Thread for arguing about "Transformers"

Hi Mike

Many boilers modulate their heat output by changing the speed of the fan and hence the amount of air and gas fed to the combustion chamber. Motors are typically stepper type motors with the speed control from the main control PCB.

Lots of RF radiation from the switching of the drive coils by semi-conductor switches on an often un-screened PCB in the plastic casing of the motor .
 
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You are also wrong Nozzle, its called Transformers.

just one letter can make hell of a difference!
 
Hi Mike

Many boilers modulate their heat output by changing the speed of the fan and hence the amount of air and gas fed to the combustion chamber. Motors are typically stepper type motors with the speed control from the main control PCB. Lots of RF radiation from the switching of the drive coils.

yes I agree Bernard, there are those that also have an input back from the main board and require like a 5 wire loom, and there are those that only run on 230V supply, so I was talking of the non modulating fans, these I could not believe how complex they have been made to run using a permanent magnet armature, and field coil that has a winding resistance of a few hundred ohms (typically 150-210 ohms) and are driven by a short switched pulse of 330 v DC, this high voltage DC is fed for a very brief period and a magneto sensor then detects motion (RPM) and switches the field polarity in reverse so it is effectively supplying an AC current from a high voltage switched source, on these fans there is no other input other than a magneto sensor, I do have a few modulating fans the guy brought over, and these of course would be controlled by the boiler as to how fast they need to spin at any given moment, in other words there is no point in having say a fan that draws 30watts when on lower heat output a fan using 5 watts can efficiently remove the products of combustion, so when the boiler is running at its full load, the fan may need to run much faster in order to remove greater amount of waste products, all depending of course on individual boiler design, some operate on so called positive pressure and some on negative pressure, i.e. fresh air pushed in rather than waste products sucked out, an analogy would be that you can both push a broken down car or pull it as well (towed) by another. The fans I am referring to are just basic fans without a modulating control. and if they had been made using induction motor, they would not have packed up in such a short time, and say even if you had condensate drip on them, they would have carried on functioning whereas these electronic fans just pack in.
 
And it was certainly not a joking matter for the engineer who turned out close to midnight with an hours drive to attend a failing comms wireless system to find there was nothing wrong with the wireless equipment. The failures ( corrupted data having to be repeated several times ) were due entirely to the switched mode device in a power supply for a lamp unit.
Please explain how that would not have happened if the power for the light had come from a small white box called a switch-mode power supply and not a small white box called an electronic transformer.
 
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@ BAS

The point is that an SMPS dressed in a white plastic case with Electronic Transformer printed on the case cannot be treated or used in the same way as an inductive transformer in a similar white case can be used. If you are and others like like you are going to insist that SMPSs can be called Electronic Transformers then like cigarettes have "Heath Warning" on the pack all SMPS items should have warnings on the case about the radio frequency intererence they radiate.
 
Not to someone with the same attitude as you are showing at this time
The problem is that you, and Winston, do not like the fact that SMPSs made for the ELV lighting market are called "electronic transformers".

You both keep ignoring the "electronic" part, and keep on saying "they are not transformers because they do/don't do XYZ, and transformers don't do/do do XYZ".

Winston branches off from there to claim that they simply do not exist, despite all the evidence to the contrary.

You go on about how you can get side-effects from SMPSs that you don't get from magnetic transformers, and that sometimes those side effects can be very deleterious to something, but you cannot explain (or so far have never explained) how if we stopped calling them "electronic transformers" and started calling them "switched mode power supplies" those problems would go away.

If you and W don't like the term "electronic transformer", for whatever reason(s), that's fine, but in that case you need to start a campaign within the industry to get them to stop using the term. What you must not do is to say that there's no such thing.
 
The point is that an SMPS dressed in a white plastic case with Electronic Transformer printed on the case cannot be treated or used in the same way as an inductive transformer in a similar white case can be used.
Indeed not.

Now will you please explain how all the negative consequences of thinking that they can would go away if the white plastic case said "switch mode power supply" where it currently says "electronic transformer".


