Connecting NI 9218 with 9982f terminal block to full bridge load sensor

[Nitin.K.S]

Dear Members,

I am using NI 9218 module with 9982f screw terminal block to acquire load data from a HBM U9C load cell(it is 4 wire;full bridge sensor).

In the user manual of NI 9218(screenshot attached), it has been mentioned that the pin 3a and 3b are to be tied together for connection of 9982f block to a full bridge sensor. As I am from mechanical engineering background, I am not able to understand what "tying" exactly means. I have connected the wires as shown in the attached picture, but not getting required output in the graph. 

I request you to please help me out. I would be grateful for your suggestion.

Thanks,

Nitin

[Henrik_Volkers · Accepted solution]

Your connection looks reasonable.

Input noise ... depend on the sensor range ??

Offset of a load cell also depends on mountig position .. so you need a zero correction anyway 😉

Tied together on the board/connector means 3a and 3b are on the same potential since they are connected on the board/connector (just like if you have used a short wire and connect them by yourself) Since in some applications you want to connect two wires at pin 3 , NI was so kind to spend two physical connectors already beeing connected.

[Nitin.K.S]

Dear Henrik,

Thank you very much for your message.

1) Yes, I did a zero correction and have got rid of offset.(Scaling of the graph)

2) Thank you for explaining about the pin configuration of 9982f terminal block.

3) The sensor range is +/- 10kN. I am not able to get rid of the input noise. How is the sensor range related to the noise? And how can I remove the noise. 

Thanks

Nitin

[Henrik_Volkers]

Depending on your application a low pass filter will help .... Lowpass filter always help 😄 😄

about 100Npp noise ,reduced to the needed bandwidth by a factor of 10??

That's 0.1% ... what accuracy do you expect?

[Nitin.K.S]

Thank you very much Henrik for your genuine suggestion.