Underamped Power Adapter

darkguy2

Honorable
Oct 4, 2013
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So I have a HP mobile workstation for work that came with a 200W power adapter (19.5V 10.3A) that is quite large and heavy. For travel I got a 150W (7.7A) charger that was compatible with my laptop. Now the laptop is rated for 10.3A. My problem is that even the 150W charger is a pain to carry with me when I travel for work and would like to get a smaller one. There is a 90W travel adapter that supplies 19.5V 4.62A that is much easier to carry around. My question is if the 90W adapter would be able to handle the strain of my laptop when I use it on the road?
 

greens

Distinguished
Jan 27, 2012
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A few things.

The PSU will charge the laptop when the laptop is not in use. It will be slower but will work just fine.

When the laptop is in use the PSU will be dedicated to powering the laptop. It will probably not charge at all while the laptop is in use. It will probably require 100% load of the PSU, which means it is going to heat up.

Once the adapter has sufficiently heated up, it will begin to perform poorly. As it performs poorly it will try and compensate and cause it self to heat up even more. What you'll end up with is a thermal runaway, eventually resulting in short or shut off of the PSU, depending on quality. This could be a built in safety feature, or just end in fire.

It is a tough call as you can see as it can go either way.
 

greens

Distinguished
Jan 27, 2012
244
0
19,160
71
A few things.

The PSU will charge the laptop when the laptop is not in use. It will be slower but will work just fine.

When the laptop is in use the PSU will be dedicated to powering the laptop. It will probably not charge at all while the laptop is in use. It will probably require 100% load of the PSU, which means it is going to heat up.

Once the adapter has sufficiently heated up, it will begin to perform poorly. As it performs poorly it will try and compensate and cause it self to heat up even more. What you'll end up with is a thermal runaway, eventually resulting in short or shut off of the PSU, depending on quality. This could be a built in safety feature, or just end in fire.

It is a tough call as you can see as it can go either way.
 

dudio

Admirable
What Workstation model do you have, and we can maybe check specs on what type of power requirements it truly has.
Personally, cutting back that far on Watts/Amps means the power supply will be straining to supply what the hardware wants, and could crap out, potentially taking some of the laptop with it.
 

darkguy2

Honorable
Oct 4, 2013
9
0
10,520
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Zbook 15 G2. The weird thing is that some places list it as compatible with the 90W charger. I think I already knew the answer, but was hoping someone would tell me otherwise.
 

dudio

Admirable
Seems unanimous :(
Specs on your laptop show the two supplies you already have. Anything less is risky.

"Power 150 W Slim Smart AC adapter (external); 200 W Slim Smart AC adapter (external)"
 
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