Sir mattfara . . . . .
Tell ya’ what I’m gonna do . . . . . .
I will just tack your connection explanation to the units schematic, just in case you . . .or any others . . . . are up against repairing one of these units.
The HEAVY outer shield cable is the negative connection and the inner shielded line is the +19 VDC output.
Just keep the inner white wire clipped off and possibly insulate its then small wire end from, any external contact.
FYI . . . .
It is being a Dallas ONE WIRE digital buss between this PS and a companion digital interfacing within the computer.
Info is exchanged as well as a handshaking to have the computer showing a connection error being displayed, if this specific HP power supply is not being used with the computer.
You can disregard all aspects of that . . . as you will get your +19, if being connected as I have shown.
Is this a second supply that ‘ole computer guy gave you . . . . with profuse apologies for the first bad ? one, I presume, as you now seem to be his “test bed” .
TECHNO SUPPORT INFO:
Thassssit . . . .
73’s de Ed
Actually, I picked this one up from a thrift store - $4
The guy who gave me the first power source suggests that the first power source broke because it was not providing enough power. He claims that because of the variable voltage of the light bar, the power consumption can change. Here is his email:
"
Matt,
Ok, the specifications you sent me are very vague. Having variable input power will change the total wattage needed. Let me explain.
1.3 Amps @ 12 v = 15.6 Watts
1.3 Amps @ 13 v = 16.9 Watts
1.3 Amps @ 14 v = 18.2 Watts
1.3 Amps @ 15 v = 19.5 Watts
1.3 Amps @ 19.5 v = 25.35 Watts
1.3 Amps @ 28 v = 36.4 Watts
Now, the Specs also said 18 LEDs @ 3 Watts each. Making that 54 watts.
@ 19.5V @ 54 Watts makes it 2.76 Amps.
@ 12V @ 54 watts makes it 4.5 Amps
@ 19.5V @ 99 Watts making it 5.07 Amps
Now the specs would need to be way off, and the LEDs draw 5.5 watts each, making it 99 Watts and that would bring it around 5 Amps on the draw, and would explain the burned out power supply.
There are so many options you can go with for a new power supply. Sorry it died on you.
"
This email confuses me because the specs of the light bar say that the power consumption is only a bit under 18W. Would power consumption change with voltage? The specs certainly don't suggest this, given that they allow for a range of voltage but only list a single value for power consumption.
Is it more likely that the first power source was just faulty?
As for the wiring you showed, the inner most wire is the digital bus, which I should clip/insulate, correct?
Lastly, thank you very much for your ongoing guidance. Very encouraging for a new hobbyist.
Matt