Re: Connect one model's AC adapter to other model?

Re: "I don't have a whole lot of visibility into the intelligence/sophistication that is engineered into the whole Adapter/
Recharger/Calibration/PowerSupply system."

Well, I do. And for the most part, they are relatively unsophisticated, fairly simple systems. The power adapter is usually just a DC power source that is an INPUT to a switching power supply in the laptop, and switching power supplies are, in general, unbelievably tolerant of extremely wide variations in their input, as long as enough total power is present (and if it's not, they usually just shut down). Dell and a few others have recently complicated things by sending data over the power lines that allows the laptop to identify a "genuine" power supply and refuse to work with a power supply not made by the laptop manufacturer.

[I am a degreed electrical engineer who has worked for both power supply and laptop manufacturers. I have been in the computer industry for decades, I am A+ and Network+ certified and I am also a Microsoft Certified Professional and I buy, service, rebuild and resell laptops.]


dubiousdude@xxxxxxxxx wrote:
On Dec 26, 1:52 pm, Barry Watzman <WatzmanNOS...@xxxxxxxxxx> wrote:
dubiousd...@xxxxxxxxx wrote:
Hmm. My reason for the original post in this thread was to put
feelers out on the level of confidence that the laptop won't be
damaged, based on the response of more experienced tech people (vetted
through the filters of my finite experience on usenet, which suggests
high caution). My assessmment (which aligns with what I've heard
here) is that the risk is high.
The risk of damage is LOW ***IF***:

-The voltages are the same or very close (within 5%)
-The power connector is a simple 2-wire connector of the same size
-The polarity is the same

If the capacity of the "substitute" adapter is more than about 20% below
the capacity of the "right" adapter, there is a SLIGHT risk of
overheating (and, in an extreme case, damaging) the substitute adapter.
The risk is not great but it increases with the undercapacity. This a
much lower risk that the laptop won't run or won't run reliably or will
be damaged. These risks increase with increasing undercapacity of the
substitute adapters, but I often use laptops that came with 5 amp
adapters with 4 (and sometimes even 3) amp adapters with no problems.
If the undercapacity worries you, use the substitute adapter only to
charge the battery (but not run the laptop).

If the adapter has a connector other than a 2-wire plug of the same
polarity, if the voltage is different (more than 5%) or if the current
undercapacity (amps) is great, then the risk is high.

Overcapacity is not an issue at all; you could use a 15 volt 6 amp
supply on a laptop that specified an otherwise compatible 15 volt 2 amp
supply with no problems whatsoever.

Thanks, Barry. At this point, I think I'll still hold off. The
uncertainty and unknowns seen from my vantage points go beyond raw
capacity. I don't have a whole lot of visibility into the
intelligence/sophistication that is engineered into the whole Adapter/
Recharger/Calibration/PowerSupply system. Could be that there is not
much to worry about with regard to these aspects, but it seems
appropriate to refrain from forging ahead in the absence of evidence
for that (from the vantage point of the common user).
** Posted from http://www.teranews.com **
.

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