New Keithley DMM6500 and now DAQ6510

[thm_w]

I found a problem on my DMM6500: The terminal switch (Front/Back) had a contact problem. With the inputs shorted ohms measurement was between -0.5 and 2-3 ohms, depending on how quickly I released the switch. Put some Contact Cleaner in the switch and now it always reads -0.5 ohms. This offset goes over the whole range, even at continuity measurement (as expected). I never used the switch before, and all readings were good until I used it the first time. Seems they calibrated it in the factory with the unwanted contact resistance. The unit is eight months old, so I suspect Keithley won't recalibrate it for free? Or is Keithley customer friendly?

Magnus

Contact them and let us know the result. I would not mention using contact cleaner.. this is almost certainly going to void the warranty.
I would say you cycled the switch and it started happening.

[Kleinstein]

Adjusting the Ohms zero is often a separate adjustment point that the user is supposed to do from time to time if accuracy in 2 wire ohms matters. So one would likely not need a full recalibration, just that one zero point.
Still it is no such a good indication of quality if they do not catch a poor contact in the initial testing (maybe even the self test). Ideally the initial value at zero adjustment should have told them that the switch is bad and may need rework.

[Magnum]

i will contact them and see what happens.

Another thing I saw when it was open: Pressing the switch bends the pcb badly. I don't want to use this switch very often...

[Magnum]

Adjusting the Ohms zero is often a separate adjustment point that the user is supposed to do from time to time if accuracy in 2 wire ohms matters. So one would likely not need a full recalibration, just that one zero point.
Still it is no such a good indication of quality if they do not catch a poor contact in the initial testing (maybe even the self test). Ideally the initial value at zero adjustment should have told them that the switch is bad and may need rework.

That would be the solution, as the offset goes over the full range. Of course I can use REL, but adjusting it would be better. Any idea how to do that, does someone have the calibration manual?

[cozdas]

does someone have the calibration manual?

In the tektronix manual page, if you select the "service" as the "Manual Type" you can reach the calibration manual. This link should for a while too: https://download.tek.com/manual/DMM6500-905-01B_%20Nov_2018_cal.pdf

[Magnum]

does someone have the calibration manual?

In the tektronix manual page, if you select the "service" as the "Manual Type" you can reach the calibration manual. This link should for a while too: https://download.tek.com/manual/DMM6500-905-01B_%20Nov_2018_cal.pdf

Thank you for the link. Made the zero Ohm calibration, and everything is fine now.

[Wintel]

does someone have the calibration manual?

In the tektronix manual page, if you select the "service" as the "Manual Type" you can reach the calibration manual. This link should for a while too: https://download.tek.com/manual/DMM6500-905-01B_%20Nov_2018_cal.pdf

Thank you for the link. Made the zero Ohm calibration, and everything is fine now.

Made the zero Ohm calibration by yourself?

[Magnum]

Yes, with the Keithley Shorting Plug.

[MegaVolt]

Does zero calibration shift the entire scale?
Those. was 10V will become 10V - zero offset. So?

[Magnum]

Does zero calibration shift the entire scale?
Those. was 10V will become 10V - zero offset. So?

i only checked with Ohms: It shifts the whole range like REL does.

[Magnum]

You can try it yourself: Make the zero calibration, but don't save it. Then you can verify all reading. When you switch the unit off all changes are gone.

[hugos31]

I want to buy a second use, does anyone have one for sale? I'm in Peru (South America) 

[HendriXML]

I'm considering buying the DMM6500.

What I like about the unit is the data acquisition possibilities. But after reading through this whole thread I also saw some issues that where pointed out.
The issue that a current trough the current measurement path interferes with the voltage measurement is a bit of a set back.
Also it seems that the technical person of Keithley doesn't interact on this thread anymore, that is a bit unfortunate.
Also In the datasheet I've read it has a fixed forced cooling, however in a video comparing the fan sounds to another device, I can hear it changing. Also in this thread 2 speeds are mentioned.
So what to expect regarding fan noise.
When I write scripts for my other devices, I mostly do that remotely anyways, but in other usages not having a lot of fan noise would be a plus.
I know every case has its best matching device, but as this being a hobby, in my situation it's sometimes otherwise. The case is then matching the device possibilities. Using and exploring gear is a large part of the hobby.
So for me the question would be: is the device fun to use (not to many crashes/bugs, fan noise) and is it accurate enough to make the efforts using it in experiments worthwhile, and also has it also matured enough in its current FW state?
(About the accuracy: I think it should be more than enough.)

[cgroen]

I'm considering buying the DMM6500.

What I like about the unit is the data acquisition possibilities. But after reading through this whole thread I also saw some issues that where pointed out.
The issue that a current trough the current measurement path interferes with the voltage measurement is a bit of a set back.
Also it seems that the technical person of Keithley doesn't interact on this thread anymore, that seems a bit of a bad sign as well.
Also In the datasheet I've read it has a fixed forced cooling, however in a video comparing the fan sounds to another device, I can hear it changing. Also in this thread 2 speeds are mentioned.
So what to expect regarding fan noise.
When I write scripts for my other devices, I mostly do that remotely anyways, but in other usages not having a lot of fan noise would be a plus.
I know every case has its best matching device, but as this being a hobby, in my situation it's sometimes otherwise. The case is then matching the device possibilities. Using and exploring gear is a large part of the hobby.
So for me the question would be: is the device fun to use (not to many crashes/bugs, fan noise) and is it accurate enough to make the efforts using it in experiments worthwhile, but also has it also matured enough in its current FW state?
(About the accuracy: I think it should more than enough.)

