Bayden Smith

Thanks John, That is perfect and gives me exactly what I am after. I was already making them toStep() so I wouldn't get a join the dots line, but was unaware of the '30d' part of that formula. Regards, Bayden

I am trying to do analysis of various process variables against their setpoints. I do this by trending the various variables along with setpoints. Some have calculations to determine differences or sometimes multiple setpoints are needing to be added to get a final setpoint. When I add the setpoint signals, some will not display unless they have changed in the viewing window due to the infrequent data points. I can increase the maximum interpolation but this still only works if there is a change in the viewing window (but does give me the line back to the previous change). Since each setpoint can change multiple times a day or remain constant for weeks at a time this makes this difficult to use reliably. I can always use a fixed value but then I will need to change it when the setpoint changes and is not workable on a live trend. I can replace invalid values with another one which works, but this is the same issue as using a fixed value in that it will not necessarily be the correct value for a live trend. Is there anyway to get around this limitation?