New Keithley DMM6500 and now DAQ6510

[frankvh2]

Perhaps this has already been said. But for those upgrading the firmware of the DMM6500. If your 6500 currently has a version less than 1.7.10, consider doing what I did and first install 1.7.10. You need to use the "downgrade" button to perform that update. Then, after 1.7.10 is installed, use the "upgrade" button to install the latest version - 1.7.12 as I write this.

In my case, my DMM6500 had 1.7.5 installed. So I downloaded both 1.7.10 and 1.7.12 from the Tek website. First installed 1.7.10 using the "downgrade" button, then installed 1.7.12 using the "upgrade" button. Why? So that the firmware version displays correctly. Doing it this way avoids that annoying bug where only 1.7.1 is displayed.

[aronake]

Hello dear E-Design!

I can't find any information in datasheet about what β-value you are design for NTC 10k temperature measurements?

I try use DMM6500 on NTC 10k with β 3870K but i see it is incorrect value, when i moving from 25С to any direction i see too much error.
It's looks like as you are using β-value too different... Maybe you use β-value around 34**K?

Also - how i can measure NTC 10k in 4-wire mode? (in Keysight DMM like as 34410A i can enable that mode)

(Attachment Link)
Model number: 44006 is specifically mentioned for 10k thermistor in the specifications document.
https://www.mouser.com/datasheet/2/261/44006-275331.pdf

This is helpfull, but have anyone found other thermistors that work well?

[aronake]

Hello dear E-Design!

I can't find any information in datasheet about what β-value you are design for NTC 10k temperature measurements?

I try use DMM6500 on NTC 10k with β 3870K but i see it is incorrect value, when i moving from 25С to any direction i see too much error.
It's looks like as you are using β-value too different... Maybe you use β-value around 34**K?

Also - how i can measure NTC 10k in 4-wire mode? (in Keysight DMM like as 34410A i can enable that mode)

(Attachment Link)
Model number: 44006 is specifically mentioned for 10k thermistor in the specifications document.
https://www.mouser.com/datasheet/2/261/44006-275331.pdf

This is helpfull, but have anyone found other thermistors that work well?

Some more research and this seems to be the beta value for the different thermistors:

Model   25C ohm    Beta
44004    2252            3978
44007    5000     3976
44006    10000    3694

A beta which is 200 wrong gives an error of around 1 degree at 40 degrees. So depending on intended use, can be quite OK to have a beta wich is 100 or so off.

[thom]

Hi everyone,
I have tried to write some script to improve/repair awful default diode test. My script works as on good old flukes (e.g. model 45) - as old as me probably

Here is what script can do:
-one beep: when you are in range (0,25V..0,8V).
-no beep: when you are above,
-contstant beep: when you are below.
-frequency for sound is 2kHz (not this original shitty sound).

All seems to be fine when script is running BUT I observed some really big problem: after switch-off script and go to regular mode e.g. voltage measuring all is ok. When I switched-on script again meter became unusable. Sometimes is just one sequence on-off-on, sometimes two when unit is stop responding. The only rescue is reboot unit.

Could one of you can confirm this? Please find tsp file in attachment.
I thought that in my script some routine at the end like "reset buffer on exit"  is missing however I dint find something like this.
What is wrong?

this script is wonderful and solves my only real complaint with this meter, but it locks up my meter after closing it once or twice. meter build july '22 running FW 11b. I'm going to play around with it  and see if I can get it to work without crashing. strange that it works fine for some people and crashes for others

[jord4231]

I've had a bit of a search around and have not seen this come up yet (although it may have)
Am I going crazy or is this a bug?
The issue is with the notify command forgetting its assigned to timer.

I think its a bug.
Anyone seen this before 
https://youtu.be/g9NauzUXyR0

[E-Design]

I've had a bit of a search around and have not seen this come up yet (although it may have)
Am I going crazy or is this a bug?
The issue is with the notify command forgetting its assigned to timer.

I think its a bug.
Anyone seen this before 
https://youtu.be/g9NauzUXyR0

Does look like something buggy going on. If it is not too inconvenient for you, I would suggest post your issue here:
https://my.tek.com/tektalk/digital-multimeters

Some developers might see it and possibly log the issue for you.


EDIT: Nevermind! I see that you did already.

[jord4231]

Ah turns out it's user error
As pointed out to me in that Tektronix fourm when modifying the timer I must then click enable timer!

[jimjam]

So it's now February 2023. If I were to buy a new DMM6500, would it still have these problems?

• Transformer hum (240V, 50Hz)
• Poor viewing angle on the LCD screen
• Lock up / freeze / crash when running certain scripts, e.g. simsys.pl's Diode tester script

[KaneTW]

No transformer hum on my unit after a RMA (although they said nothing was changed). Viewing angle is subjective, so can't answer that (it's ok for me). No idea about the firmware bugs.

