IEPE Power supply needed for MCC 172?

[rodrigo12]

Hi,

I’m looking at the MCC 172 HAT to measure a couple of Kistler IEPE accelerometers with a raspberry pi, but I’m not sure if I would require an external power supply for the accelerometers with this solution.

As I understand, the excitation voltage for the sensors has to be around 18~30V, but with only 4mA of constant current.
Since the Raspberry is powered by a 5V / 3A power brick, I’m not sure if the power needed can be supplied by the HAT connected only to the Raspberry.
Still, the datasheet from the MCC 172 does say that you can turn on and off the IEPE excitation current via software.

I would appreciate your help in knowing if I would need an external IEPE power supply and if you could recommend one.

Link to the MCC 172 datasheet
Link to the accelerometer datasheet

[rick_1976]

Greetings,

The datasheet for the MCC 172 would appear to indicate that the necessary power supply for compatible sensors is incorporated into the board, being derived from the Pi supply by appropriate means. Insofar as this interconnect system seems to be based on using shared conductors for power and data, it would be reasonable for this to be the case, as the utility of the device would be rather compromised were it not.