Cable length with lighting inverters

[JohnW2]

I think you have hit the nail on the head. As long as the name differentiates between an inductive transformer and another device then not so bad.

Quite so.

However well before the lighting manufacturer started making switch mode high frequency devices to power 12 volt lights the welding machine manufactures started to produce the inverter which replaced the welding transformer giving far better control with a better feel and much lighter. ... Since the name "Inverter" has already been used to describe these devices I see little point in using another name for basic same device. ... Be it to raise or lower the voltage the electronic device to replace the transformer as been called an inverter. Often used with DC input to raise the voltage. In the old days it was called a rotary converter we also had the synchronous vibrator with transformer to raise voltage in the old days.

Indeed. I was brought up on DC-DC inverters (usually 12V in and around 250V-300V out), used to power valve-based equipment from car batteries - and I still have examples not only of them but also of both rotary converters and synchronous vibrators somewhere in some dusty corner of my cellar! However, those 'inverters' I built and used were not really SMPSs in the modern sense - they were 12V roughly sine-wave oscillators which fed a step-up true (inductive) transformer and rectifier/regulator - and necessarily at quite low frequency (hence large transformers), since the power transistors of the '60s could not cope with much in the way of frequency! Rotary converters were somewhat similar in concept, but the vibrators+transformers were, of course, an early electro-mechanical version of an 'SMPS'!

My thanks to point out the 2 or 4 meter limit also the frequency at 40 kHz amateur radio starts at 136 kHz so unlikely to cause interference.

You're welcome. The amateur service is obviously not the only one to be considered - but I think the main point is that any wiring would be so short in comparison with the wavelength at 40Hz that any radiation, hence possible EMC, would be minimal.

Some of the HF fluorescent units go into the Ghz range so very different.

Do they really? That sounds rather crazy, and I find it hard to see why they would do that!

Kind Regards, John

 

[EFLImpudence]

People are confusing the definition of a word and the description of one device which achieves the objective.

A car is a device which transports people between places.
It is not only a four-wheeled machine powered by an internal combustion engine - a description of one type of car.

 

[JohnW2]

People are confusing the definition of a word and the description of one device which achieves the objective. A car is a device which transports people between places. It is not only a four-wheeled machine powered by an internal combustion engine - a description of one type of car.

In context, I'm not so sure about that. As I wrote yesterday, if one uses the word 'transformer' to refer to any device that 'transforms' something into something else (indeed, even if one restricts it to transforming electrical energy), it would cover a high proportion of the the everyday things we know and love.

Indeed, in terms of things electrical, virtually any useful appliance/load 'transforms' electrical energy into something else - heat, light, movement etc., but it would not, IMO, be useful or sensible to call them all 'transformers'!

Kind Regards, John

 

[ericmark]

In the main the Ghz range was used for 12vdc units fitted to caravans the transformer looked more like a choke and designed so load would lower the voltage dramatically typical no load 300 volt on load down to around 60 volt they did not use the heaters in the tube the clip went over both the heater pins as one.

I would look for the older type which used tapping on the end of the transformer for heaters again voltage would drop on striking but more like 180 volt open circuit and 60 volt run with of course similar for heaters with 6 volt at start but still 2 volt on heaters when running. Clearly used more power but less RF interference with lower frequency being used.

The no maintainable units with many devices integrated into the same package has resulted in confusion as to their suitability as other things change. The main problem with lighting has been the use of switch mode method of regulation which in the main means a minimum current must be drawn. The same problem exists of course with other power supplies and so we need a way to with easy identify what is being used.

There is a general lack of information the lamps are just as bad with simple 12 volt no maximum or minimum given with 12vac having a peak voltage of 17 volt where the lamp is clearly ac/dc as pins not marked it does need the information as to is 17 volt will damage them.

 

[EFLImpudence]

if one uses the word 'transformer' to refer to any device that 'transforms' something into something else (indeed, even if one restricts it to transforming electrical energy), it would cover a high proportion of the the everyday things we know and love.

So, which noun derives from transform if not transformer?

Indeed, in terms of things electrical, virtually any useful appliance/load 'transforms' electrical energy into something else - heat, light, movement etc., but it would not, IMO, be useful or sensible to call them all 'transformers'!

Nevertheless.

Such are the vagaries of language.
It depends what we are used to calling things.