[HighVoltage]

My unit was one of the early deliveries.

1. I never had any transformer hum
2. The viewing angle is perfect for me
3. Since the firmware has been updated significantly, I also have no problems there.

[zrq]

I would be more interested in where can one get it as cheap as few years ago  .

[HighVoltage]

I would be more interested in where can one get it as cheap as few years ago  .

Those days probably never come back.

[zrq]

I would expect it will slowly come back as now China has ended zero-COVID and back to 100% productivity. There are some uncertainty given the geopolitical situations though.
Also with the pressure of Chinese DMMs, just like how Rigol and Siglent changed the low end oscilloscope market. I have no idea how good those meters are compared to A brands, but more competition is certainly a good thing.

[Hydron]

The old prices were conspicuously low compared to the KS competition, so I wouldn't be so sure they'll get down to that level again. I had to RMA mine for the transformer thing but it was an early unit, and no regrets about the purchase (especially at the old price )

[zrq]

Well, but the Keysight competitors are also few hundred bucks cheaper few years ago. So I'd still wait a bit.

[jimjam]

The FOMO in me says "What if it goes up even more!"

[goaty]

Wow what happened there? I paid roughly 1k€ new unit when it came out, now it's at 1,6k€ in some places. Inflation ?

[MikeP]

 Hello.

 Please help. Is it possible to configure a trigger to turn the multimeter into a window comparator? That is, keep the trigger output high at a certain voltage range. Or is it necessary to write a script for such a task?

 Besides I ask to assume high-speed performance of this system. Yes, I understand that there is a direct relationship with accuracy. Is a reaction time of less than one tenth of a second achievable for an error of tens of millivolts in the 10V range?

 Or is it still easier to assemble an "iron" comparator

 Perhaps someone is familiar with the solution, I will be grateful for the hint.

 Thanks.

[HKJ]

Please help. Is it possible to configure a trigger to turn the multimeter into a window comparator? That is, keep the trigger output high at a certain voltage range. Or is it necessary to write a script for such a task?

Why not use the limit settings in the Calculations menu.

[2N3055]

Hello.

 Please help. Is it possible to configure a trigger to turn the multimeter into a window comparator? That is, keep the trigger output high at a certain voltage range. Or is it necessary to write a script for such a task?

 Besides I ask to assume high-speed performance of this system. Yes, I understand that there is a direct relationship with accuracy. Is a reaction time of less than one tenth of a second achievable for an error of tens of millivolts in the 10V range?

 Or is it still easier to assemble an "iron" comparator

 Perhaps someone is familiar with the solution, I will be grateful for the hint.

 Thanks.

There is a Reference Manual for the meter.
https://download.tek.com/manual/DMM6500-901-01_A_April_2018_Ref_DMM6500-901-01A.pdf
Chapter 9-17,  Analog Triggering. 

[MikeP]

 Thank you friend! This is exactly what I was looking for. 

[ar__systems]

Got DAQ6510+7700.

Using a PC to drive repeated scan of 11 channels. The reason for using the PC is that I also need to control a power supply (turn it on for the duration of the scan, then off). The power supply has only USB interface.

Pretty cool piece of equipment, I should say. The reason I got here is that I first tried to configure the 7700 to control the power to the DUT, which is possible, but only if you use fewer than 11 channels for measurements, and I have 11 Found some posts floating ideas of replicating the 7700. I started to think of modifying the 7700 to allow that with more than 10 channels. Probably will never do it: I don't want to ruin my brand new device, and it is easy to add a serial port controlled relay with FTDI or something like that. ...and I still need to drive everything from a PC since I need to also take an image from a camera.

[qmichl]

If somebody is interested I want to share some update to the MeasurePower script that has been published by Mike G earlier here. The major changes are:

• Use of FILL_CONTINUOUS buffers which allows to run it endless
• The measurement is not done in a loop anymore, but uses a timer to trigger it

The changes are based on this description of unoffical functions: https://github.com/tektronix/keithley/tree/main/TTI_Apps/TTI_Display_API

Rename the txt file to tsp file to use it on the instrument.

Disclaimer: There is no guarantee that the unoffical functions still work after a firmware update, I tested on 1.7.12b. So, no warranty.

[Mike G]

Thanks to qmichl for the link to the unofficial information which I was not aware of. 
I have not had time to work with more projects for the 6500 lately but have some ideas for the future. 
Some of the information in this unofficial guide I had already worked out the hard way but there are several very interesting features in here that I was not aware of.
Thanks again qmichl

[Baltazar]

As some have reported, operating the front/rear terminal switch bends the PCB. So the idea is to avoid using it as much as possible.

If the switch is in FRONT position, can I still use the 10A & INPUT LO connectors on the back with the specified accuracy to measure current in the 10A range?