I'll be going away on holiday to somewhere that has continental-type
mains sockets with two round pins. I have a suitable adapter plug thingy
that provides two USB outlets, one rated at 5 volts and the other at 1
volt. My smartphone spec says that it has a 3.7 volt battery. Would I
risk damaging the battery if I used the 5v outlet? If I can't safely use
the 5v outlet, will the 1v outlet actually be able to charge the
battery? (If so, I assume it will take a rather long time to do so.)

TIA.
--
John Hall
"Home is heaven and orgies are vile,
But you *need* an orgy, once in a while."
Ogden Nash (1902-1971)

In message <owYun6AKRLhiFws2@jhall_nospamxx.co.uk>, John Hall
<john_nospam@jhall.co.uk> writes
>I'll be going away on holiday to somewhere that has continental-type
>mains sockets with two round pins. I have a suitable adapter plug
>thingy that provides two USB outlets, one rated at 5 volts and the
>other at 1 volt. My smartphone spec says that it has a 3.7 volt
>battery. Would I risk damaging the battery if I used the 5v outlet? If
>I can't safely use the 5v outlet, will the 1v outlet actually be able
>to charge the battery? (If so, I assume it will take a rather long time
>to do so.)
>
>TIA.

Oops! My apologies. I don't know where I got the 5v and 1v from. The
outlets are actually labelled 2.1A and 1A. So which of those should I
use?
--
John Hall
"Home is heaven and orgies are vile,
But you *need* an orgy, once in a while."
Ogden Nash (1902-1971)

On 18/05/2022 10:06, John Hall wrote:

> The outlets are
> actually labelled 2.1A and 1A. So which of those should I use?

Either will work without harming the phone, but the 2.1A ought to do the job faster.

On 18/05/2022 10:06, John Hall wrote:
> Oops! My apologies. I don't know where I got the 5v and 1v from. The
> outlets are actually labelled 2.1A and 1A. So which of those should I
> use?

And with any charger, never leave it unattended.

You see lots from the greenies about chargers costing a few pence a year
when left running all the time but there is a fire danger from anything
like that is left unattended,

On 18/05/2022 10:31, Andy Burns wrote:
> Either will work without harming the phone, but the 2.1A ought to do the
> job faster.

That depends on whether the phone supports the way that the chargers
signals its capabilities. If it doesn't it should fall back to a slow
charge. (It's actually the charger that is at risk, if it gets this
wrong, not the phone.)

On 18/05/2022 13:40, MB wrote:
> On 18/05/2022 10:06, John Hall wrote:
>> Oops! My apologies. I don't know where I got the 5v and 1v from. The
>> outlets are actually labelled 2.1A and 1A. So which of those should I
>> use?
>
>
> And with any charger, never leave it unattended.
>
> You see lots from the greenies about chargers costing a few pence a
> year when left running all the time but there is a fire danger from
> anything like that is left unattended,

What's the actual real life risk, compared with (for instance), the
control board in your boiler, the clock on your oven, your PVR in
standby, your masthead amp PSU, your bedside clock-radio, or even your
mains powered smoke alarm ?

On 18/05/2022 15:20, Mark Carver wrote:
> What's the actual real life risk, compared with (for instance), the
> control board in your boiler, the clock on your oven, your PVR in
> standby, your masthead amp PSU, your bedside clock-radio, or even your
> mains powered smoke alarm ?

It is usually the cheap and nasty wallwarts that are the cause and not
all those use one but you regularly see reports of fires caused by a
phone on charge.

Just seems a simple precaution to not leave a cheap charger, costing
pennies and not made or supplied by the phone manufacturer, charging
unattended. Quite likely does not do the batteries any good either
(however clever they claim the charger is).

On 18/05/2022 16:13, MB wrote:
> On 18/05/2022 15:20, Mark Carver wrote:
>> What's the actual real life risk, compared with (for instance), the
>> control board in your boiler, the clock on your oven, your PVR in
>> standby, your masthead amp PSU, your bedside clock-radio, or even your
>> mains powered smoke alarm ?
>
> It is usually the cheap and nasty wallwarts that are the cause and not
> all those use one but you regularly see reports of fires caused by a
> phone on charge.
>
> Just seems a simple precaution to not leave a cheap charger, costing
> pennies and not made or supplied by the phone manufacturer, charging
> unattended. Quite likely does not do the batteries any good either
> (however clever they claim the charger is).
>
>

Indeed, but you've moved the goal posts slightly.
I don't think a 'well known manufacturer's' phone charger, left plugged
in but not charging poses any significant risk  ?  The risk increases
when it's charging, though I suspect if anything is going to burst into
flames it'll be the phone battery, rather than the charger. I do worry
about phones and laptops getting charged onboard planes (I do it myself
though)

In message <jejso1Fp38mU1@mid.individual.net>, Andy Burns
<usenet@andyburns.uk> writes
>On 18/05/2022 10:06, John Hall wrote:
>
>> The outlets are actually labelled 2.1A and 1A. So which of those
>>should I use?
>
>Either will work without harming the phone, but the 2.1A ought to do
>the job faster.
>

Thanks.
--
John Hall
"Home is heaven and orgies are vile,
But you *need* an orgy, once in a while."
Ogden Nash (1902-1971)