If you are and others like like you are going to insist that SMPSs can be called Electronic Transformers
I'm not insisting that they can be - I am insisting that that is what they ARE called.


then like cigarettes have "Heath Warning" on the pack all SMPS items should have warnings on the case about the radio frequency intererence they radiate.
Surely if that is a useful warning to have then it should be on the items whether they are called "electronic transformers", "switched mode power supplies", or "multi-dimensional space-time transmogrifiers".

How does the worth and validity of such a warning depend on the name given to the device?
 
You both keep ignoring the "electronic" part, and keep on saying "they are not transformers because they do/don't do XYZ, and transformers don't do/do do XYZ".

You are the one ignoring the electronic part, the electronics that :-

1/ create interference to other equipment.
2/ produce large voltage spikes that may damage the equipment being fed by the SMPS {*}
3/ create ultra sonic noise that disturbs / irritates animals
4/ may not provide adequate isolation between input ( 230 volts mains ) and the ELV output


(*) I think one of the graphs shows these, often a sampling / digital scope does not pick up these transient spike ( a few nanoseconds long ) but they do damage the device being fed.
 
You are the one ignoring the electronic part, the electronics that :-

1/ create interference to other equipment.
2/ produce large voltage spikes that may damage the equipment being fed by the SMPS {*}
3/ create ultra sonic noise that disturbs / irritates animals
4/ may not provide adequate isolation between input ( 230 volts mains ) and the ELV output
It's not just SMPS that can do (most) of the above. The transformers I work with can certainly create interference to other equipment. You are not allowed near one if you have a pacemaker and they can also play hell with computer equipment. They may not produce ultra sonic noise but the hum that some create can actually be felt. Then again, they are quite big. This is quite a small one. I'm the guy kneeling down with a big arrow pointing to me. The arrow isn't real by the way, at least I've never seen them hovering over transformers :)
didcot.jpg
 
You are the one ignoring the electronic part
Indeed.

Every time I point out that they are ELECTRONIC transformers when people say "No, they can't be transformers because...", I am the one ignoring the "electronic" part.

That makes perfect sense.


1/ create interference to other equipment.
Indeed they do, or can.

Will you please explain why those electronics would no longer create interference if the case they were in said "switch mode power supply" instead of "electronic transformer" and that therefore what they are called is intrinsic to the problems they can create, and which, therefore, is the reason they should not be called electronic transformers.


2/ produce large voltage spikes that may damage the equipment being fed by the SMPS {*}
Indeed they do, or can.

Will you please explain why those electronics would no longer produce large voltage spikes if the case they were in said "switch mode power supply" instead of "electronic transformer" and that therefore what they are called is intrinsic to the problems they can create, and which, therefore, is the reason they should not be called electronic transformers.


3/ create ultra sonic noise that disturbs / irritates animals
Indeed they do, or can.

Will you please explain why those electronics would no longer create ultra sonic noise if the case they were in said "switch mode power supply" instead of "electronic transformer" and that therefore what they are called is intrinsic to the problems they can create, and which, therefore, is the reason they should not be called electronic transformers.


4/ may not provide adequate isolation between input ( 230 volts mains ) and the ELV output
Indeed they may not.

Will you please explain why they would always provide adequate isolation if the case they were in said "switch mode power supply" instead of "electronic transformer" and that therefore what they are called is intrinsic to the problems they can create, and which, therefore, is the reason they should not be called electronic transformers.
 
Are you trying to be a wind up merchant.

If they were called switch mode power supplies then people considering using them might be aware of the problems that an SMPS brings with it. The terms "electronic transformer avoid raising concerns that an SMPS has.
 
Are you trying to be a wind up merchant.
Not at all.


If they were called switch mode power supplies then people considering using them might be aware of the problems that an SMPS brings with it.
I see.

So the average consumer who goes into a DIY shed, or a lighting shop, or shops online, sees an item called a "switch mode power supply" and he would, or might, be aware of the problems that they can bring with them.

Will you please explain the mechanism by which he would have acquired that awareness?
 
