Archived:NI cFP-AI-111 No Voltage On The Vsup Pins

Updated Apr 17, 2018

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Reported In


  • cFP-AI-111
  • cFP-CB-1

Issue Details

I am trying to read pressure transducer readings with my cFP-AI-111 module, connected to a CB-1 connector block. My cFP-AI-111 Datasheet says which pin I should use for voltage supply, Vsup, and I am using the correct pin, but it has no voltage on it. The Compact FieldPoint is plugged in and powered on.


The cFP-AI-111 module needs external power applied to the V and C inputs of the CB-1 in order to output voltage on the Vsup pins. You can get an overview of how this should be wired in
  1. Connect the positive end of the power supply to your V connection.
  2. Connect the negative end of the power supply to your connection.
  3. Wire up your transducer according to either Figure 5 or Figure 6 (three wire versus loop-powered) in the FP-AI-111 and cFP-AI-111 Operating Instructions, depending on if the transducer is a three or two-wire connection. 
  4. Find the necessary pins for your connection on page 4 of the FP-AI-111 and cFP-AI-111 Operating Instructions. For example, using a three-wire transducer for analog channel 0, you would use pin 1 for I (in), and pin 17 for Vsup and pin 18 for COM (common ground).