Thread for arguing about "Transformer or SMPS"

[bernardgreen]

A conversation today about EMI ( Electro Magnetic Interference ).

There are standards set for switching mode power supplies and many fail to obtain certification when they fail to meet these standards. By far the most failures are due to the EMI levels.

Can the merchant evade the need to obtain certification by not declaring the device as a switching mode device ?

Yes !

If the "Yes" opinion is correct then evasion of testing of "electronic transformers" for compliance with EMI standard may be happening for some brands of electronic transformers.

There are devices whose EMI levels are non compliant with the standards applicable to switched mode power supply units.

 

[flameport]

Likely that a majority of devices are not tested for EMI compliance.
Who is going to check them, or take any enforcement action?

This premium priced device clearly didn't comply:
http://www.bbc.co.uk/news/technology-38853962
even though it was from one of the world's largest manufacturers.

Even when they do comply, power supplies for lighting only remain compliant where the output wires are under a certain length.

 

[stillp]

The Regulations apply whether you call it an SMPS or an electronic transformer.
http://www.legislation.gov.uk/uksi/2016/1091/contents/made

 

[ban-all-sheds]

If the "Yes" opinion is correct then evasion of testing of "electronic transformers" for compliance with EMI standard may be happening for some brands of electronic transformers.

There are devices whose EMI levels are non compliant with the standards applicable to switched mode power supply units.

Please explain how this means that there should not be anything called "electronic transformers".

You can get to it just after you finish explaining how if we stop using the term "electronic transformers" and start saying "switch mode power supply", all the problems which arise from people not understanding the nature of SMPSs will vanish.

Feel free to be logical and to propose credible mechanisms in your explanations.

 

[Mikefromlondon]

If we remove the word "Transformer" and just call a Switch Mode Power Supply as "Electronic Power supply" then general public would know its not a transformer but a kind of electronic power supply that uses a principle known as switch mode. So all Electronic gadgets need to comply with EMC Directives, so one should not worry for interference and if one does cause any such problem, the matter should then be referred to trading standards who can then star looking into why a certain item imported into UK does not comply with. Public would not grasp the word switch mode so I propose Electronic Power supply, because electronic transformer doesn't sound too right, though we know what it means.

 

[ban-all-sheds]

"Electronic transformer" sounds just fine to me, and nobody who sees the term should assume that it is a transformer, unless they are also prepared to say this this is an unqualified "cigarette".

Will you please explain how the regulations which apply to something on the basis of what it is can be affected by what someone chooses to call it.

 

[ban-all-sheds]

Oh - and by the way - Bernard, this clutching at straws is not very edifying.

You are wrong, and every one of your arguments is broken and failed.

Give it up.

 

[Mikefromlondon]

Switch Mode Power supply in Nokia charger, as for public its just a phone charger, they need not know it has SMPS circuit inside. (I took one apart today just to see if it really had some sort of SMPS or was it a simple capacitor charge transfer device that may not provide true isolation, well i was wrong and this shows that a small SMPS can be packed in a housing as small as a plug top.
Note it is just under 2 watt SMPS providing 5v at 350mA (actual 1.75watts)
the small HF Transformer provides mains input to output isolation. It does not have a fuse but a fusable 10 ohm resistor, there is No provision for any RF filtering in it that i can see. It was from one of my tenant who came over from India and left it behind so you will notice it has no CE marking. And the plug has Indian round pins. As it has no filtering, it would most probably be illegal to use in UK.

 

[ban-all-sheds]

Switch Mode Power supply in Nokia charger, as for public its just a phone charger, they need not know it has SMPS circuit inside.

Indeed, they need not, any more than they need know that an box which says "electronic transformer" on the outside has a SMPS inside.

But so what?

there is No provision for any RF filtering in it that i can see.

Can anyone explain the mechanism which would have resulted in it having such filtering if it had been identified as a SMPS on the enclosure?

It was from one of my tenant who came over from India and left it behind so you will notice it has no CE marking.

It doesn't have to have.

As it has no filtering, it would most probably be illegal to use in UK.

Maybe it would.

Can anyone explain the mechanism which would have resulted in the owner not using it in the UK if it had been identified as a SMPS on the enclosure?

 

[Mikefromlondon]

My post was for informative purpose, not for having to explain mechanisms behind CE markings and I was merely trying to point the fact as technology has advanced, and sizes shrunk, SMPS has taken over presidence over conventional bulky transformers for running gadgets including power adaptors, phone chargers, halogen Lighting , LED lighting, almost everything now runs on electronically controlled power supplies so called switched Mode.

There is nothing to explain, the purpose of my thread was to stop people arguing about the difference between an SMPS and Conventional Transformer based power supply. Both can perform a power conversion or voltage transformation process, but one uses high frequency switching of a much smaller transformer and still convert power in exactly the same way as the conventional bulky transformer does without using HF switching but relies on mains 50/60Hz ac.

However, in practice, some applications do not perform very well when using SMPS based power supplies, these are mainly the LED lighting, particularly running on 12v supply, where the manufacturer of the 12v LED light expected his lights to be running on conventional transformer that previously ran halogen lights, but what the manufacturer did not contemplate that a customer may not be using a conventional transformer based power supply but using an electronic transformer, where his LED light would start to shimmer or start to flash as the two items start to interfere with one another due to lack of filtering and linked together.