In message <t62pfr$dn9$1@dont-email.me>, MB <MB@nospam.net> writes
>On 18/05/2022 10:06, John Hall wrote:
>> Oops! My apologies. I don't know where I got the 5v and 1v from. The
>> outlets are actually labelled 2.1A and 1A. So which of those should I
>> use?
>
>
>And with any charger, never leave it unattended.
>
>You see lots from the greenies about chargers costing a few pence a
>year when left running all the time but there is a fire danger from
>anything like that is left unattended,

I'm from the generation that doesn't leave anything electrical switched
on unnecessarily.
--
John Hall
"Home is heaven and orgies are vile,
But you *need* an orgy, once in a while."
Ogden Nash (1902-1971)

In article <t632ei$leq$1@dont-email.me>,
MB <MB@nospam.net> wrote:
> On 18/05/2022 15:20, Mark Carver wrote:
> > What's the actual real life risk, compared with (for instance), the
> > control board in your boiler, the clock on your oven, your PVR in
> > standby, your masthead amp PSU, your bedside clock-radio, or even your
> > mains powered smoke alarm ?

> It is usually the cheap and nasty wallwarts that are the cause and not
> all those use one but you regularly see reports of fires caused by a
> phone on charge.

been turfed out of a hotel at about 4 in the morning ( very frosty morning,
too) because one of those caught fire.

> Just seems a simple precaution to not leave a cheap charger, costing
> pennies and not made or supplied by the phone manufacturer, charging
> unattended. Quite likely does not do the batteries any good either
> (however clever they claim the charger is).

--
from KT24 in Surrey, England
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

John Hall <john_nospam@jhall.co.uk> wrote:
> I'll be going away on holiday to somewhere that has continental-type
> mains sockets with two round pins. I have a suitable adapter plug thingy
> that provides two USB outlets, one rated at 5 volts and the other at 1
> volt. My smartphone spec says that it has a 3.7 volt battery. Would I
> risk damaging the battery if I used the 5v outlet? If I can't safely use
> the 5v outlet, will the 1v outlet actually be able to charge the
> battery? (If so, I assume it will take a rather long time to do so.)
>
I think you are a little confused.

*All* USB outlets should provide 5 volts and have a minimum current
capability of 500mA. Your phone is expecting to get 5 volts. It has
electronic circuitry that charges the 3.7 volt battery from the 5 volt
supply.

I know of no USB 'outlet' that provides only 1 volt, I think you must
be misreading something. On twin outlets like you seem to have it's
quite common for one to be able to provide (up to) 2.1 amps and the
other (up to) 1 amp. Is that where you're getting the '1' from maybe.
Anyway, both outlets will be 5 volts and the 2.1 amp one *may* charge
your phone a bit more quickly than the 1 amp one, it depends on how
the phone and the 'charger' interact.

--
Chris Green
·

In message <0tpfli-h2l1.ln1@esprimo.zbmc.eu>, Chris Green <cl@isbd.net>
writes
>John Hall <john_nospam@jhall.co.uk> wrote:
>> I'll be going away on holiday to somewhere that has continental-type
>> mains sockets with two round pins. I have a suitable adapter plug thingy
>> that provides two USB outlets, one rated at 5 volts and the other at 1
>> volt. My smartphone spec says that it has a 3.7 volt battery. Would I
>> risk damaging the battery if I used the 5v outlet? If I can't safely use
>> the 5v outlet, will the 1v outlet actually be able to charge the
>> battery? (If so, I assume it will take a rather long time to do so.)
>>
>I think you are a little confused.
>
>*All* USB outlets should provide 5 volts and have a minimum current
>capability of 500mA. Your phone is expecting to get 5 volts. It has
>electronic circuitry that charges the 3.7 volt battery from the 5 volt
>supply.
>
>I know of no USB 'outlet' that provides only 1 volt, I think you must
>be misreading something. On twin outlets like you seem to have it's
>quite common for one to be able to provide (up to) 2.1 amps and the
>other (up to) 1 amp. Is that where you're getting the '1' from maybe.
>Anyway, both outlets will be 5 volts and the 2.1 amp one *may* charge
>your phone a bit more quickly than the 1 amp one, it depends on how
>the phone and the 'charger' interact.
>

Thanks. I corrected myself in a follow-up post. I've no idea what made
me think the outlets were 5v and 1v.

Some subsequent research on the web suggested that the 2.1 amp outlet is
intended for tablets and the 1 amp for mobile phones. Some people also
seemed to think that using the 2.1 amp one with a mobile phone could
risk damage.
--
John Hall
"Home is heaven and orgies are vile,
But you *need* an orgy, once in a while."
Ogden Nash (1902-1971)

On 18/05/2022 18:52, charles wrote:
>
> been turfed out of a hotel at about 4 in the morning ( very frosty morning,
> too) because one of those caught fire.

Well, at least that was a *real* emergency ...

www.macfh.co.uk/Macfarlane/Reminiscences/Livermudlian.html

--

Fake news kills!

I may be contacted via the contact address given on my website:
www.macfh.co.uk

On 18/05/2022 16:45, John Hall wrote:
> I'm from the generation that doesn't leave anything electrical switched
> on unnecessarily.

Ditto!

Anything that does need to be left switched on will be fed through a RCD
just to give a bit of protection.

On 18/05/2022 23:07, MB wrote:
> Anything that does need to be left switched on will be fed through a RCD
> just to give a bit of protection.

RCDs don't protect against live to neutral shorts.