Best Method

[Davenj]

I would like to set a coil and reset it when the High Speed counter input stops then restarts.  Trying to stop an output when input stops, then restart it input restarts. The output runs at varying rates based on input frequency changes.

 

Dave

[Flex727]

You will need to define what you mean by "input stops". If the interval that defines "stops" is large compared to the largest (i.e. lowest frequency) count interval than the problem is easy. Otherwise the problem can be very difficult. Do you have some other signal available that will tell you when the input is off?

[Davenj]

The inputs a constant stream of pulses.  The pulses represent flow from flow meter.  Flow starts and stops fueling by an operator.

[cantcliff]

Use  a timer that resets each pulse, then if the pulse doesn't come within the time period allow the timer to expire and trigger your next state.

[Davenj]

Thanks,

I have two HSC counter inputs and use those to get a total Gallon Per Minute flow.  Used the GPM to stop the Output, and restart when flow starts.  The Output runs to maintain a PPM range for flow.  The problem arose at high flow rates and running near the low PPM limit the Output would keep running until it caught up.  No acceptable with no flow.  This method worked, will try yours and one from Uni support team.