Keithley DMM6500 Review & Scripting Tutorial (Python)

[@ahmedgaafar5369]

the debugging process is awesome, one thing i wish to do with mine is to run a script to automate I-V curve for a semiconductor device, to trace the iv curve of a diode or transistor, i kinda did something similar with the rigol power supply increasing voltage in steps and i acquired the current values directly into matlab ...man i love these things....thanx 4 this wonderful video.

[@CircuitAnalysis]

Awesome, thanks for the suggestion, that's a good project idea, I'll add it to my list. It would be great to have accurate parts data like that for making more accurate SPICE models. I'm also working on a programmable power supply so that would be a great way to test them both out at some point. IV for a solar cell could be cool too. Anyway I'll be excited to hear when you get your script working!

[@SurfinScientist]

Thanks for sharing! I assume that the same things can be done with the DMM7510, but wonder whether higher data rates can be achieved when sending data directly to a PC. Do you have any insights?

[@CircuitAnalysis]

Yeah I think it's supposed to be 1MSPS, but I was only able to get around 60 KSPS with that script. It seems like the USB and Ethernet should both be plenty fast enough to handle 16 bits at 1MSPS. Sorry I don't have time to try and figure it out right now, you might have to ask Keithley. I'd be curios though if you figure it out hah!

[@andreac3376]

For the amps measure, be sure to use the (white) amps HI input. Looked like your AFG connections were to the volts input on the dmm, but the script is putting meter into amps......

[@CircuitAnalysis]

Good call yeah need to be sure it's measuring volts! Just got a new function gen so maybe I'll try it again.

[@JuanMatinezCarvajal]

Hi, I would like to know if you have internal relays when you do dual measurements or when you change functions, like the Siglent SDM3055 or Hantek HDM3065 multimeters or the Uni-t 8000 series etc...

[@jordanclarke2996]

Great video thank you. After all this time are you still happy with your DMM6500?

[@CircuitAnalysis]

Yeah I mean I don't use it that extensively but for the level of accuracy and the name brand and the crazy feature set and nice look I think it's a good value.

[@jordanclarke2996]

@@CircuitAnalysis Thankyou. I just ordered one! Subscribed

[@CircuitAnalysis]

@@jordanclarke2996 Cool thanks for the sub!

[@jnygaarddk]

Cool video. Just FYI. The DMM comes with the Kickstart licence included. At least that's what I was told here yesterday, when I got my quote for the 6500...

[@CircuitAnalysis]

Oh awesome, thanks for the info! Might have to do another video!

[@Truth_seeker_24]

@@CircuitAnalysis I had the DMM6500 with me for 2 days (borrowed from a friend) and used Kickstart to play around and i noticed that the dc current measurement atleast doesn't match the accuracy on datasheet. Will be nice if you can get a precision current source nAmps and see how precise this DMM samples and outputs data. Very good video btw. Thanks for the debugging tips.

[@CircuitAnalysis]

Oh interesting thanks for the info. I don't have a precision source at the moment but I'll keep it in mind. What did you use or how were you able to determine it was inaccurate? Thanks for watching!

[@Truth_seeker_24]

@@CircuitAnalysis I used a precision Keith key smu and compared Keithley dmm, joulescope and a old agilent dmm under same smu source conditions. My load was a Bluetooth circuit where the current peaks are around 18mA and average current supposed to be around 11uA. Dynamic current measurement basically but it was within the dmm range against which accuracy has been mentioned on datasheet. I might still be wrong but if you wish you can get a precision smu and test.

[@CircuitAnalysis]

@@Truth_seeker_24 Awesome, thanks for the extra info. I will definitely keep that in mind for the future, especially if I'm trying to measure tiny currents!

[@brucetouzel6484]

can you mirror the DMM6500 display onto a monitor by simply using a USB to HDMI adaptor ?

[@CircuitAnalysis]

I really doubt it but I have not tried. I'm sure they would advertise it if they had added any video out, let us know if you find anything, thanks!

[@BoRRoZ]

Hi, tnx for the great review. I bought a DMM 6500 about a month ago, and when I plugged the AC in started making a loud humming noise . The device was not even switched on. So I send it back.. after googling a bit, I found that it seems a problem with the transformer production year 2020.. did you noticed anything similair ? I really want one but I'm afraid to buy another one and getting the same problem. I need an absolute (except sometimes the fan) silent one on my workbench. any advice ?

[@CircuitAnalysis]

Mine is 6ft from where I sit at my desk and I never noticed it making any noise when it was off, but I just put my ear up to the side vent hole and I can hear a 60Hz hum. I think your probably just had some defect/resonance though because I never noticed mine until I put my ear right up to it just now. Mine does have a humming sound from the fan as soon as it turns on, which you can hear rev up / down as it does its self check or whatever. It'd say when it's on it's about as loud as an average desktop computer. My old HP3478A DMM never seems to make any noise though so if quiet operation is a large factor then I would probably look for a fanless DMM. Good luck!

