Keithley 2000 Frequenzy Measurment over GPIB

[Blanky]

Hi,

Im using a Keithley 2000 Multimeter over GPIB with LabView 8.5.

The measurments normally do just fine, but when I want to measure a frequenzy all frequenzies over about 90Khz are just showed as 0. If I measure it manually it works and gives me the right frequenzy.

Im using a NI GPIB Adapter.

Did someone ever expirienced a similar problem ? Is something known about a bug ?

[NathanT]

Hello Blanky,
       Have you contacted Keithley about this issue?  It very well might be an issue with the instrument's firmware.

Let us know what they have to say,

NathanT

[Blanky]

I wrote to them, itll now i got no anwer...hopefully they can help

[NathanT]

Hello Blanky,
     While you are waiting to hear from them it would not hurt to upgrade to the most recent firmware.

Cheers,

NathanT

[Blanky]

Hmm, there doesnt seem to be a new firmware, at least not on the manufacturer page...and google.

[Rikud]

Nathan,

Yes, you are on the right track to deal with the manufacturer of your unit. I would send your labview program, detailed description of your frequency source and voltage level, and details about your unit s/n, f/w to the manufacturer at applications@keithley.com.

Since I also have several units (mine all have latest A20 firmware...which as someone pointed out hasn't changed in several years), I tried using my arb source at 100KHz and had no problems with my units. I could try your lv program if you can attach it. Could you also give some details about your freq source voltage level would be useful.

regards,

--stuart

[Blanky]

I am using the predefined functions from the GPIB-USB adapter manufacturer, I think there should be no problem.

I attached the program, you need however the instr.lib functions from agilent (model 34401). My voltage level is at 100-400V, it works at none of this levels.

[Blanky]

I have not heard of the keithley customer support for a while now...

nevertheless, i resolved/found my problem. It seems to be a combination of a instrument bug(?) and my measurment application, because i have tried it with several other things, and there it worked, just not with that one (measurment over a pearson probe)

Thanks to everyone who helped.