea what I was talking about and by your recent comments you still haven't got it.

You are incapable of reading something and digesting and saying hang on he's got a point. I have commented on numerous times and quoted your correct comments. At not point have you done the same because of your stubbornness.

You would argue with yourself if left long enough. I have had a respectful and interesting exchange with 2011 which I thank him for, but you are a different kettle of fish my friend....

I work with electrical contractors on a daily basis and you strike me as being one of the ones close to retirement who's attitude is "look it works like this and has done since god was a little fella so no fecker will tell me otherwise... Blinkers on!!!"

Bruthal

2011 wrote: »

Correct.
The reason the duty cycle increases is to maint constant power output.
The effect is a higher average input current.

Yes, but my point is, that its not really an obscure contradiction. The meter reading may be contrary to whats usualy observed alright.

but the max continous current wont be higher than the actual current pulses. Just more of them for the higher time based average current.

I actually made one for the fan in the car recently. The resistor plate thing corroded, so i made a PWM controller for it. Variable speed now.

2011

robbie7730 wrote: »

but the max continous current wont be higher than the actual current pulses. Just more of them for the higher time based average current.

Agreed.
The average can be greater even when peak value is less.

But lets face it AC voltage is normally expressed as an RMS value, which is it's DC equivalent voltage.

As you know the average of a Sin wave = 0 (the positive 1/2 cycle cancels out the negative). This is why we talk about RMS voltages with AC.

In Ireland we have 230V RMS in domestic installations, but the peak value is 230/0.707 = 325V

But we never talk about the peak value as it is pretty irrelevant. It is the same with PWM. The average voltage and current output is what counts as the power output will be directly proportional to this.

Bruthal

No doubt you will be getting a thanks from your new friend:D

2011

robbie7730 wrote: »

No doubt you will be getting a thanks from your new friend:D

Feck, I hope so after all this

Bruthal

2011 wrote: »

Feck, I hope so after all this

Im just glad you have proven me wrong in this thread:)

2011

robbie7730 wrote: »

Im just glad you have proven me wrong in this thread:)

Can I have that written in triplicate in your own blood please ???? :D

I have had to own up to few on this forum myself as I am sure you recall.

Bruthal

sincere113 wrote: »

Robbie, through numerous posts and post from 2011 you have been proven wrong. I guess it took a little time for you to cop on to some of what I was saying as being true but swallow your medicine like a good chap and move on. You had no idea what I was talking about and by your recent comments you still haven't got it.

You are incapable of reading something and digesting and saying hang on he's got a point. I have commented on numerous times and quoted your correct comments. At not point have you done the same because of your stubbornness.

You would argue with yourself if left long enough. I have had a respectful and interesting exchange with 2011 which I thank him for, but you are a different kettle of fish my friend....

I work with electrical contractors on a daily basis and you strike me as being one of the ones close to retirement who's attitude is "look it works like this and has done since god was a little fella so no fecker will tell me otherwise... Blinkers on!!!"

Well 2011 has pointed out quite a few mistakes i made, including one this morning in electronics, as has m cebee, meercat, castiron and a few others. I never have a problem with it. Why would i? But one thing is for sure, none of them start with this "near retirement age" or "my friend" derogotory stuff.

If you were looking for me to say you were right about household apppliances having micro processors in them, then yes, you were right.

As for having no idea what you were talking about, i have actually made my own PWM devices for control of RC servos (example), amongst other things, and program the pic chips, although in the example linked, i used 555 timer chips to generate the pulses. The thread is 5 pages and has a record of some of the technical stuff if your interested, or have any opinions as to improved methods.

These days i etch the PCBs etc. Not knowing they are using them in the power control of domestic appliances hardly means someone is not familiar with the principles. But the topic of this thread was never about micro controlled appliances, or whether they existed or not.

But anyway, try not to start this derogatory type stuff, and do engage in the discussion as if i was a nice lad, even though im not really:D.

