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HP Forum Archive 11

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82002A charger diagnostic help
Message #1 Posted by Malcolm Brooks on 24 Mar 2003, 4:45 p.m.

I have a recently acquired 82002A charger that fails to output any DC voltage. Its the one for the 67 series.

I live in Oz 240V (No I didn't plug it into 240V) and this is a 110V US charger. It seems you just can't get any 240V versions anywhere. Anyhow not knowing that this didn't work I got a 110V converter. The converter works fine. The charger doesn't.

Any Ideas?

I measured some AC (yuk) about 3V on one of the pins. I really don't want to send it back to the US to one of the places that rebuild them as this will probably cost more in shipping than a replacement from ebay.

If its just a matter of replacing a few diodes then great. Can anyone give me any hints what to look for or replacement diode numbers?

Thanks Malcolm

      
Re: 82002A charger diagnostic help
Message #2 Posted by Vieira, Luiz C. (Brazil) on 24 Mar 2003, 9:31 p.m.,
in response to message #1 by Malcolm Brooks

Hi;

I have an 82002A and it has a 86 to 127 - 172 to 254 AC input select switch. I thought all 82002A were the same!

Mine came with the HP55 and I posted this message with the output voltages measured.

I hope this helps.

Success!

Luiz C. Vieira - Brazil

            
Re: 82002A charger diagnostic help
Message #3 Posted by Malcolm Brooks on 25 Mar 2003, 12:10 a.m.,
in response to message #2 by Vieira, Luiz C. (Brazil)

Ok, it probably really isn't an 82002A. The bottom plate is recessed but solid where the switch is on a real 82002A and it has a large sticker over almost the entire bottom plate covering this up. This sticker has the REAL number worn off. Its basically a 82002A with a 115V Transformer in it Non switchable.

Anyway somethings horribly wrong with it as I get NO DC Voltage reading but a small AC Voltage reading.

Thanks Malcolm

                  
Re: 82002A charger diagnostic help
Message #4 Posted by David Smith on 25 Mar 2003, 6:10 p.m.,
in response to message #3 by Malcolm Brooks

The first thing to check on these units is the big orange electrolytic cap. They are famous for going bad. You usually do see some DC, until you load the unit down. The parts inside are all common diodes and transistors. Tracing down the problem is usually quite easy.

And yes, HP did make some fixed voltage chargers. Basically they just bypassed the select switch and covered the hole with the stick on label.

                        
Re: 82002A charger diagnostic help
Message #5 Posted by Malcolm Brooks on 25 Mar 2003, 7:01 p.m.,
in response to message #4 by David Smith

Tony Duell emailed me and explained you will see some AC volts when the middle wire is broken if using a high impedance voltmeter.

Well he was spot on.

I couldn't easily check this as it the case had those torx heads with an anti tamper pin in the middle. I had to dremel the anti tamper pin to use a standard torx to open it.

Now I just have to slice the plug open and resolder the wires.

Thanks to all who replied esp Tony

Malcolm

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