Instructables

Please explain HP SMART tip AC power supply replacements to me?

I have an HP 2133 Mini-note netbook computer that uses a 65 Watt AC adapter (18.5V 3.5A) AC adapter. The plug/socket arrangement that plugs into the computer is the large barreled/micro-pin style of plug that mirrors the SMART plug style used natively on the Accessory adapters that HP sells for a very Prince-ly sum.
My Accessory adapter is rated 90 watts. It will "SMART" itself to the proper output Voltage to operate my laptop, BUT, I am concerned that the 90 Watt vs. 65 Watt  difference in the marked ratings will foul up my Mini-Note somehow or other.
The Accessory AC Adapter (part #:463553-002)  has not been listed as suitable for my application, although it does have some other machines listed on it's suitability chart that overlap with my model.
HP support is of no help what-so-ever, they will only suggest that I spend MORE on another adapter, rather than help me to understand thier offerings.
Please help me to puzzle this out, rather than spend more....and more.... 

Re-design4 years ago
I also have an HP laptop.  I keep the original charger at home and a Belkin "smart" charger at the office.  I too was worried about using an non HP charger, but after at least 18 months of plugging in to it twice a week I have found no detrimental effects.

When I first plugged it in I was a little apprehensive and watched closely for any unexpected smoke, visible flames or reforming plastic panels but found nothing.
kelseymh4 years ago
I didn't find much "theory of operation" stuff on the Web, just resellers and HP's basic spec sheets. 

A good general statement is that power adapters do not "push" current -- they let current be "pulled" by whatever they are plugged into.  The power rating (65W or 90W or whatever) tells you the maximum power that the wall-wart can handle.  If you plug it into a device that tries to use more than that, the wall-wart will overheat and either blow a fuse or start a fire :-/

Without any other information, I would assume that you can plug a 90W adapter into a device which only needs 65W, but not the other way around.