usb-daq 6216 analog in

[MvdHeuvel]

Hai,

I am using a usb-daq 6216 for measuring voltage. I want to test a smps step by step. When i want to sample a channel, it does not give the correct value. When i use the scope, i see that the voltage is at the input of the adc. When i put a voltage on this pin using a lab dc source, it does give the correct value. Why does it not give the value i need when i want to test my smps? i tried diff mode and nrse mode. I do not use rse because i have no steady ground.

Can someone help me out?

Mike

[ninlmartijn]

Dear Mike,

Thank you for your post on our website. I want to ask fo some more information about your problem, this will help me to look in the right direction for a solution.

- what are the values you are reading with the daq card and what are the values with your scope (what is the value difference?)

- are you reading the values in the measurement and automation explorer? (please try first)

- please give a overview from the settings you are using (range, sample rate etc)

Best regards,

Martijn

[ninlmartijn]

Hello Mike,

It is a while ago since my last post. I hope your problems are solved. If not, please don't hesitate to contact me. You will find my phone number below this post.

Best regards,

Martijn Smeulers

National Instruments Netherlands

+31348-433466