Myself and 2011 have often clashed on some topics. It never becomes derogatory, nor do we start to make personal references as to the probable cause for the others opinon. (bloody ages since i was right:pac:(in the head i hear you say))

So relax there sincere, and maybe you can look past the "rights and wrongs" and we will have more meaningful discussions. But if you have no respect for my opinons because they differed from yours, thats fine too. I have no problem with that. I actually thought this was an interesting thread.

Bruthal

A change of heart today is it sincere:pac:

sincere113

What do you mean?? If you're refering to a removed post then I'm only following suit. And whats with the :pac: for? I don't know what you're trying to achieve, but you're making yourself look even more foolish.......

cast_iron

robbie7730 wrote: »

But anyway, try not to start this derogatory type stuff, and do engage in the discussion as if i was a nice lad, even though im not really:D.

Myself and 2011 have often clashed on some topics. It never becomes derogatory, nor do we start to make personal references as to the probable cause for the others opinon. (bloody ages since i was right:pac:(in the head i hear you say))

Well I was going to say nothing as I'm not one to stir, but since you have....in fairness you showed some of those sentiments yourself, accusing sincere of just reading a book to get his terminology and learning all from google. And you directed him off to some electrical knowledge page like he knew nothing.

Bruthal

cast_iron wrote: »

Well I was going to say nothing as I'm not one to stir, but since you have....in fairness you showed some of those sentiments yourself, accusing sincere of just reading a book to get his terminology and learning all from google. And you directed him off to some electrical knowledge page like he knew nothing.

It seemed a link was needed, as the poster said my opinion was incorrect that z = r in a resistive AC circuit, even though that would seem to be an electrical fact. So whats wrong with providing a link?

It would be nice if we could be given one ourselves, showing these machines, instead of a typed list of 5 machines, and a later claim to know for a fact 3 of them can be got.

I did not ask for a list to disprove they exist, as suggested by the poster, but to see them. Id have an interest in seeing them.


This has become about a vested interest by this poster. Common sense tells us that the principles mentioned in this thread are sound, not based on my opinions, but because they are electrical laws. These should be based on actual real life actualities, the vacuum cleaner in the OP`s case, not on a posters insistance that our fundamentals are wrong because regulated power appliances could possibly be aquired.

Its fair to say, they could well become common place. But until then, its possibly better to assess situations based on up to date experiences, even if they are the same "since god was a little fella".

If he wants to come back telling me to take my medicine, or that i must be near retirement age, or am a fool, then so be it cast iron. But im surprised at the misleading stuff that has went on in this thread, and the only interest from yourself seems to be about who said what to who.

cast_iron

robbie7730 wrote: »

If he wants to come back telling me to take my medicine, or that i must be near retirement age, or am a fool, then so be it cast iron. But im surprised at the misleading stuff that has went on in this thread, and the only interest from yourself seems to be about who said what to who.

I found the thread an interesting read, actually. I made my point early that sincere's argument was entirely out of context in this thread. I had no interest in arguing against either of ye further down as funnily enough, to me it seemed ye were both effectively right but on about different things. And neither willing to give in

And no, I don't approve of his remarks insinuating you're a fool, old or in need of medicine. Talk like that doesn't do anyone's argument any good, and only lessens the credibility of he who comes out with it.

sincere113

When I said swallow your medicine I meant accept being wrong, I wasn't refering to Robbie needing medicine for any condition although my intentions were obviously misinterpreted.

In terms of the examples I gave you 5, I can't provide a link to a page an electrcial wholesaler whos product description goes into the workings of its control!! However Robbie read up on Intelligent motor controls or IMC's. Here you will find modern techniques to control motors using the methods I explained...Most modern electrical products use these techniques and so are found in the home. Robbie do you believe what I'm writing here? I don't think so. Since this thread has gone on for far too long and you don't seem to be getting it I'm not posting here again. It takes time for me to contribute to these posts and right now you are proving that its just not worth it. You posted again yesterday just to provoke me into writing again, for that I question your motives in you contributing on boards. I've proved you wrong Robbie. Just accept it.

