New Fluke 87-V is broken

[ryann]

My parents were very nice to me for Christmas and bought me a Fluke 87-V multimeter.  I've worked with it since a few times, and I really like it.  Today, however, I seem to have killed it.

I wanted to put some labels on the multimeter.  I figured one label should go on the inside.  I took out the battery, lifted the back of the multimeter, and stuck the label on the back cover.  I put the cover back on, reinstalled the battery, and checked to make sure it still worked.

Well, it didn't.  I have no idea what I did.  I literally popped the cover off, and popped it right back on.  I made sure the mode selector switch on the inside was on the OFF position, I checked for foreign object debris, and I measured the battery voltage to make sure it wasn't dead.  Everything checked out well.

I did more investigation.  I took off the LCD & plastic plate, as well as the shield.  No FOD here.  I checked underneath the mode switch.  All the plungers? looked straight and springy, and the contacts on the PCB looked clean.

I have no idea what's wrong.  Fluke is closed today, so I plan on calling them tomorrow to see how well their lifetime warranty works.  In the meantime, please review the video below and give me some other non-warranty-voiding ideas.

Thanks,
Ryan Nazaretian

Here's the video.
https://www.youtube.com/embed/rSrLYSoCnyM

[ryanblace]

Take it apart again and make a video of it operating without the front cover like the picture. You can rotate the white selector (there is an arrow on it) with an allen key.  I have a feeling that the selector isn't lined up correctly.

[retiredcaps]

ModemHead's blog post gives an idea of how it works (could be specific to the original 80 series)...

http://mrmodemhead.com/blog/fluke-83-dmm-repair/

"Also, there is the potential to engage the switch hub with the knob via its hexagonal shaft in such a way that it is not aligned properly.  This would allow the switch hub to be rotated beyond where it normally stops."

[ryann]

I don't think that's an issue here.  I recorded a video, but I have to edit it because my mom and our puppy walked in while I was recording...  It's clearly lined up properly.

College kid at home problems... 

[ModemHead]

The V generation does not have the PTF/voltage-divider style code switch on the back, so it can't be that.  (No rotary switch self-test either.)  But there's obviously something wrong with the rotary switch, specifically that portion of it that indicates which function is selected, to the micro-controller.  It's out of sync with how the front end is configured, hence the non-sensical results.

I haven't taken any of 'V' generation units apart, and I haven't seen any publicly available schematics for it either, so I can't come up with any more specific advice.   

[ryann]

Sorry for the long awaited video... I had to clear out about 20GB of space in order to edit the video... then it failed to export a few times.  Finally got it done.  Uploading to YouTube now... so be patient.  It says about 40 minutes left.

http://youtu.be/pQmxFV6C9Kw

I'm going to give Fluke a call later today.  I have some outdoor chores to do before the weather gets bad.

Thanks again!

[ryann]

I called Fluke today.  They told me the same with the knob being turned the wrong direction.  I told them that it was correctly assembled, as can be seen in the video above.  I shipped it out today, and hope to get it back sometime next week. 

[retiredcaps]

It will be interesting if they tell you what the problem was.  Please report back after you hear from Fluke.

[ryann]

Just got it back.

On the service paper, they said they replaced U2. I saw somewhere that it's a AD737J, which is an RMS-to-DC converter. It doesn't make much sense why that would cause all the problems I was getting. They performed a calibration and sent it back. Seems to work as far as I can tell.

[ModemHead]

Thanks for the report.  You're right, that doesn't make much sense.  But no matter as long as it works now!