strain measurement SCXI 1520 Signal Express

[OKors]

Hardware= SCXI-1000, 1520 bridge board w/ 1314 terminal blocks
Software= NI-Max, Signal Express v1.1.1

Trying to configure a simple uniaxial strain gauge within Signal Express.
A common setup for us is to measure Load and Displacement along with multiple strain channels. I can create, calibrate, and run a strain channel within NI-max by adding a new task under NI-DAQmx in Data Neighborhood but this is as far as I can get.

How can I configure this same strain gauge within Signal Express?

Thanks in advance.

[MickeyD]

Hello,

Sounds like you did a good job setting up your hardware and got it working in MAX.  In signal express you can add a step, then from that you can select Acquire Signals » NI DAQmx Acquire.  Once you get there you can choose which device to acquire from.

Singal Express v1.1.1 will have your DAQ device listed with a "+ modules" next to it under device in the configuration tab.  You can then add a channel for any module in your SCXI chassis.  One important thing to consider is that you might want to make a global channel in MAX, which you can then select in Signal Express.  It depends which interface you prefer to set up the channel in.

This KB has a walk through of how the screen should appear.  Can SignalExpress Acquire Data from SCXI or SCC Modules?.

Please let me know if you need any further information so we can stay on top of your issue.

Have a great day,

Michael D
Applications Engineer
National Instruments

Message Edited by MickeyD on 12-07-2006 01:46 PM

[OKors]

Thanks for the friendly reply.

I've figured out how to add a strain channel from SigEx by using the "Create NI-DAQmx Global Channel...". This raises a couple more questions:

• Once a strain channel is created (and saved), will it retain its calibration settings when called up again in Signal Express?
• Also, will I have to re-wire the terminal block each time my bridge configuration changes, I.E. going from full-bridge, to quarter-bridge, to half-bridge?

Thank You

[MickeyD]

Hi,

Glad to hear you got a global channel up and working.  The first answer is yes the calibration settings will run when signal express calls the global channel.  The second question I am somewhat confused.  It seems that you would have to rewire the connection to your terminal block to use a different strain gauge.  I would recommend making a global channel for each of the strain gauge configurations.  This way you can simply change the device setting in signal express. I think that would be the most flexible way to implement that change, but I do think you will have to physically change the wiring into the terminal block.  Please let me know if you need further assistance.

Thanks,

Michael D
Applications Engineering
National Instruments