I've read some of your other posts and most of what you write is questionable. Other posters have proved you wrong before and so anyone reading your contributions must take it with a pinch of salt.

Also please stop the juvenille PM you're sending me.

Bruthal

sincere113 wrote: »

When I said swallow your medicine I meant accept being wrong, I wasn't refering to Robbie needing medicine for any condition although my intentions were obviously misinterpreted.

In terms of the examples I gave you 5, I can't provide a link to a page an electrcial wholesaler whos product description goes into the workings of its control!! However Robbie read up on Intelligent motor controls or IMC's. Here you will find modern techniques to control motors using the methods I explained...Most modern electrical products use these techniques and so are found in the home. Robbie do you believe what I'm writing here? I don't think so.

Ok.....
I ready said Yes to this. Of course i believe you. Ironic you mentioned blinkers on, a post or 2 ago. A good few posts back i already mentioned laptop power supplies using switching regulation. Its common enough knowlege about them. So im still not sure what it is you still think your trying to prove. Is it this that im wrong about, because i genuinely do not know. Thats being honest.

I was intending sending you more PM`s with regard to info on these apppliances, as im genuinely interested. But since you find PM`s juvenile, and feel the need to tell everyone, thats pointless now.

Since this thread has gone on for far too long and you don't seem to be getting it I'm not posting here again. It takes time for me to contribute to these posts and right now you are proving that its just not worth it. You posted again yesterday just to provoke me into writing again, for that I question your motives in you contributing on boards. I've proved you wrong Robbie. Just accept it.

Yes. They are all wrong to base their opinions on electrical laws. Your right.

2011 wrote: »

Can't argue there, but in this case I agree with Robbie 100%

If a 230V 50W GU10 lamp has 110V applied to it it will no longer consume 50W.

2011 wrote: »

I dont agree. What he stated suggests that the current will increase if the voltage decreases so that the power consumption will remain the same as though this was the norm, he made no mention of voltage sensing:

2011
I take the rating to be what is written on the data sheet or the nameplate of the unit.

M cebee wrote: »

the power drops when voltage drops

rating of appliances is for a nominal voltage ie:230

sincere113
I've read some of your other posts and most of what you write is questionable. Other posters have proved you wrong before and so anyone reading your contributions must take it with a pinch of salt.

Of course they have, and so i have no problem with that, its an experience your not familiar with by the sound of it.
A first year apprentice has made far less electrical mistakes than the master electrician.

Also please stop the PM you're sending me.

Well the medicine must be working, i was nearing retirement age the other day, now im juvenile;)

Again its unfortunate you feel the need to post about the PM thing. Its just another indication of your manner. I think you should put it up, and lets see how juvenile it was. Nowhere near as juvenile as mentioning it i would suggest.

I always thought the electrical forum was very good, and i am far from the best poster on it, by a long way. There are quite a few good ones. But you have pushed forward a single agenda, completely out of context with this thread. So much so, that i sill dont fully know the actual point your putting forward. I dont know why you cant clearly state what this point is. Is it the existance of micro controlled appliances? And you think im saying they dont exist? Or is it my (and others) statements of electrical laws?

I already said i know micro controllers are in many items. I said i have made circuits myself, and programmed the chips with my own code. I have not however, seen a washing machine which has its entire power supply regulated. That does not mean that i think they dont exist, or will never exist.

So exactly what is it your going on about??? I think your entire theme in this thread was dreadful. Because you challenge established electrical laws and principles, and a few posters who posted them, as if these fully regulated demestic appliances were the norm in houses today.

You can keep saying "i proved you wrong", which has become your catch phrase now, it seems to be your new agenda.

That does not matter to me. What does matter though, is your mis-information here, confusing would be apprentices or anyone else that may find the thread informative, by saying electrical laws are incorrect because of these appliances.


............PS... Its hard to stop sending a single PM:pac:.............

Bruthal

.

Solair

I just want to step this back a few paces...