Generally speaking, SMPS can mean anything, for example it can mean Scottish Members of Parliament Seminar, or Switched Mode power supply.

but Technically speaking SMPS is not quite like a conventional bulky wound iron core transformer, but because it uses high frequency chopping circuit (Electronics) it can it cane therefore perform a function that a conventional Transformer did for a particular application.

These days the trend is now to use SMPS in nearly everything from mobile phone chargers to you name it.

General public would not have a clue what SMPS stands for, they would go to a electrical store to buy LV Lighting, and they may ask the assistant for a suitable LV transformer, and the assistant may then fetch a low voltage (usually 12v) power supply, and place it on the counter, and when the customer picks it up and he gets amazed as to how light weight it is, most people are used to conventional low voltage power supplies using bulky and heavy iron core transformers, so now the store assistant tells the customer yes it uses Electronics and uses latest technology and so is lighter and cheaper and compact, and he may then tell the customer we call them electronic transformer.

Essentially speaking an SMPS is no where near comparable to a conventional Transformer except it can perform a same function that is to provide or convert Mains 230V AC into lower 12V or any other voltage and specified current.

Let us for now leave the LED lighting out of this Argument,since the LED lighting itself is very varaying and complex, some require 12V DC, others require constant current source, some don't even require a LV power source as they have built in power supply and can run directly off the mains 230V. Overall most power supplies used for running LOW VOLTAGE lighting are now manufactured using SMPS technology. Its main advantage being that it is light, efficient, generates less heat, and is compact, but it also emits some unwanted radiation (Electromagnetic interference) but this is kept to a minimum, and has to meet strict EEC Directives on EMC electromagnetic emissions, or else they will not be approved and given a certificate of conformity, and therefore legally cannot have a CE marking and sold in Europe legally.

So for most purposes, these SMPS are ok, they don't generally cause any harmful electromagnetic emissions and so most of your other equipment will not be effected by them unless they had developed a fault.

Most consumer goods now also run on SMPS, be it a PC, laptop, mobile phone chargers, video/dvd player, blue ray, washing machines, tumble, CH boilers, Nest controllers, anything for that matter, but general public doesn't need to know what kind of power supply their washing machine control board is running off, the days of bulky transformers are now numbered.

Though I hate to say, SMPS are far more unreliable than conventional transformers, and can tolerate less abuse.

So yes both Bernard Green and Winston are correct that the two are not the same, and I agree they are world apart, but for general public SMPS could mean anything, so instead many manufacturers started to call them Electronic Transformers, however, call them what anyone likes, including LED drivers.

The argument is pointless, an SMPS is not a Transformer, but it does a similar function, its like Doctors call a Transient Ischemic Attacks (TIA), for general public they have no idea what a TIA is and so it is referred to as a Mini Stroke. All Electronic Engineers will certainly know the difference between an SMPS and a Transformer they indeed are world apart.

Further more almost all SMPS use a small HF Transformer, its function within SMPS is almost same as in a conventional Transformer, but it is only needs to be a lot smaller for the same givcen power transfer.
1. For providing mains isolation
2. For converting HV mains to Low voltage DC, but at much much higher frequencies, hence why you would only need a small size transformer as opposed to a bulky iron core transformer.

Almost all SMPS provide means of input - output isolation, some very cheap mobile chargers with 3 pin plugs may not be true SMPS as they may employ a charge transfer using capacitor with its DC Negative rail being common with supply neutral, these can be lethal if the mains wiring was reversed, and can provide a fatal shock. Although I have not yet taken any apart to study them, but I cannot see how they can pack a true SMPS circuit in a size of case no bigger than a 3 pin plug. I will probably start taking some apart to see if they do contain any isolating transformer within them or do they just rely on some other factor to avoid giving consumers any shock.

The fact that even retailers of LV Lighting might get confused of you went into a store and asked for a Switched Mode Power Supply, they may raise their eyebrows? and may ask you if you mean 12V power supply for lighting, and so on.

Only the Electronic Engineers or those who studied the subject would truly know the true nature of SMPS and Transformer.

So a Transformer is not an SMPS and an SMPS is not a Transformer.
 
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This is more of an attempt at a summary than a reply specifically responding to MFL's post.

