T60P using a 65W AC Adapter

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RiverFly · #1 Post by **RiverFly** » Fri Dec 01, 2006 6:37 am

I had a question posed to me that I did not know the answer. On a T60P, the end user claimed that using a 90W adapter on airlines tends to trip the seats power circuit on the plan (I never heard of this before) and they wanted to know if they could use a 65W adapter. I have used lower w A/C adapters on the T43P and I got a lot of screen flickering. Does anyone know if this will hurt the system?

JonathanGennick · #2 Post by **JonathanGennick** » Fri Dec 01, 2006 7:58 am

Using a lower wattage adaptor strikes me as similar to putting the proverbial penny in the fusebox. Assuming the voltage delivered is correct, then the lower wattage means that the laptop will be trying to draw more amps than the adaptor can safely deliver. Either the laptop won't get enough current, or the adaptor will pass too much current.

I'm not sure about damage from not getting enough current. My guess is that not enough current would lead to the sort of erratic behavior that you already see (your flickering screen). Or maybe the laptop would not work at all.

If the adaptor somehow were to pass more current than it was designed for, well, then you have a fire hazard from overheating.

Speaking for myself, I would not take the risk of using an under-spec'd power supply.

dfumento · #3 Post by **dfumento** » Fri Dec 01, 2006 8:10 am

I'd just be certain to use the standard IBM/Lenovo airplane adapter. IBM/Lenovo is very careful about testing things out and I'm certain that it will work correctly.

#4 Post by **RonS** » Fri Dec 01, 2006 12:08 pm

I would advise the end user to minimize the Thinkpad's power use. Don't play 3D graphics games or run CPU-intensive applications. Just run Office-like apps with maybe the screen dimmed a bit, and turn the radios off.

Power usage should be around 20W or less (see the Power Manager). Your user may even want to set up a Power Scheme for airline use.

ldoogy · #5 Post by **ldoogy** » Mon Dec 04, 2006 9:44 am

I had a similar experience with the 90W adapter on a flight (with a T60p). The plane was a Lufthansa 747 with 110V US power plugs, and the jack had a green LED and a red LED. When I plugged the adapter in the green LED was on, but a short while after starting the T60p, the LED turned red, and the computer beeped, indicating that it's running on batteries. Essentially there was a power overload, and the jack has some safety mechanism built into it that shuts it down automatically.

I had initially thought my specific seat jack was defective, but others presented the exact same behaviour! Was does this mean? Are these T60p's too power hungry for the seat power sockets??

#6 Post by **tomh009** » Mon Dec 04, 2006 10:09 am

ldoogy wrote:I had a similar experience with the 90W adapter on a flight (with a T60p). The plane was a Lufthansa 747 with 110V US power plugs, and the jack had a green LED and a red LED. When I plugged the adapter in the green LED was on, but a short while after starting the T60p, the LED turned red, and the computer beeped, indicating that it's running on batteries. Essentially there was a power overload, and the jack has some safety mechanism built into it that shuts it down automatically.

One workaround is to remove the battery -- that way the T60 won't be drawing power for operation and for charging the battery at the same time. Or charge the battery first before turning the T60 on ...

Rovers3 · #7 Post by **Rovers3** » Mon Dec 04, 2006 12:14 pm

Could be the Airlines power outlets are not set for a 90W power adapter.

I have been using a 65W power adaptor from day 1 and never had a problem yet, i use the Lenovo adapter made for the T60p

On the airplane, i use a 75W converter and still no problems. The AutoAir adapter might be better suited for you if you travel alot.

nausherali · #8 Post by **nausherali** » Tue Dec 05, 2006 12:20 am

I had the same issue on an Air France flight. The socket was rated at 70w, and it was able to charge up the battery but turned off when I booted up the laptop.

awallin · #9 Post by **awallin** » Tue Dec 05, 2006 10:07 am

JonathanGennick wrote: Speaking for myself, I would not take the risk of using an under-spec'd power supply.

I would imagine that power manager shows the actual wattage used which is about 25 W maximum.

So the only effect of using a lower power adaptor would be that the battery is charged at a slower rate ?

If you want to push it a small travel adaptor could be rated at 25 or 30W but charging(while the machine is on) would not be very quick...

Then there are the intricacies of charging LiPo cells, but if I recall correclty using a smaller than rated current should not be a problem ?

AW

T60P using a 65W AC Adapter

T60P using a 65W AC Adapter

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