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Set "auto-detect" 3 or 4-wire RTD in Create Virtual Channels.vi

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I am trying to setup a NI 9216 RTD module in a cDAQ chassis.   DAQmx Create Virtual Channel allows me to set the RTD type as 2-wire, 3-wire or 4-wire:

Create Virtual Channel.JPG

The Getting Started Guide says that the NI 9216 auto-detects whether 3- or 4-wire RTDs are connected but there does not seem to be an "auto-detect" option in the Create Virtual Channels vi. 

 

If I leave the resistance configuration input unwired I get an error message

"Requested value is not a supported value for this property. The property value may be invalid because it conflicts with another property."

I have tried un-wiring some of the VI inputs such as excitation source but I then get a message saying the default input is incompatible with the 9216, so I cannot do without them.

 

I get the supported value message regardless of whether or not an RTD is physically connected to the inputs.

Am I missing something?

 

Thanks

Roger

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Hello Roger,

 

You are correct the 9216 will auto detect. 

 

However, you still need to configure the DAQmx Create Virtual Channel (VI). The default within LabVIEW will be 2-wire as this is the first value offered in the enum connected to this input.

 

Not sure how you would get LabVIEW to do detect if it's a 3 or 4 wire configuration. There will be a way of doing this but you will probably need to use DAQmx property nodes. 

 

Thanks,

Michael

 

 

 

 

 

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