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# Is it okay to replace a 7A power cable with a 10A cable?

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April 17, 2012 4:46:41 PM

Need to get a longer power cable for the charger that came with my Lenovo Ideapad (only 3ft). Looking at a 6ft cable that is identical in every way, except that it's rated at 10A instead of 7A. That doesn't mean that it will draw more power than is needed correct?
April 17, 2012 4:50:45 PM

No just that it can handle more power. It will work fine.

Thent
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a b D Laptop
April 17, 2012 4:51:35 PM

it means there will be more amps going through the cable
ur risking burning something up since it out of the manufacturer's specifications.
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April 17, 2012 4:53:56 PM

alvine said:
it means there will be more amps going through the cable
ur risking burning something up since it out of the manufacturer's specifications.

It shouldn't draw more amps than it needs though right?
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April 17, 2012 4:56:15 PM

The AC/DC Adapter states the input as100-240V @ 1.5A. Meaning it draws 1.5 Amps from the wall. This should mean that the amp rating on the cables only really needs to be above 1.5. So a 10A rated cable should be no different than a 7A rated cable.

Correct?
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a b D Laptop
April 17, 2012 4:57:28 PM

YOU are fine. The input should really say 100 V @ 1.5A and 0.75Amps for 240V
The real Max current from the wall is approx 5A x 19 Volts / 120V or in the case of 220 divide by 220
If talking about the end that plugs into the wall.
Let's see laptop brick typically 19V @ < 5 AMPs = 0.8 Amps at the outlet.
7 Amps is Overkill, But absolutly NO problem going from 7A -> 10 Power cable.
Only diff is that if you develope a short it will handle 10 Amps before it starts to melt/burn LOL as the Fuse should blow first!!.

If Talking about the end that plugs in to the Laptop. The 10 AMP cable will allow 0.05 Volts more at the laptop, good but NO BIGGY. PS this is do to a Lower IR drop for the larger conductor.

Added. IGNORE alvine 's comment - simply NOT TRUE. The current is dictated by the Load, not the wire ga of the power cord!!
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April 17, 2012 4:59:15 PM

You are correct Stalker. (I am an Electrical Eng.)   you are good no worries I have done this many times a power supply only pulls from the wall what it needs/is being used. So going up is fine down would be bad and could get hot catch fire ect.

Thent
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a b D Laptop
April 17, 2012 5:00:51 PM

alvine said:
it means there will be more amps going through the cable
ur risking burning something up since it out of the manufacturer's specifications.

Current doesn't work that way Alvine
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April 17, 2012 5:01:02 PM

alvine said:
it means there will be more amps going through the cable
ur risking burning something up since it out of the manufacturer's specifications.

Wires don't force current to be drawn by a device, the device will draw the current it needs to operate, a higher rated cable is just thicker and can handle more current without heating up.

Typically the same can be said for wall tranformers and power bricks, however if the transformer is able to source more power than the device needs, it can get a lot more energy going through it 'if' it is failing (if it shorts out for example), so it's not a bad idea to use the proper amperage (or close to and above it) when replacing a bad wall transformer.
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April 17, 2012 5:11:58 PM

RetiredChief said:
YOU are fine. The input should really say 100 V @ 1.5A and 0.75Amps for 240V
The real Max current from the wall is approx 5A x 19 Volts / 120V or in the case of 220 divide by 220
If talking about the end that plugs into the wall.
Let's see laptop brick typically 19V @ < 5 AMPs = 0.8 Amps at the outlet.
7 Amps is Overkill, But absolutly NO problem going from 7A -> 10 Power cable.
Only diff is that if you develope a short it will handle 10 Amps before it starts to melt/burn LOL as the Fuse should blow first!!.

If Talking about the end that plugs in to the Laptop. The 10 AMP cable will allow 0.05 Volts more at the laptop, good but NO BIGGY. PS this is do to a Lower IR drop for the larger conductor.

Added. IGNORE alvine 's comment - simply NOT TRUE. The current is dictated by the Load, not the wire ga of the power cord!!

Ah, that's what I was thinking. Thanks for the in-depth clarification.
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April 17, 2012 5:12:14 PM