When I have found a fault I then 'transform' the circuit by being an 'electrical rectifier'.
Thus, I am at the same time both a transformer and a rectifier.

 

[JohnW2]

Indeed, in terms of things electrical, virtually any useful appliance/load 'transforms' electrical energy into something else - heat, light, movement etc., but it would not, IMO, be useful or sensible to call them all 'transformers'!

Nevertheless. Such are the vagaries of language. It depends what we are used to calling things.

Precisely. One simply cannot (as you and others have tried) rely on dictionary definitions in such situations - one has to go by 'common/accepted usage', if necessary regardless of what dictionaries say. It would clearly be ridiculous to call most electrical appliances/loads 'transformers' - and, of course, no-one actually does that!

Kind Regards, John

 

[plugwash]

Precisely. One simply cannot (as you and others have tried) rely on dictionary definitions in such situations - one has to go by 'common/accepted usage'

The problem comes when people from different backgrounds start communicating with each other or reading documents for each other and you get confusion and misunderstandings due to them using the same terms with different meanings. Someone who has grown up under the understanding that "transformer" means a magnetic device with certain characteristcs used to convert between voltages may make unwarranted assumptions when they come to a device that is described as a "transformer" but is actually a switched mode converter.

Similarly when a power distribution engineer writes "low voltage" it's obvious to him that it means "voltages in the band that the IEC call low voltage" but give that document to a layman or an electronics engineer and they are very likely to misinterpret it.

The no maintainable units with many devices integrated into the same package has resulted in confusion as to their suitability as other things change. The main problem with lighting has been the use of switch mode method of regulation which in the main means a minimum current must be drawn. The same problem exists of course with other power supplies and so we need a way to with easy identify what is being used.

A minimum load requirement is generally indicative of a poor design where the manufacturer couldn't be bothered to cover the corner cases.

 

[JohnW2]

The problem comes when people from different backgrounds start communicating with each other or reading documents for each other and you get confusion and misunderstandings due to them using the same terms with different meanings.

Definitely - and the problem quite often is that, rather than come up with a new word, some specialist area has taken over a word that already had an established meaning in everyday language (or some other specialised area) and assigned it a specific meaning in relation to their field.

There are examples in many fields. You mention LV/ELV. I often cite 'continuity testing' and 'terminating'. Goodness knows why light bulbs became lamps, causing me to have to ask for a lamp to put in my table lamp or standard lamp Moving away from electricity, there are words like 'hysteria' and 'fracture', often/usually used with different meanings by the general public and 'specialists'. We really need cross-speciality clarity of meaning!

Someone who has grown up under the understanding that "transformer" means a magnetic device with certain characteristcs used to convert between voltages may make unwarranted assumptions when they come to a device that is described as a "transformer" but is actually a switched mode converter.

Indeed, and I am one of those people who have grown up with that understanding. That's why I am unhappy about the unqualified use of the word 'transformer' to refer to a SMPS; as I've said, I have no great problem with 'electronic transformer'. What matters is clarity, not semantics or pedanticism.

Similarly when a power distribution engineer writes "low voltage" it's obvious to him that it means "voltages in the band that the IEC call low voltage" but give that document to a layman or an electronics engineer and they are very likely to misinterpret it.

Indeed, and I personally think that this is a bad one, since it's potentially dangerous. Probably since electricity first showed itself in this world, the vast majority of the population have had a notion of what 'low' and 'high' voltage meant, with many/most of them believing that the former was relatively harmless. The organisations who (subsequently) decided to define LV to include voltages which definitely can (and sometimes do) kill have, IMO, got quite a lot to answer for!

Kind Regards, John

 

[ericmark]

I remember hearing the work force was to be decimated and I commented not as bad as I expected as I was under the impression it meant kill one in ten but was in general used to mean get rid of one in ten. Coming from the Latin from the days of the legionnaire where when they lost a battle they would kill one in ten to make them fight harder. And in my old dictionary that was the meaning.

However it seems to have some how reversed and become to mean get rid of nearly everything.

English it would seem is very different to other languages where the dictionary is written to tell people what the word likely means rather than what the word should be used to describe.

The Bible and Koran have both suffered due to language change the Bible is re-written every so often to correct where words have changed but in doing so the changers have been able to warp it's meaning. The Koran can't be translated or re-written but that also causes problems where the word its self has changed.

