Braun shaver power cords (AC & DC) questions
DaveC
Newsgroups: sci.electronics.repair
The Braun rechargable shaver I bought comes with a detachable 120VAC cord.
The instructions say that a 12VDC automotive cord is available for the car
cigarette lighter.
I presume that the automotive cord doesn't convert 12VDC to 120VAC, but that
the shaver's charge circuit is dual-voltage, switching between these voltages
as appropriate. My guess is that the 12V cord is straight-through from
cigarette ligher plug to the shaver.
My problem is with the word "guess". I'd like to get this bit of information
confirmed before I make my own DC power cord and plug it in. Braun customer
service can only inform me that the cord is available and of the price. No
technical details are available.
Also, I note that neither the AC power cord nor power cord recptacle on the
shaver is keyed, so I again presume that polarity of the DC cord isn't
important and that the shaver's charge circuit switches polarity as needed.
Any assistance in getting a confirmation of my guesses would be greatly
appreciated.
Thanks, Dave
Scott MacLean
figures it out for itself what to do with it.
"DaveC" <an...@me.invalid> wrote in message
news:01HW.B91A48890...@news.dnai.com...
Daniel
> Yup. My Braun shaver takes from 12V to 240V, AC or DC, any polarity, and
> figures it out for itself what to do with it.
>
> "DaveC" <an...@me.invalid> wrote in message
> news:01HW.B91A48890...@news.dnai.com...
>> From: DaveC <an...@me.invalid>
>> Newsgroups: sci.electronics.repair
>>
>> The Braun rechargable shaver I bought comes with a detachable 120VAC cord.
>> The instructions say that a 12VDC automotive cord is available for the car
>> cigarette lighter.
>>
>> I presume that the automotive cord doesn't convert 12VDC to 120VAC, but
> that
I use the 7570 with the cleaning station. The unwieldly AC plug actually
contains a voltage converter. It puts out 12V DC at 400 ma. The shaver
itself does not handle the various voltages.
My other Braun has a built in charger. It will take multiple voltages.
I'm pretty sure that they use rectifier bridge to get the right polarity
to the right spots.
--
Daniel B. Suthers, CCP
E-mail: d...@tanj.com
Web: http://www.tanj.com/
- Youth is a difficult time... it gets tougher the longer you draw it out.-
yoleus
"Scott MacLean" <sco...@spamnerosoft.com> wrote in message
news:a48J8.7749$t97.1...@news20.bellglobal.com...
> Yup. My Braun shaver takes from 12V to 240V, AC or DC, any polarity, and
> figures it out for itself what to do with it.
What a stunningly original idea !
If only a few other manufacturers would realise how easy it is to make their
systems run off multiple voltages. Braun are being quite clever accepting
dc sources as well as ac, but it is pretty trivial to to make equipment work
off US and European voltages. Nevertheless even obviously portable, travel
oriented equipment like minidisc players often lack this ability.
For most low power devices, you could just overrate a 78XX regulator and
drop twice the power when running off a 240v supply. For anything with a
switching mode power supply it should be just as easy.
I suppose the manufacturers would lose the ability to sell you a travel
adaptor.
Ian Stirling
>
>
> "Scott MacLean" <sco...@spamnerosoft.com> wrote in message
> news:a48J8.7749$t97.1...@news20.bellglobal.com...
>> Yup. My Braun shaver takes from 12V to 240V, AC or DC, any polarity, and
>> figures it out for itself what to do with it.
>
> What a stunningly original idea !
> drop twice the power when running off a 240v supply. For anything with a
> switching mode power supply it should be just as easy.
For a linear PSU, you'd increase the size.
Need a higher voltage cap (with same ESR), and about double the size of
transformer.
For real low-power, this wouldn't matter of course.
--
http://inquisitor.i.am/ | mailto:inqui...@i.am | Ian Stirling.
---------------------------+-------------------------+--------------------------
Acting is merely the art of stopping a large number of people from coughing
- Sir Ralph Richardson
yoleus
"Ian Stirling" <ro...@mauve.demon.co.uk> wrote in message
news:1022864882.7843.0...@news.demon.co.uk...
> In sci.electronics.misc yoleus <yoleus@hotmailspam_me_not.com> wrote:
> >
> >
> > "Scott MacLean" <sco...@spamnerosoft.com> wrote in message
> > news:a48J8.7749$t97.1...@news20.bellglobal.com...
> >> Yup. My Braun shaver takes from 12V to 240V, AC or DC, any polarity,
and
> >> figures it out for itself what to do with it.
> >
> > What a stunningly original idea !
> <snip>>
> > For most low power devices, you could just overrate a 78XX regulator and
> > drop twice the power when running off a 240v supply. For anything with
a
> > switching mode power supply it should be just as easy.
>
> For a linear PSU, you'd increase the size.
> Need a higher voltage cap (with same ESR), and about double the size of
> transformer.
