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Implementing safeties in VeriStand

What are your experiences with implementing safeties in VeriStand?  I have used them in the past and have had some limited success, though I've not worked with them enough to know the limitations.  We did have a hydraulic test stand about a decade ago that was running VeriStand, which was doing a multi-day continuous test with safeties implemented, and we had a computer crash overnight.  Because the system was set up where the SDF was deployed to the NI controller, but the stimulus profile that was running (using WTI Inertia) was native to the host computer, when the computer crashed, the NI controller just got locked on the step in the profile where it was at that time.  Luckily it was in a benign step in the profile, but it could have easily been in a much worse state.  We will have a need to run another similar test sequence, and I need to try to figure out how to implement safeties properly.  Any advice/experiences would be appreciated.  I'm not sure how to overcome the computer crash scenario, so I'm particularly interested in thoughts for that one.

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Try GitHub - NIVeriStandAdd-Ons/Host-Heartbeat-Custom-Device

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Control Lead | Intelline Inc
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That's a custom device I've not seen, thanks.  I'll give it a try to see if it will cover the computer crash scenario.

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We use a Watchdog Tool created by Wineman / Genuen that toggles variable on the host PC.  It is a .vi that is added into the project and runs on deployment - very simple and very light.  Because it is on the host PC, when the host PC disconnects from the cRIO real-time target, the variable that is changing state stops, which triggers a VeriStand alarm to shut the test down.  

If you have a relationship with Genuen - I would reach out to them.  It works great for us for power outages and when ICT updates force shutdowns of test cell PCs.  

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we use this model to a DO to a BRENTEK    watchdog relay device.  The model will toggle at 1/2 your loop/model frequency

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