Software filter for signal with spike

[GerdW]

Hi Steven,

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@StevenD wrote:

Is there any benefit to using min max as opposed to in range and coerce?

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IMHO it would be more readable code…

[Henrik_Volkers]

After solving a hardware (EMC)  problem in software (always valid, however ...) 

maybe it will also help to reduce the cause of the spike 😄

Spikes caused by acting solenoids can be greatly reduced by 'freewheeling' diodes at the solenoid (without meters of cable) and/or RC snubbers.

The sligthly reduced acting speed of the solenoid (some ms fall off delay) usually don't matter.

And propper wiring! Mainly different 'GND' wires for power and signal , minimizing groundloops, use twisted pairs, diffential measuring, ...  

[StevenD]

I looked up freewheeling diodes, or flyback diodes. I don't think they will help in this application. The spike I am seeing I believe is real pressure spikes caused by the pressure regulators we are using use solenoid valves (both an inlet connected to higher pressure, and a vent to atmosphere). So the cause of the spike is not electrical, but the brief period where the valve connected to the higher pressure is open. I don't have a detailed analysis of the pressure at every point, but from what I am seeing I believe the pressure near the regulator spikes as it tries to equilibrate with the connected pressure, and the outlet pressure, then drops off as the pressure wave travels to the rest of the system.