> For real low-power, this wouldn't matter of course.
>
That was what I was trying to say really. For low power, just use a bigger
regulator and for higher power, a switching mode supply should be able to
deal with a factor of two change in input voltage. Given that people are so
much more mobile these days, I am surprised there has not been more
commercial pressure on manufacturers to make their equipment dual voltage.
I know I would pay 10% -20% more for a device that would work anywhere.
Alan Gottschald
however I have had to replace the batteries and noted that it has a
very simple circuit, it does have a bridge a few cap's and an
ecapsulated device which I deduce to have a constant current circuit
with a voltage monitor to cut the charging when the charge is "full".
It does indeed work on all the stated voltages, for such an old design
you would think every maker of portable devices would have used
something like it.
You know it's not just a myth the Germans have some really good
engineers. When you think in fifteen years, only to have the nicad
batteries replaced once and that was after ten years service, is very
good.
Of course they've not sold me a thing since I bought it, even the foil
is still as sharp. I guess good engineering does not equal good
business, at least in the short term but when it does eventually die
as all things must, I will look first to Braun for a similar device
and god help them if it's not as reliable as this one...
Alan.
Daniel <d...@joey.tanj.com> wrote:
>In alt.energy.homepower Scott MacLean <sco...@spamnerosoft.com> wrote:
>> Yup. My Braun shaver takes from 12V to 240V, AC or DC, any polarity, and
>> figures it out for itself what to do with it.
>>
>> "DaveC" <an...@me.invalid> wrote in message
>> news:01HW.B91A48890...@news.dnai.com...
>>> From: DaveC <an...@me.invalid>
>>> Newsgroups: sci.electronics.repair
>>>
>>> The Braun rechargable shaver I bought comes with a detachable 120VAC cord.
>>> The instructions say that a 12VDC automotive cord is available for the car
>>> cigarette lighter.
>>>
>>> I presume that the automotive cord doesn't convert 12VDC to 120VAC, but
>> that
>
>I use the 7570 with the cleaning station. The unwieldly AC plug actually
>contains a voltage converter. It puts out 12V DC at 400 ma. The shaver
>itself does not handle the various voltages.
>
>My other Braun has a built in charger. It will take multiple voltages.
>I'm pretty sure that they use rectifier bridge to get the right polarity
>to the right spots.
==============================================
Englishman in New York....
B. W. Salt.
Take care! Not all Braun equipment is of good quality. My Braun shaver was a terrible piece of 'engineering', with the charging
connections being two pins locating in clips on the PCB. Constant no-charge and no-run on mains, until I took it to pieces and
replaced the contacts with flexible wire from the connector pins to the board.
Eventually chucked it away. Turned me off Braun completely.
Blippo
"Alan Gottschald" <NoS...@here.all> wrote in message
news:3d24e7d1....@news.citlink.net...
> I've had my Braun since 1987, and it has worked with little trouble,
> however I have had to replace the batteries and noted that it has a
> very simple circuit, it does have a bridge a few cap's and an
> ecapsulated device which I deduce to have a constant current circuit
> with a voltage monitor to cut the charging when the charge is "full".
>
> It does indeed work on all the stated voltages, for such an old design
> you would think every maker of portable devices would have used
> something like it.
>
> You know it's not just a myth the Germans have some really good
> engineers. When you think in fifteen years, only to have the nicad
> batteries replaced once and that was after ten years service, is very
> good.
>
> Of course they've not sold me a thing since I bought it, even the foil
> is still as sharp. I guess good engineering does not equal good
> business, at least in the short term but when it does eventually die
> as all things must, I will look first to Braun for a similar device
> and god help them if it's not as reliable as this one...
>
> Alan.
>
I bought a Braun Flex Integral at the weekend. It seems they have now
addressed this lack of 'built-in obsolescence'. Braun have cunningly
designed the housing so that if you open it, the shaver is destroyed. No
chance of home repairs or replacing the cells.
They even have the gall to claim that this feature is to facilitate easy
disassembly at the end of its life 'for recycling purposes'. My old Braun
housing was held together by a single screw - hardly a major obstacle to
someone keen to save the earth's resources.
Michael A. Terrell
So you're saying that by removing the screw... you're screwed?
Lee Blaver
> I bought a Braun Flex Integral at the weekend. It seems they have now
> addressed this lack of 'built-in obsolescence'. Braun have cunningly
> designed the housing so that if you open it, the shaver is destroyed. No
> chance of home repairs or replacing the cells.
>
> They even have the gall to claim that this feature is to facilitate easy
> disassembly at the end of its life 'for recycling purposes'. My old Braun
> housing was held together by a single screw - hardly a major obstacle to
> someone keen to save the earth's resources.
In the UK the Braun integral's have this "screw", but they still have the
hidden screws
which allow it to be dismantled -- they are well-hidden under the caps though
:-)
Lee