how to set resolution of 6.5 digits

[MansoorEE]

I am using Agilent 34970A data acquisition and switching unit. I have been trying to set the resolution to 6.5 digits in the HP34970A confEZ.vi, but whenever I run the vi the resolution is 5.5 digits. I don't know how to change it to 6.5 digits.

[Sammy Z · Accepted solution]

Hi taarzan,

What happens if you set the resolution at 5.5 digits.  Do you get less resolution than 5.5?

Please make sure to set the precision before running the vi.

Does the manual of the device tell you that you can get 6.5 digits of resolution?

Regards,

Sammy Z.

[MansoorEE]

I have been trying to write a VI that configures Agilent 34970a to measure voltage with Range set as Auto and the resolution as 6.5 digits. I can set those configurations through hard selection but when I set range as auto and resolution as 6.5 digits  through (EZ conf.vi) ,which comes with the NI drivers for this insutement, the instument doesn't accept the 6.5 digits resolution and alway set 5.5 digits instead. This way, I can not get three digit precision. But, if I choose the a specific range lets say 10V the instument accepts the 6.5 digit resolution. But I want to go with the Auto Range with 6.5 digits resolution.

I don't know how to set Auto Range with 6.5 digit resolution through a labview's virtual insturment. Can you please help me with this?

[Sammy Z]

Hi Mansoor,

The only other thing that I can think of is to set the Resolution as MAX and the Range at Auto. 

If that doesn't help, you might have to give it a range instead of setting it as Auto.

Regards,

Sammy Z.

[Dennis_Knutson]

Have you actually looked at the code of Conf EZ? When autorange is selected, the case where the precision is set is not even called. The actual value that is sent to the instrument for precision also seems to be based on the actual range selected. I no longer have a manual for the device so you will have to confirm if what you want os possible with the instrument syntax. You could have a bug in the driver or seeing a limitation of the instrument.

[Sammy Z]

Thanks for your post Dennis.  You're right.   I overlooked the Auto case of the Range Case Structure.

Considering not having access to the manual, I wonder not having that case structure and running the non auto case for auto cases as well would give us the results that we need.

What do you think?

Regards,

Sammy Z.

[Dennis_Knutson]

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Sammy Z wrote:

Thanks for your post Dennis.  You're right.   I overlooked the Auto case of the Range Case Structure.

Considering not having access to the manual, I wonder not having that case structure and running the non auto case for auto cases as well would give us the results that we need.

What do you think?

Regards,

Sammy Z.

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It might. I used the 34970 for years, but I don't think I ever used autorange and don't remember enough. I may, if I'm feeling bored, download the manual but the op could easily test the commands in MAX.