Wiring for HP notebook power supply?

[Djard]

I have a 90 watt power adapter from an older notebook that will work with my HP DV5-1015nr. I transport my notebook between home and office. I'd like to utilize the older power brick, so that I won't need to transport a power adapter back and forth. The tips on both adapters, of course, are of a different diameter. So I bought a plug for the older adapter.

My multi-tester identifies that the tip is hot for both adapters. The older power brick has two wires: core wire to center pin (19VDC +) and shield wire to outer cylindrical part of plug (0 VDC -). The newer power adapter has three wires: shield wire connected to the core tip (delivering 19 VDC +), white connected to inner part of cylindrical plug (also 19VDC +), and black wire connected to outer part of cylindrical plug that must be the ground (0 VDC).

Logically the hot shield and white wires on the new plug need to be connected to the hot wire on the older adapter. I just need someone who is 100% certain to confirm this, so I can feel comfortable proceeding.

 

[Harvey]

If you're 100% certain that power adapters are both rated for 19 volts and the tip is hot for both supplies, your only other concern would be whether the older brick is rated to supply at least enough current at the rated voltage. It won't hurt anything if the supply is capable of delivering more than the required amount of current.

The spec page for your DV5-1015nr shows that the supply is rated at 90 watts. Most newer HP/Compaq machines require less power. For example, the specs for the PSU for my Compaq is rated at 65 watts. The label on the actual brick says it's rated to provide 18.5 volts @ 3.5 amps, which is 64.75 watts... but who's counting milliwatts. 😉

power (watts) = volts x amps. Therefore, power / volts = amps

90 watts / 19 volts = 4.7368421 amps.

As long as your older brick is regulated well enough that the voltage doesn't rise when delivering less than its rated current, you should be fine.

Another alternative would be to get a carrying case that has enough room to hold the original power brick. 🙂