Hot AC adaptor

[fozzy40]

I have been noticing that my AC adapter (original) has been hotter than usual after being plugged into both the wall and laptop. It does cool off even when plugged into the wall and not the laptop. Should I be concerned?

fozzy40

[jdhurst]

It is normal for that to happen (no laptop current means very low adapter current). In normal use, the adapter will get very warm, but not burning hot. My adapter in the desk cupboard (where the tower sits running all the time) has about a 95 degree F surface temperature, which seems reasonable. ... JDH

[richk]

I agree with the previous response, but make sure you have the right adapter. You need one that can put put 4.5 amps. A smaller adapter will overload and get hot.

[rbena]

I have three AC adapters, all rated at 4.5A, for for my T42 laptops. Two adapters run at normal temperature, and one runs hot. So something causes an adapter to run hot.

[frankiepankie]

I have 2 adapters.

One which was supplied with my T40, 16V 4.5A
One which was supplied with my dad's ex-T30, 16V 4.5A

The one from the T30 is getting hot during usage, but the other one isn't :S

They are really both 16V 4.5A

[rbena]

If someone really wanted to find the answer, they could simply disassemble and compare the two adapters. Anyone?
My guess is it's either the transformer which is deteriorating, or a faulty component making the unit run less efficient and generating additional heat.

[Troels]

Numerous manufacturers produce and produced the power adaptors. As long as it follows the requirements from Lenovo, they could use whatever topology they want, and there probably are some variations, and the efficiency has likely improved a bit over the years. Maybe the effiency requirements, weight, etc. has also changed during the years, even though it is still 16V up to 4.5A

[rbena]

Numerous manufacturers produce and produced the power adaptors.

I was also going to mention variations in components, but was assuming a certain standard was being adhered to. I suppose that could also account for the variation in temperature - but not a nice thought.

[AIX]

I noticed that my last AC adapter (acquired recently) (92P1017) runs a little bit colder than my previously 08K8207 adapter; 92P1017 is a two-prong, made for Lenovo, 08K8207 is a three-prong, made for IBM (4 year old now).

[rbena]

Thought you might be onto something - but of the three 4.5A adapters I have, a 3-prong runs hot, the other 3-prong runs cool, and a 2-prong runs cool.

Perhaps the serial numbers or something identifying the manufacturing details -may- be relevant. But I suspect there is deterioration also occuring, causing some adapters to gradually run hotter.

I simply use the hotter one for less critical and shorter duty use. They're a relatively inexpensive item, so if one runs hot or fails, it's no drama to replace it.