multi DC out put 12V in transformer wanted

[AstonHill]

I remember a while ago now buying one form a petrol station. you would plug it into the cigarette lighter plug of a car and you could set its output by a dial of a switch to say, 9, 6 or 3 volts

Sadly an internet search I cant find anything. So first off; anyone know what one of these things aew called please?

 

[JohnW2]

I remember a while ago now buying one form a petrol station. you would plug it into the cigarette lighter plug of a car and you could set its output by a dial of a switch to say, 9, 6 or 3 volts ... Sadly an internet search I cant find anything. So first off; anyone know what one of these things aew called please?

You mean something like this (see here) - which seems to offer outputs of 1.5, 3, 4.5, 6, 7.5, 9 & 12 volts?

Kind Regards, John

 

[AstonHill]

You mean something like this (see here) - which seems to offer outputs of 1.5, 3, 4.5, 6, 7.5, 9 & 12 volts?

View attachment 314542

Kind Regards, John

Yes that is perfect!
Any idea where i can buy it form a proper shop?
Thanks

 

[AstonHill]

You mean something like this (see here) - which seems to offer outputs of 1.5, 3, 4.5, 6, 7.5, 9 & 12 volts?

Well maybe not; just to muddy the waters hear

My laptop says it is 15V DC input charge. So instead of going from my 12V car battery my DC-AC invertor which seams to make a lot of noise when doing very little! Then going to my laptops DC-AC adapter. I would like to bypass all of this and save power!

So from my DC system I have a 24V out put (2x led acid batteries wired in series) and if I plug the "DC multi voltage adaptor/ regulator" into it then i would need a setting of 7.5 volts right (7.5vX2=15V/ 12vX2=24V) But the setting on it are 9, 7.5, 6 est. Should this work?
Thanks

 

[JohnW2]

Yes that is perfect! ... Any idea where i can buy it form a proper shop? ... Thanks

You're welcome, but I've no idea what you would regard as a 'proper shop' - if you buy "it", presumably it will be the same wherever you get it from? (I know you have issues with multiple suppliers, but that's your problem!).

If you search for it by name seemingly "Roadster") you might find another source. I had no problem finding that one with Google - there are a lot of similar products out there.

Kind Regards, John

 

[JohnW2]

Well maybe not; just to muddy the waters hear ... My laptop says it is 15V DC input charge. So instead of going from my 12V car battery my DC-AC invertor which seams to make a lot of noise when doing very little! Then going to my laptops DC-AC adapter. I would like to bypass all of this and save power!

That's all very different from what you asked about, and I don't understand much of it - in particular, what you mean by your laptop's "DC-AC adapter" - do you mean "AC->DC adapter" (which is what laptop power supplies are)?

So from my DC system I have a 24V out put (2x led acid batteries wired in series) and if I plug the "DC multi voltage adaptor/ regulator" into it then i would need a setting of 7.5 volts right (7.5vX2=15V/ 12vX2=24V) But the setting on it are 9, 7.5, 6 est. Should this work?

Again, you seem to be making this very complicated - why two 12V batteries in series? If you again ask Mr Google the actual question , you will find plenty of adapters designed to run from a single 12V battery (via a car cigar lighter socket) specifically to provide the voltage (19V, 20V or whatever) required for a laptop.

Kind Regards, John

 

[flameport]

anyone know what one of these things aew called please?

They are called cheap crap which will damage and destroy expensive electronic devices which are connected to it.

Depending on what laptop you have got, it may not be a case of just shoving 15V or whatever into it either.

 

[SUNRAY]

This is the sort of thing you should be looking at: https://uk.rs-online.com/web/p/car-...6H1FDi3-g9gIgEh7k-EaAqdDEALw_wcB&gclsrc=aw.ds

This happens to be a 19V version but was very first hit on google for : 12v dc to charge laptop adapter

 

[JohnW2]

This is the sort of thing you should be looking at: https://uk.rs-online.com/web/p/car-chargers/0417916?cm_mmc=UK-PLA-DS3A-_-google-_-CSS_UK_EN_Power_Supplies_&_Transformers_Whoop-_-Car+Chargers_Whoop-_-417916&matchtype=&pla-298647443996&gclid=Cj0KCQjw9rSoBhCiARIsAFOiplnJupSUBUFSpGo-gAaeeKsxLwAAOtpPzHhm6H1FDi3-g9gIgEh7k-EaAqdDEALw_wcB&gclsrc=aw.ds

Indeed. I'm not sure whether that will get described as "expensive crap" or what, but I would personally be fairly happy using it with my laptop!

I have to say that I do find some of the 'sweeping generalisations' we see being made to be rather irritating.

Kind Regards, John

 

[SUNRAY]

Indeed. I'm not sure whether that will get described as "expensive crap" or what, but I would personally be fairly happy using it with my laptop!

I have to say that I do find some of the 'sweeping generalisations' we see being made to be rather irritating.

Kind Regards, John

I have to agree with that although in this case I wouldn't dispute the comment, A little while back (possibly >2 years) the statement of something to the effect of 'non compliant junk' in relation to a split load board (something like BG). When questioned the response was to the effect the RCD's are only 63A and no SPD... so perfectly compliant.

