[ltp] Re: Slightly off-topic: different wattage

[Helen Borrie]

At 11:54 PM 21/09/2009, you wrote:
>Axel Braun wrote:
>> James Knott wrote:
>>
>>   
>>>> The 90 W / 20 V AC adapter that came with my T60 recently broke - what
>>>> are the drawbacks of using a 65 W / 20 V one instead (we have a spare
>>>> one of those at work)? Is charging going to take substantially longer?
>>>>
>>>>       
>>> A 90W adapter was provided because it was expected it's capacity would
>>> be needed.  A 65W adapter would not be sufficient.
>>>     
>>
>> Well...my Z60m was delivered with a 90W adapter, but for travel purposes I 
>> have a 65W adapter as well. It gets slightly hotter, but does the job.
>>   
>When a company designs hardware, they have to allow for extremes
>conditions and to provide a bit of a margin.  While that 65W adapter may
>work most of the time, there may still be problems.  For example, with
>that adapter running hotter, you've increased the risk of component
>failure.  There is a reason for the increase in adapter ratings a few
>years back and you can be sure it wasn't the companies being generous.

The T60 parts list lists both.  My T60 came with a 65W adapter and I bought a spare 90W one for when I'm studying in bed.  The supplied 65W adapter doesn't get hotter than the 90W one, even though my daytime usage load involves a lot more activity.  I'd swap them round if I had evidence that the difference mattered. 

AC adapters 
FRU P/N RoHS ID CRU ID 
2-pin (90 W, 20 V) adapter (models CTO, xxE, xxF, xxJ, xxL, xxP, xxS, xxY, xxU) ASTEC 42T5000 R * Lite-On 93P5026 R * Sanken 92P1114 R * 
2-pin (65 W, 20 V) adapter (models CTO, xxE, xxF, xxJ, xxL, xxP, xxS, xxY, xxU) Delta 92P1155 R * Lite-On 92P1159 R *
3-pin (90 W, 20 V) adapter (models CTO, xxA, xxB, xxC, xxG, xxH, xxK, xxM, xxT, xxV) OP ASTEC 92P1104 R * Lite-On 92P1108 R * Sanken 92P1112 R * 
3-pin (65W, 20 V) adapter (models CTO, xxA, xxB, xxC, xxG, xxH, xxK, xxM, xxT, xxV) OP Delta 92P1153 R * Lite-On 92P1157 R * 

(f.w.i.w)
Helen