NI 9234 Max IEPE current

[Harrivin]

Hi, 

I would like to connect perform noise measurement with my NI 9234. The 9234 spec sheet mentions min IEPE current supply is 2mA and typical current supply 2.1mA. Is there a max current limit as I notice some microphones specify 4mA constant current source? There are current ranges specified which start at 2mA, but I was also wondering what is the significance of this 4mA.  

Thank you. 

[santo_13]

NI 9234 has a fixed 2mA IEPE current as depicted in the below diagram

Unfortunately, not a of accuracy specification is provided for the IEPE source but it is not required. As to why 2mA and 4mA, it would have to do with the power requirement of the sensor and limit the IEPE compliance voltage.

If you're looking to use a 4mA sensor with NI 9234 - NO, it will not work since the instrument can source only 2mA (typical).

For example, a more advanced DSA - PXIe4464 has 3 configurable IEPE current values and can support a wide range of sensors.

[Harrivin]

Hi Santhosh, 

Thank you for the clarification.