Car adaptor underpowering T22?

[Nolonemo]

I have a model E302 PowerXtender car/plane adaptor that apparently was designed for the 560 and 365 series. It indicates that its output is 16v 2.2A. The power specs on the bottom of my T22 say 16v 3.36A.

Can I harm the T22 by running it off of this adaptor?

Thanks.

[jkirch]

Hi,

I believe your T22 came with a 72W Power adapter where as your 560 only came with a 35W (560 /E) or 56W (560Z/X) AC adapter.
The T22 requires about 54 W (16V*3.36A) of power input to run.

This is because the T22 uses more power than the 560.

The E302 PowerXtender can output 35W (16V*2.2A) which is sufficient for the 560 (not560X/Z) to power the and charge the battery, but it might not be enought to power the T22 and also charge the battery.

High load on the power adapter might cause it to fail.

For save opereation it is probably better to get a higher rated adapter.

Hope I could help.

Jens

[GG-OnE]

Try it. You won't harm your T22 imho, but if it gets not enough power it won't run stable. So, if it crashes, your PowerXtender is definitely too weak...

[Nolonemo]

Thanks, GG & Jkirch.

I also did a little searching on notebookforums.com, and someone there said that if the adaptor was not putting out enough current for the TP, the battery would kick in to make up the difference. So I'll do a little test today, when I'm out in the car (have a 40 min or so drive to make), play a DVD, which is about the most power-intensive operation I'd be doing on the adaptor, and see if the battery charge level goes up or down.

[Nolonemo]

Some followup testing:

Playing a DVD with the computer on the car adapter. Play time was 55 min., at the start, the battery charge was 32%, at the end of the 55 minutes, it had dropped to 30%, for a chage loss conservatively estimated at 3%.

Therefore I assume that the charger was not supplying enough current and the battery was taking up the slack. Assuming a loss of 3% per hour, after 5 hours (cross-country flight) on the charger, I would have lost 15% of the batter charge, which is OK (assuming I had a good charge to start).

I also tried an older and physically smaller adapter I had. This time, the DVD played 70 minutes, and the battery charge went from 44% to 50%, for a charge gain conservatively estimated at 5%. Thus, this adapter appears to provide more than sufficient current to power the thinkpad by itself. However, the adapter ran so hot that you could barely hold it. This leads me to think that this adaptor wouldn't last very long with repeated use.

Moral: use stuff that spec'd for the stuff you're using it with.