[ltp] Thinkpad power adapters and less than 100V mains

[Jason Brooks]

I think they should send the best. It is the cheapest thing in the
whole rig usually. But it is my opinion. My advice: Get a good supply
with a high amp rating. For unstable power situations get a UPS they
are designed for brownouts which are low current issues.

On Mon, Oct 17, 2011 at 7:30 AM, Richard Neill <rn214@richardneill.org> wro=
te:
>> Does it damage a Thinkpad power adapter to use the laptop plugged in
>> when the electricity supply is potentially less than 100V?
>
> Personally, I think you're unlikely to damage the supply, but may force i=
t
> into thermal shutdown; you may wish to try to reduce your laptop's curren=
t
> draw at this point.
>
> IBM used to make AC/DC supplies that could run off either a 110/240V AC
> line or off a 12 cigarette-lighter socket. You can still get these on eBa=
y;
> I'd imagine that internal electronics of these is rather more over-specce=
d.
>
> Best wishes,
>
> Richard
>
>
> BTW, I wouldn't necessarily blame the manufacturers for shipping
> lower-wattage supplies: as the machines get more energy-efficient, they j=
ust
> need less power, and a lower-wattage supply weighs less.
>
>
>
>
> On 17/10/11 03:25, Jason Brooks wrote:
>>
>> Since the power coming out of the supply will be regulated it
>> shouldn't hurt the laptop.
>> You could cause problems for the power supply because it will be
>> working harder. The constant charge and surge that the capacitors will
>> go through in a low power situation would shorten the life of them.
>> Normally this wouldn't be a issue since they charge and stay charged
>> in a full power situation. =C2=A0Is this why your power supply is acting
>> flaky? Maybe but more than likely it is from every day use. All
>> manufactures are cutting back and bundling the lowest wattage power
>> supply they can. They don't last. I had a HP power supply that was 90W
>> for about a year... then it was 70 watt... =C2=A0Replaced it with a APC
>> power supply and have not had a problem since. I would suggest the
>> same to you.
>>
>> On Sun, Oct 16, 2011 at 6:54 PM, Damon Lynch<damonlynch@gmail.com> =C2=
=A0wrote:
>>>
>>> Hi everyone,
>>>
>>> Does it damage a Thinkpad power adapter to use the laptop plugged in wh=
en
>>> the electricity supply is potentially less than 100V?
>>>
>>> This past summer I used my T400s in such a situation. The laptop was
>>> sometimes doing computationally intensive work. The power supply became
>>> quite a bit hotter than it normally does. In fact sometimes it was very
>>> hot
>>> indeed. I don't know if this damaged it or not. All I do know is that
>>> when I
>>> now use my T400s for computationally intensive work for extended period=
s,
>>> if
>>> I use that same power supply, the laptop can shut down without warning.
>>> If I
>>> use another power adapter (which I did not use in that kind of low
>>> voltage
>>> situation), it never shuts down.
>>>
>>> Perhaps the answer is "Why yes of course, you have damaged the power
>>> supply.
>>> Never run on less than 100V." However I believe the power adapter simpl=
y
>>> might be a bit dodgy, as the laptop would occasionally shut down withou=
t
>>> warning even before I used it when the mains was less than 100V . It
>>> didn't
>>> do it a lot, but it did sometimes. The only difference is that it does =
it
>>> far more regularly now.
>>>
>>> A related question: if I am in a situation where the mains supply is le=
ss
>>> than 100V and I'm running the laptop off it with the battery present
>>> (which
>>> might be charging), does it make any difference if I am using lower pow=
er
>>> Thinkpad like a T400s as compared to say a W520? Furthermore, if using
>>> the
>>> laptop when the laptop is powered on actually is bad, is it still
>>> perfectly
>>> ok to charge the laptop battery from a low-voltage mains when the lapto=
p
>>> is
>>> off?
>>>
>>> As you might guess, I'm far from expert in these matters so if the
>>> answers
>>> to my questions are blindingly obvious then I apologize :)
>>>
>>> Thanks,
>>> Damon
>>> --
>>> http://www.damonlynch.net
>>>
>>
>>
>>
> --
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> http://mailman.linux-thinkpad.org/mailman/listinfo/linux-thinkpad
>



--=20
JaY