So yes we do have a problem, problem of compatibility, I personally saw this problem when replacing a mate's 8 halogen lights with 8 LED lights designed to work on 12v ac, we ended up removing his SMPS based power units and had to use conventional 12v power supplies for which those particular LED lights were intended to be used by. This cured his shimmering problem.

This is the main reason why many people rightly say the two are not the same and perform differently, yet the energy transfer function in both uses a transformer.

 

[ban-all-sheds]

My post was for informative purpose, not for having to explain mechanisms behind CE markings and I was merely trying to point the fact as technology has advanced, and sizes shrunk, SMPS has taken over presidence over conventional bulky transformers for running gadgets including power adaptors, phone chargers, halogen Lighting , LED lighting, almost everything now runs on electronically controlled power supplies so called switched Mode.

Yes - we all know all of that, but the "argument" here is whether the ones sold for lighting should be called "electronic transformers" or "SMPSs"

There is nothing to explain, the purpose of my thread was to stop people arguing about the difference between an SMPS and Conventional Transformer based power supply.

Nobody is arguing about the differences.

Some people are arguing that they should not be called "electronic transformers" because they are not "transformers"

However, in practice, some applications do not perform very well when using SMPS based power supplies, these are mainly the LED lighting, particularly running on 12v supply, where the manufacturer of the 12v LED light expected his lights to be running on conventional transformer that previously ran halogen lights, but what the manufacturer did not contemplate that a customer may not be using a conventional transformer based power supply but using an electronic transformer, where his LED light would start to shimmer or start to flash as the two items start to interfere with one another due to lack of filtering and linked together.

Yes.

But some people here seem to be suggesting that those problems would go away if the supplies were labelled as SMPSs instead of "electronic transformers".

So yes we do have a problem, problem of compatibility

Indeed.

But those problems won't go away if we change the wording on the supplies from "electronic transformer" or "SMPS", and that is what this debate is about, so please don't be surprised if what you write is assumed to be a contribution to that debate, and not to another one.

This is the main reason why many people rightly say the two are not the same and perform differently, yet the energy transfer function in both uses a transformer.

Nobody is claiming that they are the same.


Some people are "saying" that this must not be called an "electronic cigarette" because it is not a "cigarette"

 

[bernardgreen]

Some people are arguing that they should not be called "electronic transformers" because they are not "transformers"

Some people are actually arguing that they should be called what they are so that they can be recognised as the most probable cause of the many problems that SMPS unit create when the user assumes they work as a normal transformer.

 

[Mikefromlondon]

Yes - we all know all of that, but the "argument" here is whether the ones sold for lighting should be called "electronic transformers" or "SMPSs"



Nobody is arguing about the differences.

Some people are arguing that they should not be called "electronic transformers" because they are not "transformers"

That was purely from technical point of view, not from general point of view that where the public need not know the difference between the two.
(sorry I have to use different colour to reply as I haven't worked out how to reply to your each point in quotes.)
I see their argument or point, SMPS are not quite like Transformers, so this is why they are objecting to it, but now it is far too late, across the industry it is now accepted as Electronic Transformer.





But some people here seem to be suggesting that those problems would go away if the supplies were labelled as SMPSs instead of "electronic transformers".

We and I all have to agree that Electronic Transformer is another name for an SMPS, this may help standardise things overall. Any problems associated with using such power supplies won't make them go away obviously, but knowing what exactly they employ can help in avoiding such like problems.



But those problems won't go away if we change the wording on the supplies from "electronic transformer" or "SMPS", and that is what this debate is about, so please don't be surprised if what you write is assumed to be a contribution to that debate, and not to another one.
May be I have lost the track somewhere of the argument, I think I have been confused as to exactly what the argument was about, but yes you are right that if it was about whether problems would go away if it was correctly identified as either SMPS or Electronic Transformer, in my opinion, Nope, unless the buyer of such power supplies was aware of the implications of mismatch or incompatibility issues beforehand, if he was not aware then those issues may arrise when he puts that item to use and it would be a learning curve for him.




Nobody is claiming that they are the same.

OK I thought some people were claiming they are the same, its my misapprehension, sorry.


Some people are "saying" that this must not be called an "electronic cigarette" because it is not a "cigarette"

I am a smoker, I have tried them, they don't quite feel like the real thing, they are not the same as a tobacco cigarette that you can light up, I agree and I would personally understand that these devices are called an Electronic Cigarette, in order to differentiate between real and substitute, I have accepted that this is and will be the term chosen for this device, but there will be some who may argue about its true nature, or its accepted name, they could have been called something else but that sure does not alter its function, technically it is a Nicotine Inhaler that is designed to replace a real cigarette. Perhaps a very handy device for those who are not allowed to smoke a real cigarette, but yes I agree its name would not change what it does, but for sure we cannot call it a Cigarette, we have to add something in front of it such as the term Electronic.

 

[Mikefromlondon]

Pardon me if I was confused as to what the whole argument was about as there had been many threads based on SMPS and Electronic Transformers.
We all need to accept what is becoming a general terminology for such products.

 

[ban-all-sheds]

Some people are actually arguing that they should be called what they are

They are called what they are.

They are called ELECTRONIC transformers.

so that they can be recognised as the most probable cause of the many problems that SMPS unit create when the user assumes they work as a normal transformer.

Will you PLEASE explain the mechanism by which users of them will understand that something labelled a "switch mode power supply" can create problems of which they would be unaware if it were labelled "electronic transformer".