Hi,
Can anyone help me find answers to the below listed clarifications on the design of NI PXIe 4330 SC Express module.
1. The specification says there's short-circuit protection between EX to GND pins.
1.1. Is it safe for the 4330 module to have a sustained short between EX and GND?
1.2. How is the short-circuit protection triggered? If the sensor has a problem and starts to draw more current, does the 4330 unit shut-off the excitation
supply? i.e. from the point of the sensor and harness, is the excitation source current limited?
2. I have piezo-resistive (NOT piezo-electric) full-bridge pressure sensors that are in Wheatstone bridge configuration. Since they too work based on
'change in resistance', I am assuming they work fine with 4330. Please confirm this.
3. Is there any spec for maximum resistance of the arms of a full-bridge? My piezo-resistive
sensors have resistances (between EX and GND and between OP+ and OP-) in the range 3kOhm to 6kOhm.
4. How is the grounding/return scheme for excitation and analog-input?
5.1 Do all channels share the same EX- line?
5.2 Is there any isolation between channels? Are all channels completely independent?
6. In case of a failure in the module, what is the maximum excitation voltage that can appear at the output? Can it be reasonably proven that a voltage limit
exists for exciation that cannot be exceeded under no circumstances?
For example, if the module is powered by 12V, we can reasonably argue that in case of a failure of any component, the voltage cannot exceed 12V. Can a
similar argument be made for the 4330?
Thank You.
Warm Regards.
Sagar G Yadav
