Notebook Power Supply

[Tioleco]

I have a power supply for an compaq notebook with these specifications:
18.5V / 4.5A , but the max power indicated in the label is 45W , this is right?
The power should de 83W!
The model is Delta Electronics , Compaq PP2032 P/N 401882-001

[kaboom]

Re: Notebook Power Supply

Load it up with a 4 ohm resistive load. Those old compaqs were funny.

The nameplate on my LTE5400 calls for 18Vdc at 2.6A. The adapter is rated at 18Vdc, 1.9A. That adapter will indeed supply 18V at 1.9A. While delivering a current of 2.5A, the voltage fell to 15V. I used an extra adapter as a maintainer for a small SLA battery. With the regulator I made, a discharged (~10.5V) battery would pull the 2.5A indicated above. Of course, current dropped off as battery reached full charge.

Get a large ceramic resistor, Dale, Ohmmite, Vishay, etc. 4ohms/25W, and put it across your adapter. If it's rated 'normally,' you'll have your 18 volts across it and ~4.6A thru it. But if you have substantially less, it's 'power limited.'

I never figured out why compaq did that. One would think of current limiting while charging the batt, but if the system is on, charging times are nuts.

Dead batt, system on: 1.5-2 hours, depending on CPU load, etc.
Dead batt, system off: usually around 45 minutes.

Before you doubt the adapter, determine if it powers the connected equipment properly. Does the laptop power up? Battery charge if still good?

I've got a boost converter that I made. I connected it to a big 13.8V bench supply and set it for 18V at 4A. I used that to power the old dinosaur. This is subjective, but there was no difference whatsoever between those two power supplies.

-Paul