Is any other high power appliance causing your sockets to overheat?
E.g. heaters, kettles, etc?

If not, I would strongly suspect that the problem is the vacuum cleaner's plug.
Even if it's a moulded-on plug, it's quite possible that it has a bad connection inside.

As a first step, if the plug is rewirable, open it and see if there are any loose connections or burnt connections inside.

If it is, you need to cut the flex about 1" below the plug and fit a new one. Check that there is now burnt flex. If there is, you may have to cut more of it or have the flex replaced.

If it's a moulded plug, cut it off about 1" below the plug and fit a good quality PLASTIC (not the hard brittle old-fashioned type as these will almost certainly crack with normal use of a vacuum cleaner) plug. E.g. a "tough plug". These are identified by the standard number BS1363/A (BS1363 is just the normal version).

If other appliances are causing the same issue, you definitely need to get an electrician in and probably look at your options for going after the builder / original contractor for damages as the sockets, if they're that bad, could not possibly conform to IS411 or BS1363, which is a legal requirement. If they don't comply, they should not be on the market - no discussion about it at all!
There are a lot of cheap and nasty knock-offs that do not comply with standards. If something seems too cheap, it probably isn't the real deal.

Check the sockets for BS1363 labelling and the manufacturer's name. It should be on the back. Together with the stamp of the standards agency that signed off on it. Typically this will be BSI (kite mark), NEMKO (N in a circle), NSAI (Irish standards logo), ASTA (Diamond shape) etc etc. IS411 is the Irish equivalent standard, it's just a photocopy of BS1363. IS401 = Plug IS411 = Socket. It's relatively rare to see it printed on anything as the British Standards BS1363 codes are acceptable here as they are 100% identical.

If it does not have these, you should definitely contact the National Consumer Agency as it's a criminal offence to sell, stock or install anything that doesn't comply with these. There's actual legislation about it. For consumer protection and fire-safety reasons it's important that they're alerted so that someone can track the source down and issue a recall notice.

BTW, you cannot overload an Irish socket unless you've somehow bypassed the fuse in the plug. So any overheating issue is almost ALWAYS a loose connection, use of an unfused double-adaptor or some problem with the contacts in the plug / socket.

The fuse in the plug or fused-adaptor is rated 13Amps and the plug and socket should be able to comfortably carry this. If the appliance draws too much power, or if the voltage were low, the fuse would burn out as it would exceed 13amps.

This is not the case in any other system in the world as they all use non-fused plugs. So, a lot of the advice you read online is relevant to the US, Australia, Continental Europe etc. where overloading is a major issue, particularly where someone is using a multi-socket power strip. Elsewhere it's quite easy to exceed the max rating of the sockets i.e. 15A or 16A and have no MCB trip as it would possibly be rated up to 20Amp.

Bruthal

The OP replaced the plug on the vacuum cleaner though. Still happened again. Maybe the kitchen sockets are better ones if the kettle etc is causing no problems?

Or the Kettle etc is plugged in all the time, so the sockets are lasting slightly better.

The cleaner will be a lot lower a load as well though.

Solair

If that's the case, the OP needs to have the sockets investigated a.s.a.p. as they're a fire hazard. In the meantime, I would suggest not using them unattended and avoiding any high loads.

Most likely cheap, counterfeit non-stanard complaint sockets with loose springs. Or, whoever installed them did a really awful job and there are loose connections behind them.

If the sockets are not BS1363 complaint, then the OP should be able to get whoever installed them to replace them. If they've bought them unknowingly, they should be able to go after their supplier.

Bruthal

Definitely needs an electrician in to look alright. If a vacuum cleaner is causing that damage, it is a serious hazard.

The plug is a good point, im sure they said they replaced it though.

Bruthal

sincere113 wrote: »

Since this thread has gone on for far too long and you don't seem to be getting it I'm not posting here again.

Thats a shame. I was actually genuiely interested to find out more about these appliances, so maybe you should of started a new thread for a reasonable discussion about them.

Im sure there would be interest.