I can answer a couple of your questions. I got a DMM6500 some months ago and liked it so much that I bought one more a few weeks ago! The fan is a total non-issue for me, my Agilent 34461A is louder (and that one does also not make much noise). Now, I also have a Keithley 2281S-20-6, and that one is LOUD !
I have had one single "blue screen" on my (first) DMM6500, this was while trying to save data from a session (24 hours, so a couple of bad words came out of my mouth....) but other than that I have had zero problems.

And I agree, it is so sad that Keithley is no longer active in this thread!!!

[HendriXML]

I can answer a couple of your questions. I got a DMM6500 some months ago and liked it so much that I bought one more a few weeks ago!

That sure solves the second measurement issue , good to hear you like it so much!

[HendriXML]

Because of the many positive responses (1/1)  I pulled the trigger, and ordered myself a dmm6500. It's a bit too deep for my bench, so that's needs sorting out.

[KedasProbe]

Yes it has issues but up to 1MS/s with touchscreen and viewable/controllable on your PC screen.
These are damn nice features for me.
It bridges the gap between scope and DMM.

I even checked the clock signal of my I2C bus with it instead of starting/connecting my scope, yes it can trigger on a waveform.     (a Rigol scope that makes much more noise)

I do wish the hum noise (also when powered off) was lower . (I think it's a bit lottery how loud yours is)

Using it for current and voltage both connected at the same time, I would just avoid unless you really know what to expect. (the same is actually true for almost all other alternatives)

[HendriXML]

All my devices power-cables are inserted in 2 of those sockets (image), I've one screwed down on the left and one on the right. So it's easy to switch devices completely off. Having a label on the wire is handy as well. This way I can easily shut all stuff down with 2 switches when I'm done. Simple and cheap. (These are Hama's and of ok quality (1.5 mm2 wire)).

[PTR_1275]

That’s a neat power board. I’ve seen them with individual switches or a main switch, but not individual and main switching.

[HendriXML]

They have also some overvoltage protection  But that they are bolted down on the edges is a real space saver. In a way they are barriers to keep also other things falling of the edge.

I think that for the dmm6500 I extend my desk and create a platform for my scope at the same time. The sketch is a bit exaggerated and not scaled but shows the idea. The long bolds which tights the extension to the desk use those Ikea style nuts that are placed in sideways.

It won't be a 'pretty' solution, but otherwise the dmm is just a bit too long.

If the fan of the dmm is too noisy, I might go for a more enclosed extension with locally placed sound adsorption. That might lower it by some db's.

[PTR_1275]

What other equipment do you have? The 6500 fits on the same shelf I have for my keithley 2015, agilent 55320 counter, siglent AWG and rigol dp832 power supply plus a lot of other equipment.

Depending on what you plan to do in the future, you may find having a bench with the depth for the 6500 will become a lot more useful.

[HendriXML]

This DMM will most likely be my last (measurement) device, so future proofing of space is not really needed. (For my skill level I consider myself sufficiently equipped: Scope, hand MM, psu, awg)
So I'll first see how the desk addition works out.

[HendriXML]

I got a DMM6500 some months ago and liked it so much that I bought one more a few weeks ago!

I think you also bought yours from www.cnrood.com? Did yours come with a calibration certificate?
Mine came without one.

Also what would be the path to get the free licence for free kickstart?
https://www.tek.com/promotion/free-kickstart-software-purchase-dmm6500-or-dmm6510

As for the fan, I can live with the noise. It's less noisy than my scope.

Is there a way to check how much (turn on) power cycles the unit has? I want to reassure its new and not one that has been send back for whatever reason. (It did come with 2 identical power cords for instance and no certificate, which makes me wonder whether its straight from the factory. The state I got mine in is not consistent with the 2 unboxing video's on YouTube.)

[cgroen]

I got a DMM6500 some months ago and liked it so much that I bought one more a few weeks ago!

I think you also bought yours from www.cnrood.com? Did yours come with a calibration certificate?
Mine came without one.

Also what would be the path to get the free licence for free kickstart?
https://www.tek.com/promotion/free-kickstart-software-purchase-dmm6500-or-dmm6510

As for the fan, I can live with the noise. It's less noisy than my scope.

Is there a way to check how much (turn on) power cycles the unit has? I want to reassure its new and not one that has been send back for whatever reason. (It did come with 2 identical power cords for instance and no certificate, which makes me wonder whether its straight from the factory. The state I got mine in is not consistent with the 2 unboxing video's on YouTube.)

Yes, I got the first from cnrood (at a discount), the second one from Farnell. They both came with a calib. certificate and did not look like they had been opened previous etc!
Not sure about the turn on cycles, havn't seen that one!

[Kleinstein]

The number of turn on cycles would be odd and not that helpful for normal use. With a LM399 ref. inside the hours active for the reference would be nice to have, but I doubt they have it.