Repair a PAN 8209. A challenge for you !!!

[juan3211]

Hi,

I usually work with Arduino and small projects with 12VDC or smaller systems (solar, batteries, Li-Ion, etc)

The fact is that I have a PAN 8209 panControl DMM 8209 (i think there are also rebranded ones, or may be it is rebranded one) and last itme I has produced strange errors.

They are frequent errors AND randomly, but I have seen them measuring continuity or voltage meter.

When I measure currents they do not happen.

They can happend with differents probes, but they are produced randomly.

Sometimes, when I measure voltage, DMM starts beeping and fails to establish measure. I have to turn it off and turn it on. And, in some cases, even doing off - on doesn't help.

In continuity I have seen less, but also it randomly doesn't work as you can see in the video. (photos of inside at the final part)

https://youtu.be/ZD7Na3akCxE

When they are "batteries", it usually works well, then I suspect it may be some noise in the signal that blocks the DMM.

I've opened it looking for a broken capacitor, but I have not seen any swollen or broken.

It isn't an economic issue, DMM is more or less cheap so it could be thrown away, but sometimes we do challenges for ourselves: could I repair it?

Anyone know where I can start?

I would like some help, but maybe all the answers are ... "not worth"

In this case, I thought of replacing it with a UNI-T UT136B or UT139C (for house-plugs or higher voltages I have a clamp meter). What do you think of both to the use I'll give to them. Can the UT193C temperature  probe be used to see the temperature in transistors, MOSFETs, heatcoolers,  ... ?

NOTE: I have already put a new 9V battery

Thank you for your help

Regards,

[retiredcaps]

In continuity I have seen less, but also it randomly doesn't work as you can see in the video. (photos of inside at the final part)

Let's start with a clear focused still picture of the pcb (both sides).  The photos in youtube are not good enough for me to see.

It isn't an economic issue, DMM is more or less cheap so it could be thrown away, but sometimes we do challenges for ourselves: could I repair it?

Yes, I repair low cost items generally for fun, challenge and learning purposes.

Anyone know where I can start?

In some of these low cost meters, I suggest checking the range switch for dirt/debris/contamination.  Bad or cold solder joints can also be problematic in low cost meters.  Clear focused well lit pictures will help us help you.  If I can't reading the silkscreen writing on the pcb, then the pictures are not good enough.

[juan3211]

Hi, here you have better resolution photos.

https://reviewschinas.wordpress.com/dsc_8314/
https://reviewschinas.wordpress.com/dsc_8316/
https://reviewschinas.wordpress.com/dsc_8318/
https://reviewschinas.wordpress.com/dsc_8326/
https://reviewschinas.wordpress.com/dsc_8328/
https://reviewschinas.wordpress.com/dsc_8333/

Thanks.

[retiredcaps]

The board seems to have a lot of stray solder bits leftover from the manufacturing process.  In addition, the range switch contacts all look dirty.

I suggest giving the entire pcb a 91% IPA bath and letting it dry thoroughly (probably overnight).  You can also use a clean toothbrush to help remove the dirt/debris with the IPA.

[juan3211]

Thanks a lot.

About UT136B and UT139C have you got any preference? (i know they are very very cheap)

regards,

[retiredcaps]

About UT136B and UT139C have you got any preference? (i know they are very very cheap)

I don't have any Uni-T meters and have used neither so I can't comment first hand.

[juan3211]

About UT136B and UT139C have you got any preference? (i know they are very very cheap)

I don't have any Uni-T meters and have used neither so I can't comment first hand.

Thanks a lot.