Keithley 2400 connect with computer using rs232 to usb cable

[jasonim]

As I already said, I have 2 more cable.

I tested it every cable with keithley2400 and there were no issues.

[cstorey]

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@jasonim wrote:

As I already said, I have 2 more cable.

I tested it every cable with keithley2400 and there were no issues.

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What do you mean by no issues?  Your answer is unclear.

 - You tried the other cables,  install drivers correctly and you are able to properly communicate with the K2400 

OR

- The other cables behave exactly the same way:  they show up as COM4 but are unusable with ANY instruments.

I think your problem is the USB-RS232 adaptor.  Have you tried another instrument and had it work with any of your cables?  If the USB-RS232 adaptor is unable to communicate with any instrument then its is definitely the issue.  Just because the PC recognizes something at COM4 doesn't mean the adaptor is working properly and the K2400 is not.  That's the real frustrating part about the adaptors that don't work!

How to proceed..

0 - Verify your USB-RS232 cable.  What make model is it?  Is it a straight tru or cross-over cable?  (You want straight thru!)

1 - Verify the cables actually work.  Try to communicate with another instrument.  Try a physical  RS232 - RS232 cable with the K2400 if you have an RS232 on your PC.    Maybe borrow from someone who has a test setup and can communicate with that instrument.  If you can't communicate with a known working instrument with your USB-RS232 adaptor then the problem is the adaptor.

2 - Try to communicate with the K2400 using a different setup.  Try a USB-GPIB adaptor instead of USB-RS232 or try another PC with a working USB-RS232 adaptor?

3 - How old is the K2400?  What firmware is it running?  Perhaps upgrade the firmware to the latest version and try again.

I've used dozens of K2400 and several USB-RS232 brands.  The problems I've had are 9/10 due to USB-RS232 cable and driver issues.

Craig

[jasonim]

I tried another cable(it is also rs232 to usb cable used another pc, working well)

But it is same. 

and I confirmed the version of firmware. this equipment has rev33. it is updated march 2015.

So i also tried to update this firmware but i can't because it also need to communicate with cable.

connecting another pc has same result.

[cymrieg]

There is a YouTube video about why this Prolific USB to RS232 adapter won't start on Windows. This is shown in your screenshot of the device manager with an exclamation mark.

https://www.youtube.com/watch?v=vsb2k1etImg

Focus on getting Visa Interactive to recognize the COM Port first.

[jasonim]

Finally, I solved this problem by switching the cable to RS232-RS232 cable.

I think the problem was the cable and windows 10.

I really appreciate you guys help me a lot.

[Minions]

Then show your appreciation by marking Message 12 by cstorey as the Solution and any others that helped with Kudos.

[AnalogKid2DigitalMan]

Some older chips used in USB-RS232 cables do not work in Windows 10.

Had one that ran fine in Win7 for years and when OS was updated to Win10 it no longer worked. Research confirmed my statement above and purchased a new cable which worked.

-AK2DM

[arnab33]

what drivers did you install for connecting the keithley instrument with the labview setup using the usb