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Scan Engine: FailSafe value for output nodes

Status: New



I noticed there seem to be no way to guarantee the state of an output module controlled by a scan engine in case the RT Application (or the Host Application, depending who is controlling the chassis) crashs. With FPGA one can program some kind of watchdog setting back the output values of a module in case the RT Exe fails. With Scan there just seem to be no possibility.


This is why I think adding a FailSafe Value for a Scan I/O node could be a creat idea. in ase the RT application got aborted  or stops  without cleanup, the output value would not be random no more but set back to their FailSafe value. I imagine it could look like that:




What do you think about it?

Florian Abry
Inside Sales Engineer, NI Germany

That would be a useful function. 🙂

NI Employee (retired)

That would be very nice. 🙂

Active Participant

This could also be useful for more distributed systems (like ethercat for example). If I am not mistaken, the only way to get ethercat devices (9144) or the equivalent ethernet chassis (9148) into a safe state upon connection loss is to write custom FPGA code. It would be pretty cool if this were a core feature of the scan engine for systems like that.

Active Participant

9144 has a built in watchdog and safe stating of outputs.

Stephen B
Active Participant

True story (kb here for anyone interested:


What I was looking for but failed to actually say was that I wanted to have a configurable failsafe as shown in the picture. But I failed to use my words 😞