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It'll take a few days for a new adapter to arrive for one of the laptops which has the following input and output voltages

input: 100-240V ~ 1.6A 50-60hz

output: 18.5V 3.5A LPS

The other adapter has the following input and output voltages

input: 100-240V ~ 1.5A 50-60hz

output: 19V 3.42A

2
  • Your old adapter might not have been a perfect match either. It's worth checking what voltage your notebook actually needs. This information is usually printed on the bottom. Providing a higher voltage definitely comes with risks that are hard to quantify. For what it's worth, I'd plug it into my notebook without hesitation. May 16, 2013 at 19:45
  • @Marcks Thomas - Do you mean at the bottom of the laptop? If there is a difference between the voltages, is it still worth plugging it in? May 16, 2013 at 19:49

6 Answers 6

3

I would not use the other adapter. It provides too much voltage (these should be exact):

19V > 18.5V

And it doesn't provide enough current (it's alright if the adapter provides more, but not less):

3.42A < 3.5A

It's possible that it could work, depending upon how tolerant the Laptop is, but I wouldn't risk a laptop that I don't want to replace if the outputs on the adapters don't match up exactly

2

Bad voltage mismatch and bad amperage mismatch each have different kinds of consequences.

With voltage, slightly underdoing it can result in performance problems, which could lead to hard drive problems (data corruption, etc.) but slightly overdoing it (no more than 10% or 20.5v total in your case) has never caused me any problems (I repair laptops and am stuck with mismatched power supplies all the time).

With amperage, even slightly overdoing it can fry components. But if your power supply is under-amped, you won't damage anything - the laptop simply won't start.

(This is my personal experience and also the "rule of thumb" taught to me by a guy who built audio receivers - he apparently learned a lot by trial and error when it came to this.)

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  • 2
    I agree: A slight over-Voltage (<10%) is not a problem. Over-Amperage could be damaging, but on a laptop it's usually not a big problem if the difference is less than 10%. The loader-circuit for the battery usually smooths this out. In this case the user is OK. Only the battery might re-charge a bit slower than usual.
    – Tonny
    May 16, 2013 at 20:22
  • @Kristen Jukowski - So there is no risk of frying the laptop? May 16, 2013 at 20:46
  • I would say with your given specs, no - you won't fry the laptop. Like @Tonny said, you're well within tolerance in either direction. And amperage is lower on the substitute supply, which is on the safe side. If anything, the laptop just won't power on. May 16, 2013 at 20:59
  • 2
    The laptop will draw the current it needs, no more. The adapter's current specification merely indicates the maximum current the power supply can provide. 'Slightly overdoing it' won't fry components. Massively overdoing it is completely harmless too. May 16, 2013 at 23:10
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1

It may be okay to use the other adapter just by reading the specifications you've provided alone. The lower amperage should be okay because it doesn't vary by much from the amperage from the original one.

The problem lies within the voltage regulator inside your laptop. Since those 18.5 (19) volts are being reduced to microvolts for your motherboard components, you would need to see the tolerances of your voltage regulator. I would assume that a half volt difference should be tolerable, but I'm just guessing without any solid numbers. If you're the paranoid type, or don't want to risk it, I would get the specs on the voltage regulator first.

0

You should always match Voltage EXACTLY to avoid damage. Previous poster said it is okay to go over voltage by like 10% and I COMPLETELY disagree esp. with sensitive electronics that can overheat!

When it comes to Amperage, you need an amperage that is greater than or equal to the original label on the device which is the MAX amperage it can supply. The device will only pull the amount of current it needs but the this minimum amperage is a requirement or you may end up with insufficient amperage issues.

Actually getting a supply with double the max amperage spec is usually more efficient because the supply runs at about 50% of its rated max load and most supplies running at 50% load are way more efficient than running them at 100% load. They will pull less juice and produce less heat!

A previous poster commented that higher amperage is a problem. That is completely INCORRECT information. Only lower amperage is a problem!

Finally, no one mentioned about POLARITY and the POLARITY MARKING! Make sure the replacement adapter is the CORRECT POLARITY or it won't work or worse, damage your device!

-1

You need to know the AC power specifications first of both items and they need to agree for best performance

-1

Adapter-2: E2=19V I2=3.42A I2 in AC= 1.5A;

Adapter-1: E1=18.5V I1=3.5A I1 in AC= 1.6A;

E=Voltage; I=Amps; W=Watts;

W DC=E DC * I DC;

Adapter-2 capacity of electricity:

W2=E2*I2=19*3.42=64.98 Watt

Adapter-1 capacity of electricity:

W1=E1*I1=18.5*3.5=64.75 Watt

Deviation accuracy capacity of electricity:

(W2/W1)*100%-100%=+0,36%

Replacement should be of the same polarity, the difference in the supply voltage does not exceed 0.5V, and have sufficient capacity.

Not use 10% criteria to laptop power supplay!

In general, post it became clear that the power is almost identical ... it was possible to finish the ode Electrical and arithmetic, but we have a little torment to useful conclusions.

Deviation accuracy voltage:

(E2/E1)*100%-100%=(19/18.5)*100-100=+2,7%

Deviation accuracy DC:

(I2/I1)*100%-100%=(3,42/3,5)*100-100=-2,3%

The efficiency of conversion from AC to DC:

W1~W2; E1 AC = E2 AC;

(I2 in AC/I1 in AC)*100%-100% = (1.5/1.6)*100%-100% = -6,25%

Wow! Adapter-2 - very good!!!

Use it. Good luck!

Watch for temperature. Watch for characteristics of supply power at different CPU load as possible.

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