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I have an acer aspire one d255.

Would it be dangerous to use when plugged directly to current, without a voltage regulator. Also, is there a benefit in using the battery when plugged?

Let's consider that my fuses burn frequently (2, 3 times a year) and that are completely unpredictable.

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I generally encourage it to explain why you want to know something in your question and repeat the context of your actual question within the body of your question. – Ivo Flipse Feb 9 '11 at 0:34
Sorry, I edited it without thinking. I'll write some details UP INTO IT. – overmann Feb 9 '11 at 0:35
I greatly encourage you to get a qualified electrician to find out why your fuses burn out that often. – Matthew Lock Feb 9 '11 at 5:46
up vote 4 down vote accepted

Simply put, you should not run your laptop connected directly to the wall socket. A laptop power supply AC adapter brick is typically a simple AC to DC step down converter. Inside you will find a transformer and a bridge diode assembly which drops the 120 VAC to something like 20 VDC and a couple of capacitors to try to reduce ripple. The problems are as follows:

Say you have a brownout or low voltage condition which extends for awhile. The undervoltage causes a drop in output voltage which can cause your laptop to have issues dependent on whether the battery is installed. If installed, it should run from battery and eventually drain it down. If it doesn't, the computer may continue to run, but overheat due to the fans running too slow, and other devices starving for voltage. You may have errors, data corruption...

Say you have an overvoltage - it will cause the dumb bunny AC brick to pass too high a voltage - kind of the same issues - burned out circuitry...

Lastly even a full UPS is cheaper than some of those bricks, it is cheap insurance to use one. At least, use a surge protector.

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Now that's the experience doing the talking. Thank you! – overmann Feb 9 '11 at 0:45

That is completely dependent on local power conditions (e.g., frequent brownouts or surges) as well as the quality of the power brick.

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Oh geez. Then I have to install my regulator now isn't? – overmann Feb 9 '11 at 0:05
No it means that the chance is probably way within the spec of your netbook, unless you live in a place where the quality of the electrical system is really poor @overmann – Ivo Flipse Feb 9 '11 at 0:14
There was a time when we had a lot of black-outs, but now they are not that frequent, sometimes the fuses get burnt and we have to replace them. Is this enough motive to get a voltage regulator? – overmann Feb 9 '11 at 0:17
SORRY I EDITED MY QUESTION, EDIT YOUR ANSWERS. So you can deserve the point I gave you. – overmann Feb 9 '11 at 0:27

All laptops and netbooks are designed to work just as well without battery as with it to the point that many people advise leaving the battery out of the laptop unless you're charging it or using it, to prolong the batteries life.

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Except some recent Mac laptops, but only the ones where the battery is "nonremovable". – CajunLuke Feb 9 '11 at 0:29
Not all laptops! My Dell Latitude doesn't work with the battery disconnected. – Bryan Feb 9 '11 at 0:31

No, it is not dangerous to use the notebook while plugged in. The power supply of your Acer should be robust enough to handle minor current fluctuations. If your supply at the mains is unstable, you might want to use a surge protector, just to be on the safe side.

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I started using the surge protector, thanks for the advice. – overmann Feb 9 '11 at 5:36

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