I have come across an intermittent open sensor alarm used on liquid level sensors for hussmann protocols. Not sure the make of the sensor off hand. I heard when the liquid stacks up to full or goes down to zero these sensors can just go into short sensor or open sensor scenerio.
Ofcourse every time i'm there and graph it its reading and the graph history is normal. But doesn't the graphs log after every 3 min intervals, so if something would spike for a spilt few seconds it would not show on the graph anyways? ya know what i'm trying to say i hope.
kinda lost right now or just to damn burned out to think