[@BoRRoZ]

@@CircuitAnalysis tnx !

[@Kmreddsadad]

I was curious about optional multiplexer card. It would be nice if you could set up demo

[@CircuitAnalysis]

Yeah, I didn't get the optional MUX. It's pretty expensive, but it definitely makes sense if you're building an automated tester for your company. I made a custom 8 channel mux that is controlled separately over USB for future projects. I may make a video about that someday but I'm pretty busy right now. Thanks for watching!

[@tonysfun]

Thanks for your video, but I need detail information how to create a SCRIPT to clear settings. I never done this before, none of my other meters have this function. Thanks in an advance.

[@CircuitAnalysis]

I don't have much more experience than what I showed in this video, but what are you trying to do? Clear what settings? Thanks for watching!

[@tonysfun]

@@CircuitAnalysis I like to reset everything back to default settings - like if I didn't mess with any settings that I forget - when experimenting. Thank you very much!

[@CircuitAnalysis]

@@tonysfun There are Channel, Measurement and System settings. You need to download the DMM6500 Reference Manual (just google it) to read all the options. You can make "Configuration Lists" to change between different setups. What I think you're looking for is under "Reset the instrument", page 141. It says the SCPI is "*RST" and the TSP is "reset()".

[@paytonbryce4101]

Do you know if there is way to measure DC voltage and current using this code?

[@CircuitAnalysis]

Yes but there's several things to consider. First, this is using the LAN and you might also want to use the USB connection instead if you're just connecting directly to 1 computer. Second, for standard simple measurements you'll want to use the standard SCPI commands (you don't need to worry about loading scripts onto the DMM like in the video). Check out the Reference Manual (link in the description) introduction to SCPI section starting on page 374.

[@joshbrown5138]

Accuracy may get thrown off due to switching between DCV and DCI functions. Some function pairs are better suited for getting multiple measurements at the same time (RTD measure & 4-wire Res, ACV & Freq or Per, etc.). If you can live within the confines of some ranges you might be able to take advantage of the DCV Ratio function for capturing V & I: www.tek.com/blog/measuring-power-using-your-keithley-dmms-ratio-function

[@CircuitAnalysis]

@@joshbrown5138 Cool thanks for the info, you sound like you work for Keithley or something? I was thinking of using this to measure current and voltage with a script to get input power to a power converter, what is the inaccuracy you are talking about with measuring both DCV and DCI at once? Can you wait a second or two and measure the other to improve accuracy? I was also curious if the rear ports are separate? Like for instance, could I hook the rear ports to the output of a power supply and the front inputs to the input and get the input voltage & current and output voltage and current all with a script to calculate efficiency automatically?

[@CircuitAnalysis]

Here's a link to some official examples I got from Josh Brown, I think his post disappeared so I'm pasting it again and also adding in the description: github.com/tektronix/keithley/tree/master/Instrument_Examples

[@Brucewayne777-r6w]

bro, how to read the data directly into excel one by one in real time rather than checking the saved file afterwards the check is complete

[@CircuitAnalysis]

Hey, sorry for the late reply. I have not tried directly connecting it to excel, but since MS doesn't support python natively yet I'd go with the built in VBA scripts. Here's an example of measuring temperature: forum.tek.com/viewtopic.php?f=617&t=140575&sid=a7c88b46756bfc2d0cf9557b7468bf1e If you go into the VBA editor in that file (alt+F11) and open up Module1, you can see in the "Run_Temperature_Scan_Click()" function how they are sending the standard SCPI commands using a line like "myStatus = commSend(instDMM6500, "*RST")". Using this example and the DMM6500 manuals you should be able to modify the SCPI to get the measurements you desire. If you want it to run continuously and automatically you could put your code in one of the excel reserved functions like "Workbook_Open()" support.microsoft.com/en-us/office/automatically-run-a-macro-when-opening-a-workbook-1e55959b-e077-4c88-a696-c3017600db44 and you could put it in an infinite loop with a fixed delay between readings.

[@frankp7063]

where to find functions.lua

[@CircuitAnalysis]

what?

[@frankp7063]

@@CircuitAnalysis I mean the functions.lua file that used in this code. I just copied the code from the note, but this program needs this file to execute.

[@CircuitAnalysis]

@@frankp7063 Oh, well it was in the app note in the description, but the link was broken so I just updated it. I'll paste it here too, it's a PDF and it's in the appendix: www.tek.com/en/documents/application-note/data-logging-power-profiles-wireless-iot-and-other-low-power-devices

[@frankp7063]

@@CircuitAnalysis Thank you very much