SCXI 1520 for potentiome​ter type pressure sensor

Question

I am usig 1520 for bridge type pressure sensor data acquisition.
I have a requirement for potentiometer type pressure sensors. The sensor is a potentiometer that needs 5V exciation.
  +---------------- Exc+
  |
  |
+--+
|   |
|   |
|   |<-------------- O/p+
|   |
|   |
+-+
 |
 |
 +---------------- Exc-
I was wondering if I could use 1520 for interfacing with such sensors?
I am hoping I can short P- and S- lines and connect to Exc-. P+ would be Exc+ and S+ would be O/p+.
The resistance between Exc+ & Exc- is of the order of 1-5 kOhm. So the current drawn from the excitation supply is of no concern for the 1520, I believe.
Can I do this with the 1520?

Answer 1

Dear Cas,
Thanks for your enquiry. You have obviously done a great deal of research into this matter already. I am afraid that it is unlikely that you will be able to use a single SCXI module to carry out all the functions you have listed. As accelerometers require such specialised conditioning, it will require a dedicated module - as you already mentioned, something like the 1530 (4 channel accelerometer input module) would be ideal.
However, you have a number of different options for the pressure, voltage and temperature measurements.
For example, you could purchase a 1520 mudule for your pressure measurements, and then use a general purpose 1102B for the voltage and temperature (you would require the 1303 isothermal terminal block to condition the thermocouple readings... and bypass the CJC technology for the voltage readings).
Or, perhaps you could use the 1102 thermocouple module for your temperature readings, and then use a 1102B to take the voltage and pressure readings. Obviously this would involve making your own bridge configuration for the pressure sensor, but that should be fairly easy.
Before you make any final decisions, I would recommend that you call your local branch of NI and speak with a sales representative. Perhaps, a member of the field sales staff could actually come to see you to discuss the matter face to face.
lastly, it sounds like you have a relatively high channel count for some of your readings, which is why you have decided to use the SCXI platform. I was just wondering if you had considered compact DAQ (cDAQ), which combines DAQ hardware with signal conditioning. Higher spec, ease of use, lower channel count. Swings and roundabouts I guess.
I hope this has been of some use to you.
Best wishes,
Rich R
Applications Engineer
National Instruments UK & Ireland