 

[JohnW2]

I have to agree with that although in this case I wouldn't dispute the comment, A little while back (possibly >2 years) the statement of something to the effect of 'non compliant junk' in relation to a split load board (something like BG). When questioned the response was to the effect the RCD's are only 63A and no SPD... so perfectly compliant.

Yes, it the strong assertions we often see (seemingly 'knee-jerk generalisations') that certain things are "dangerous junk", "non-compliant tat" etc. etc. that annoy and irritate me a bit, particularly when they come from someone whose opinion is, for very good (other) reasons, very much respected by many people.

It's difficult, since there obviously are some rogue products ("dangerous tat") but it the 'generalisation' that troubles me.

I think attitudes to products and 'shopping' is changing (particularly in our financially difficult times) such that people are coming to understand that 'cheap' and/or 'unfamiliar brand' do not necessarily mean anything more than that the 'reputable brand' manufacturers are making vast profits at consumers' expense. A few decades back, like many people, I bough 'expensive and reputable brand' products because I assumed that they were 'better'. However, over the decades I have come to realise that cheap does not necessarily mean 'nasty', and these days buy a lot of extremely cheap products, with which I am usually very happy. Even if they have much shorter lives (which, in my experience, is rarely the case), then if they only cost a fraction of the price of a 'reputable brand' product, it is still financially advantageous to go with the cheapo!

Kind Regards, John

 

[SUNRAY]

Personally I'm finding more problems with the expensive/better quality products than the budget versions, however one has to assume there is more of the expensive items in use than cheap and the apparent failure rate may appear to be biased.

I regularly use BG and ProElec CU's when space is at a premium and to date not encountered any issues and all the test results have been fine.

 

[JohnW2]

Personally I'm finding more problems with the expensive/better quality products than the budget versions, ...

As I've said.my experiences have been similar. In particular in the case of LED lamps/bulbs, I've had far more reliability (longevity) problems with expensive ('reputable brand') ones than from 'the cheapest and most anonymous I can find'.

however one has to assume there is more of the expensive items in use than cheap and the apparent failure rate may appear to be biased.

I'm not even sure that you assumption is necessarily correct but, even if it is, it would not affect/'bias' the 'failure rate'. However, for an electrician who only gets called to see items which have problems, he/she would obviously see more of those which were more commonly in service, even if the failure rate was no different from that o the less common ones.

I regularly use BG and ProElec CU's when space is at a premium and to date not encountered any issues and all the test results have been fine.

I presume you are talking about devices, and primarily RCDs (and thee residual current functionality of RCBOs), since MCBs are essentially not testable (and very rarely 'fail' in the sense of bursting into flames/whatever) and I can think of nothing else about a CU which could 'fail' or affect test results?

Kind Regards, John

 

[robinbanks]

Well maybe not; just to muddy the waters hear

The search term you need is "dc to dc converter" or "dc to dc power supply" - look for one that is the exact voltage pairing you require and can handle the max current the laptop will draw. Bear in mind that (as evidenced from your earlier threads on other topics) you don't seem to understand things like voltage, current, power, ac, dc, parallel and series etc very well, so it might be worth asking here whether any proposals for kit you find will work out. For example, your proposal to wire the outputs of two cigarette adaptors configured for 7.5v in series to power your 15v laptop would be highly unlikely to deliver the required current. At best they'd burn the fuse, at worst the house.

Further to this, I suspect you'll find that tha efficiency difference between the DC/DC route of your idea, and the AC/DC route of your laptop power supply will be negligible, if it's in favour of the DC/DC route at all. Don't lose sight of the fact that a small efficiency difference has to pay for the converter, which may take a long time.

I also suspect this quest will turn out to be a similarly hare-brained goose chase as the Aldi grinder battery was

 

[SUNRAY]

As I've said.my experiences have been similar. In particular in the case of LED lamps/bulbs, I've had far more reliability (longevity) problems with expensive ('reputable brand') ones than from 'the cheapest and most anonymous I can find'.

I'm currently using some LED G9's somewhere in the middle, The initial cheap versions seemed to be failing within a few working hours in 3x 3arm fittings, within 6 months (or so it feels now) all 9 had failed and Energiser replacements did the same, I think another 'good' set did something similar. Currently using some 'middle of the road' bulbs pricewise - possibly Family/Home Bargains which have outlived all the others. Bear in mind one of the original 60W GLS bulbs had been there for over 20 years before the new lamps were installed and the other 2 had not been replaced more than twice.

I'm not even sure that you assumption is necessarily correct but, even if it is, it would not affect/'bias' the 'failure rate'. However, for an electrician who only gets called to see items which have problems, he/she would obviously see more of those which were more commonly in service, even if the failure rate was no different from that o the less common ones.

Yes that was what I was trying to say

I presume you are talking about devices, and primarily RCDs (and thee residual current functionality of RCBOs), since MCBs are essentially not testable (and very rarely 'fail' in the sense of bursting into flames/whatever) and I can think of nothing else about a CU which could 'fail' or affect test results?

Kind Regards, John

Yes essentially the contents of the CU's as all the other tests would essentially relate to the circuits.
Why do you say MCBs are essentially not testable?