BS7671 has to some degree realised this problem and has included "Definitions" however these are limited and transformer is not included. This was one of the problems with Part P they did not use the same "Definitions" as BS7671 where a FCU was not deemed to have formed a new circuit.

My granddad had a lamp which would be taken off the spigot to be lit and then replaced be it an oil lamp, gas lamp or combination carbide lamp or miners lamp the lamp always refers to the complete assembly in fact with auto electrics order a head lamp and it normally will not include the bulb.

Clearly bulb refers to shape and some one wanted a word that included tubes and bulbs but instead of inventing a new word stole a word already in use just like with the transformer.

The problem is of course the LED bulb. Before the LED bulb the fact that an electronic unit had a minimum wattage was not a problem. But with LED you can swap a MR16 bulb in two identical lamps and one will work and the other will not and the fact the unit is not always need the lamp and records are pour means that all too often people replace a bulb and it will not work and they have no idea why.

They then come on a forum like this and ask questions but then English becomes a major problem. I do try to say fused connection unit (FCU) but with a residual current device I just call it a RCD unless on a boat forum where it also means recreational craft directive.

 

[stillp]

One simply cannot (as you and others have tried) rely on dictionary definitions in such situations - one has to go by 'common/accepted usage', if necessary regardless of what dictionaries say.

One can, and indeed should, provided that there's a suitable specialist dictionary, such as (for electrical terms) the IEV, or the various medical dictionaries, dictionaries of drug names and chemical names.

 

[EFLImpudence]

I think that is my point.

A transformer is something which transforms (in this case voltage).

That new kinds of transformers have been invented since the original wire-wound ones were described means that we now have to distinguish between them; not that the new ones aren't transformers.

Hence the manufacturer calls them electronic transformers; therefore that is what they are - they do contain a transformer (in the original sense).

Had the manufacturer, in order to distinguish between them, called them electronic sausages then Winston would have to keep reminding us that they were not because a sausage contains meat.

 

[JohnW2]

One simply cannot (as you and others have tried) rely on dictionary definitions in such situations - one has to go by 'common/accepted usage', if necessary regardless of what dictionaries say.

One can, and indeed should, provided that there's a suitable specialist dictionary, such as (for electrical terms) the IEV, or the various medical dictionaries, dictionaries of drug names and chemical names.

My point was that what always matters is effective, clear and unambiguous communication, taking into account who is being communicated with. It's all very well having specialist dictionaries but the terms they contain may be totally ineffective as a means of clear communication, particularly with non-specialists, if they differ from 'common usage' on the part of those being communicated with.

In terms of the two disciplines you cite, "Low Voltage" and "hysteria" have already been mentioned. In both cases, reliance on specialist dictionary definitions will mislead a high proportion of non-specialists - so one really cannot (or should not) attempt to communicate using specialist dictionary definitions without considering whom one is trying to communicate with.

Kind Regards, John

 

[JohnW2]

I think that is my point. A transformer is something which transforms (in this case voltage). That new kinds of transformers have been invented since the original wire-wound ones were described means that we now have to distinguish between them; not that the new ones aren't transformers. Hence the manufacturer calls them electronic transformers ....

That's what I've been saying - so long as wording is used which distinguishes the different sort of devices, it's fine. Hence, as you say, 'electronic transformer' is a fair enough a name for a SMPS (although I personally think it would be far better/simpler to just call them 'power supplies', which is what I'll always think of them as!), but the unqualified word 'transformer' is a different matter - because, for better or for worse, at least the older people around will assume that, when used without qualification, the word refers to a wire-wound component.

Kind Regards, John

 

[Robin0577]

Are we not overlooking the fact that the vast majority of switch mode power supplies still contain a wirewound transformer as a central component, the main point of producing the higher frequency AC being to enable the use of a smaller, lighter, more efficient transformer, often replacing the laminated iron core with a ferrite dust core?

 

[JohnW2]

Are we not overlooking the fact that the vast majority of switch mode power supplies still contain a wirewound transformer as a central component, the main point of producing the higher frequency AC being to enable the use of a smaller, lighter, more efficient transformer, often replacing the laminated iron core with a ferrite dust core?

I can't speak for anyone else, but I'm certainly not overlooking that fact.

However, just because one of these units contains a wire-wound transformer as the main voltage-changing component does not necessarily make it reasonable to call the whole unit 'a transformer'.

The main functional component in a computer is the CPU, but we don't call the whole thing 'a CPU'.

Kind Regards, John