Attenuation and noise adding SCXI-1125 and SCXI-1327

[__behemot_]

I am trying to measure 6 signals and results of all are incorrect.

My modules: PCI-6251, SCXI-1001, SCXI-1125, SCXI-1327.

Three of my signals are rectified 230VAC, and other three are digitals (different frequency, max 7kHz), with high level 3V3.

I have two kinds of problems:

1. Measured signals are different then real (also different then signals measured at the same time on oscilloscope)

2. Three digitals signals are deformed by the other signals, even when I disconnect this three shape of digitals signals is still incorrect

3. Measured values on oscilloscope are deformed and incorrect when I connect SCXI module with board (it does not matter is SCXI1001 is turn ON or OFF)

My settings:

hardware junctions: three digits: 1:1, three AC 100:1

software attenuation: three digits 1, three AC 100

Sampling frequency: three digits 16kHz, +/-5V, Three AC 1kHz, +/-300V

What is wrong with this measur devices or what I should change in my measure settings to get correct results?

[e2m0i0l7]

Hello,

This looks like quite a complex topic for the forums.

I suggest you to contact the your National Instruments branch for troubleshooting your system and identify whether it is an architecture problem or faulty HW.

You can find a toll free number for your country by visiting: 

www.ni.com/country  (country- name of country of origin)

Thank you

Emil 

Please relpy if you managed to get in contact with your local representative