Power Transformer

My cousin came to USA from asia to visit last week with his Dell Laptop (used 220 watt). He plugged the adaptor to charge battery but no power. The adaptor clearly read 110 - 220 input, so it was assume it will auto transformer 110 watt to 220 watt to work.

Luckily he have a power transformer with him. And sure enough, it work when it plugged to the transformer and notebook power on.

I don't know why the ac adaptor don't work when it was a built in transformer.

So my question is this, I have a Dell 1720 notebook with ac adaptor read 110 - 220 watt input as well.

If I go to asia or where they country use 220 watt, Must I buy as power transformer to bring down 220 to 110 watt and plugged in my adaptor?

 

its volts, not watts.......i thinik in some countries, the physical plug is different. a good electronics store should have adapters for those.

as to why the adapter didn't work..............i'm not too sure.

 

Hes wasnt plugging it in correctly. lol. All laptop adapters work on 220 volts.

 

Thanks. I understand about the different type of plugs.

What I want to know is, if I should spend money to buy a transformer?
Because Dell told me the ac adaptor is auto transform power and should work if I bring it to another country that have 220 volts.

Instead of guessing, maybe I should buy a transformer to prevent my laptop from burning out.

 

no, some are designed to work just on 110, or just on 220-240V. but if it says 110-220, you would like to think that it was human error.

 

It should. I went to HK and Japan 3 years ago with my 7 years old Toshiba Satellite and the ac adapter worked perfectly. As long as you plug it into the right socket a new dell ac adapter should work equally as well.