So a Transformer is not an SMPS and an SMPS is not a Transformer.
And nobody is claiming that it is, or they are.

Yes - the great unwashed refer to those little lightweight efficient bricks which power their lights as "transformers". But then they also call the lights "low voltage".

And in their world those things don't matter, and in their world they aren't going to get bitten by their incorrect terminology. When people rock up here I do think it can be worthwhile referencing the ELV/LV difference, purely because if they do ever look at the law they might get confused and think it doesn't apply to them if they have no 12V lighting.

I have no problem with the term "electronic transformer", for 2 reasons:

  1. They do transform voltage, and there is no requirement that a change has to be potential difference only and not frequency, or that the device can be operated in reverse, for the word "transformer" to appear anywhere.
  2. The modifier "electronic" is sufficient to show that it is not a "transformer", in just the same way that an "electronic cigarette" is not a cigarette, and an "electronic book" is not a book. They all produce the same effective results - an e-cig delivers nicotine to be absorbed via the lungs, it just does it differently, and with different consequential side effects to a cigarette, just as an electronic transformer delivers a changed voltage and with different consequential side effects to a transformer. Moving away from their designed method of use you can't do with an e-cig what you can do with a cigarette. And vice versa.
An e-book delivers printed words to be read, it just does it differently, and with different characteristics to a book. Are they interchangeable with no regard to their differences? No. You might not be thanked for trying to use a Kindle to prop up a wonky table leg, or you might not be thanked for stuffing 50 (number picked at random, I really HNI) paperback books into your hand luggage.​

Nobody is claiming that an "electronic {whatever}" is he same as a "{whatever}", or that a simple "{whatever}" should strictly be used when what is meant is an "electronic {whatever}".

But we have a problem here with a couple of members. One is so rabidly opposed to the term "electronic transformer" that he claims that there is no such thing, that people who use the term have no idea what they are talking about, and he goes on and on and on and just will not stop no matter what DIYnot tries to do. (Which is not enough, IMO).

The other seems to think that if we could persuade everyone to stop using the term, and start to use "switch mode power supply" instead then all of the problems which arise from people not understanding the potential side-effects of SMPSs would go away, because they would know what the little lightweight efficient bricks which power their lights really were, but he has been unable to explain just how that would be the result.

So, when people come here and talk about their "transformers", should we delve into the "are they transformers or electronic transformers?" issue? Maybe, if it matters (e.g. with dimming capabilities, minimum loads, powering a different lamp type to the one they're designed for etc).

Should we go down the "No, they are not transformers and they are not 'electronic transformers' because they don't exist, they are switch mode power supplies" route? No, never.
 
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Let me give you another example what SMPS means in todays world, remember years ago we had cars that had an ignition coil, (which is actually a form of Transformer for stepping up 12v DC to 10 thousand volts High tension voltage! and a Distributor with contact breaker and a condenser, and then it was a mechanically turned by a drive system through camshaft gears, and had a rotor to distribute spark to correct spark plug according to engine firing order.

Then as the technology started to advance, the contacts were replaced by a so called Transistor switch, many manufacturers started calling them Transistor Ignition, some calling it transistor assisted ignition system, and then some started to call it Electronic Ignition! some started to call it breaker less ignition system, some capacitor discharge ignition system, This brought about more reliability as the mechanical contacts had limited life due to metal erosion and needed regular cleaning and setting of the gap to give the correct dwell angle for engine to perform at its peak performance, also pitted contacts caused misfires and loss of some engine power due to weak spark caused by badly pitted contacts..

later on as the technology advanced more, car manufacturers realised that they can do away with a distributor altogether, and can generate a spark using an ignition coil feeding the required cylinder directly, without the need for a rotor! and so they came up with a solid state ignition system, where there are no moving parts and so the reliability jumped many folds, it got rid of a distributor, rotor, contacts, and so a new system called wasted spark ignition arrived, today most cars use this system, and so as it is now widely accepted by all car buyers and manufacturers, there is no need to advertise that a particular car is superior because it uses solid state ignition system.
 
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