Keithley DMM6500 - random jump touch issue

[bb9900kk]

Dear everyone,

My unit was bought from Jan 2023.
Running firmware 1.7.12b version.
Serial number:  04576280
This issue only appear around 1-2 month recently.
Unfortunately, until now (Sep 2024), my warranty was expired.
I recorded issue, please refer it for more detail.
(Sorry for not very good my video quality & and annoying sound from continuous failed).

Video 1:


Video 2:


I hope this issue can be fixed in some next firmware release.
In my point, I think it will be better for customer if have an option in System Setting.
- Option "disable touch" feature, and support external USB mouse via USB port on the front this product.

I already create a ticket support on Textronix support, wait them answer.
If you have any idea, please let me know.
Thanks.

[tooki]

I doubt it's a firmware problem.

The display is clearly sensing touches that aren't there.

The DMM6500 uses a capacitive touch screen. This means a few things:
1. the display is sensitive to contaminants that are conductive
2. noisy power can cause issues

I'd start with turning it off and giving the display a cleaning with a tissue and a bit of water and alcohol. Make sure it's dry.

Then make sure your meter's mains power is properly grounded. Use another meter to test continuity to ground. (The back panel of the meter should be grounded.)

I assume you have an oscilloscope. Use it to see if there is unusual EM noise. If there's something around generating static, that could be an issue.



As a last resort, it's probably possible to just replace the LCD. Keithley may sell it, and otherwise, it's probably an off-the-shelf part you can find a replacement for.


P.S. I would not use the word "automatic" (or the short form "auto") to describe unwanted behavior -- that word indicates something happening on purpose, which is the exact opposite of what you mean here.

[bb9900kk]

Hi Tooki,
Thanks for your fast reply.

Indeed, I already try cleaning it with a tissue and a bit of water and alcohol (Alcolhol 70 DEG).
I also try turn on/off power many times...
I also doubt this is firmware issue, because I still can touch to all that button, but just some seconds later, it often jump touch to "Cont" or "Diode" mode...

"Then make sure your meter's mains power is properly grounded. Use another meter to test continuity to ground. (The back panel of the meter should be grounded."
=> Unfortunately, in my Vietnam country, we don't have a ground system, it's not easy to make a ground for my home.

About EM noise => yes, I have a Rigol DS1054Z.
While try reproduce this issue, all other equipment is turn off. I don't see any strange EM noise.

"P.S. I would not use the word "automatic" (or the short form "auto") to describe unwanted behavior -- that word indicates something happening on purpose, which is the exact opposite of what you mean here."
=> Yes, I also think some word such as "random" - because it's not intended.

Thank you again.

[voltsandjolts]

My unit was bought from Jan 2023.
...
Unfortunately, until now (Sep 2024), my warranty was expired.

Not sure about your purchase but beware that these units normally come with 3 year Keithley warranty.

[squadchannel]

If you bought used, might be a problem in transit. panel is banged? bump something?

[bb9900kk]

Hi Voltsandjolts,
I bought that unit from EMIN dealer in Vietnam.
They only warranty 1 year for that product

[bb9900kk]

If you bought used, might be a problem in transit. panel is banged? bump something?

=> Ah, No. I bought it's a new full box product.
I bought it from Jan 2023. It's working no problem until 1-2 month recently.

[HighVoltage]

I think you can buy a warranty extension for the DMM6500

Just don't let anyone see this thread.