AC Adapter for Laptop

Len Lanetti

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Lenny
Hello,

For work the company has provided me with a new laptop. In a cost cutting measure they did not provide me with a second power adapter. This would mean each night I would have to unplug the AC adapter from the dock and take it home or along on a business trip as opposed to keeping the second adapter in my computer bag.

What I would like to know is can I use the similar spare AC power adapter from my previous laptop. From what I can tell the differences in the adapter is in the input power. The new adapter is marked as drawing "~1.9A". The old adapter is marked as drawing "~1.5A-0.9A". Both the old and new adapter are marked as having output of "16V 4.5A".

I'm thinking that because the output is the same it should be ok to use the old adapter with the new computer.

Comments?

Thanks,

Len
 
Len Lanetti said:
Hello,

For work the company has provided me with a new laptop. In a cost cutting measure they did not provide me with a second power adapter. This would mean each night I would have to unplug the AC adapter from the dock and take it home or along on a business trip as opposed to keeping the second adapter in my computer bag.

What I would like to know is can I use the similar spare AC power adapter from my previous laptop. From what I can tell the differences in the adapter is in the input power. The new adapter is marked as drawing "~1.9A". The old adapter is marked as drawing "~1.5A-0.9A". Both the old and new adapter are marked as having output of "16V 4.5A".

I'm thinking that because the output is the same it should be ok to use the old adapter with the new computer.

Comments?

Thanks,

Len
Should be fine. You are going to want to check the polarity of the plug. It would really ruin your day if one of the adapters were reversed.

That said, I wouldn't hesitate to try it after I checked that. Of course if the sparks start flying...I blame Tony Condon.
 
ah jeez, im going to be famous after much more of this...
 
FlyNE said:
Are the computers the same brand?
Ditto this. If they're the same brand, you're fine provided the numbers match. If amperage (A) is higher on the older power supply but the voltages match, you're still fine. The battery will draw what it needs so A needs to be close or over. You're actually STILL okay with a lower A but it takes longer to charge and you may go into a deficit with the battery while using it.

Voltages need to match, though. Too much can hurt the battery and too little will not charge it.

Like Jesse said, check the polarity. This is usually shown on both power supply and laptop, with a + and - pointing to different areas of a picture. If the pics match, you're fine. If they're opposite (- points to inside on one, outside on the other), it's the wrong polarity. If this is the case, you can cut the DC side, strip the wires, rotate it 180 deg, and reattach to swap the polarity.
 
Brian Austin said:
Ditto this. If they're the same brand, you're fine provided the numbers match. If amperage (A) is higher on the older power supply but the voltages match, you're still fine. The battery will draw what it needs so A needs to be close or over. You're actually STILL okay with a lower A but it takes longer to charge and you may go into a deficit with the battery while using it.

Voltages need to match, though. Too much can hurt the battery and too little will not charge it.

Like Jesse said, check the polarity. This is usually shown on both power supply and laptop, with a + and - pointing to different areas of a picture. If the pics match, you're fine. If they're opposite (- points to inside on one, outside on the other), it's the wrong polarity. If this is the case, you can cut the DC side, strip the wires, rotate it 180 deg, and reattach to swap the polarity.

OK...brand is the same.

Found the polarity picture on the power adapter...a plus and minus pointing to a representation of the plug that goes to the back of the computer. The plarity is the same.

Output from the power adapter to the computer is the same for both voltage and amperage.

The only difference appears to be the amperage the adapter pulls from the 110v wall socket which is a little lower on the older adapter. I think I will give it a try.

Thanks all!

Len
 
Len Lanetti said:
OK...brand is the same.

Found the polarity picture on the power adapter...a plus and minus pointing to a representation of the plug that goes to the back of the computer. The plarity is the same.

Output from the power adapter to the computer is the same for both voltage and amperage.

The only difference appears to be the amperage the adapter pulls from the 110v wall socket which is a little lower on the older adapter. I think I will give it a try.

Thanks all!

Len
You're fine, then. The amperage from the wall is often an estimate based on full load. It's also dependent on what the power supply's efficiency is.

Sounds like you've got your second power supply.
 
Len Lanetti said:
Yes. IBM ThinkPads.

Len

Don't worry. They're our corporate standard and I've been using older power supplies with newer laptops for some time. In fact, I'm not sure that the docking station power supply would even plug into my T42. I think (I'd have to look to be sure) that they use a different plug. But the external supplies? No problem. The adapter we bought for use on airliners and in cars hasn't been changed in years.
 
Brian Austin said:
You're fine, then. The amperage from the wall is often an estimate based on full load. It's also dependent on what the power supply's efficiency is.

Sounds like you've got your second power supply.

Brian,

Thanks. I actually have a second and third power supply. Just call me the Scrounger. :<)

Len

PS Clicking through the channels last night after everyone was asleep...ran across "The Great Escape".

Werner: "Vat are you doing here by the truck?"
Scrounger: "I'm stealing tools."
Werner: "For stealing tools, cooler."

Len
 
We use Thinkpads in our company and we've used the same power adapters for years. You're fine.

I also pick them up on ebay dirt cheap. I just picked some genuine IBM adapters off of ebay and I paid like $17 for three of them (with shipping).
 
FlyNE said:
We use Thinkpads in our company and we've used the same power adapters for years. You're fine.

I also pick them up on ebay dirt cheap. I just picked some genuine IBM adapters off of ebay and I paid like $17 for three of them (with shipping).
Cool. Let me know if you can find some Nortel phone AC power adapters. I have two phones with no adapters after I gave one to my mom. When I checked a year or so ago most supply places wanted like $30. I found a surplus place that has a couple hundred for $5 each. I emailed to ask if I could get 4 or so and never got an answer.
 
At first I was bummed that I had a bunch of power adapters that wouldn't work with my new MacBook Pro...

But then I actually got the machine. Whoever came up with the "MagSafe" magnetic connection is a genius. I used to buy a new adapter every 8 months or so (they'd last 16 and I like having two too) but the connections would get looser and looser and finally end up worthless due to the abuse they go through in the truck and elsewhere.

Now, I only have one for the time being but this one is actually going to last, since with any kind of stress it simply disconnects rather than getting damaged. Genius. Pure, evil genius. :D
 
flyingcheesehead said:
At first I was bummed that I had a bunch of power adapters that wouldn't work with my new MacBook Pro...

But then I actually got the machine. Whoever came up with the "MagSafe" magnetic connection is a genius. I used to buy a new adapter every 8 months or so (they'd last 16 and I like having two too) but the connections would get looser and looser and finally end up worthless due to the abuse they go through in the truck and elsewhere.

Now, I only have one for the time being but this one is actually going to last, since with any kind of stress it simply disconnects rather than getting damaged. Genius. Pure, evil genius. :D
There are some home appliances like deep fat fryers that also have magnetic power cord sockets.

When I got mine home after the very first time I took it to work I couldn't connect the power cord. Without my glasses in the dark I couldn't figure out what I was doing wrong. With my glasses on I saw that the mag-safe socket had picked up an orphaned staple.
 
We went on a trip and my wife forgot her charger. When we got to the hotel, we asked security if they had one we could use. They pulled a whole box filled with chargers just for her brand. There were other boxes dedicated to various other brands. They told us to take our pick and keep it.
 
mdreger said:
We went on a trip and my wife forgot her charger. When we got to the hotel, we asked security if they had one we could use. They pulled a whole box filled with chargers just for her brand. There were other boxes dedicated to various other brands. They told us to take our pick and keep it.
I had never considered that. I buy two whenever I get a new laptop and keep one at home and one at work. That way I've got a spare and don't need to keep unplugging them.
 
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