Keithley 2700 / 2701 / 2750 DAQ Bench Meters

[KungFuJosh]

I recently got a couple of these 2700s. One has B09, and the other B05 firmware. B09 should be straight forward to update, but it looks like I would need to recalibrate if updating B05.

Any tips/thoughts on updating the B05 version? I'm assuming there's a way to backup the cal data safely. Also curious about user calibration/adjustment if that's an option.

Thanks,
Josh

[KungFuJosh]

One other question...

What e-caps are usually in these? Both seem to have what look like recent Nichicon caps.

Thanks,
Josh

[KungFuJosh]

I updated the unit with B09 to B11, and it went fine. There was a +516 error once after upgrading, but I assume that's because the memory was cleared during firmware upgrade.

It took 21 minutes and 26 seconds to complete in fast upgrade mode. 

Thanks,
Josh

[KungFuJosh]

I decided to upgrade the second meter as well. It had fw B05 on it, which is supposed to be annoying for some reason (fw notes says recal required), but it was fine. 🤷

From the firmware notes:

In rare instances where customers choose to Downgrade from B06 or higher to version B05 (or lower) the instrument will require a recalibration to preserve the accuracy of Low Frequency AC measurements.

From the service manual:

Semi-permanent storage facilities include NVRAM U136. This IC stores such information as instrument setup and calibration constants. Data transmission from this device is done in a serial fashion.

I connected U136 to a couple different programmers, and either it was empty, or encrypted. So, I ignored it and moved on.

After the firmware updates were done, I did some comparison tests and they all look pretty good to me.

Thanks,
Josh