SteelBlue48310 Posted February 20, 2013 Report Share Posted February 20, 2013 OK, new problem to solve... I am really stumped trying to solve a logic issue with my M91 project. Here's the scenario: I have an analog transducer that is mechanically tied to a piece of machinery that moves in a linear motion. (Up and down) The M91 shows the relative distance from the floor, in inches... and I can set a 'new' height value which causes an output to energize that closes a motor contactor to run a motor to move the machine up or down. That part all works great. What I am struggling with is the logic to display a message in the event of a failure to actually move the machine, for a variety of reasons. The hard part is that the machine moves *very* slowly, and can take as much as 10 minutes to move from the lowest point to the highest point.... but, I want the 'failure' message (display) to occur if there is no actual movement within 5-10 seconds. With the 'math' and 'compare' functions that I have available to me in the M91 ladder, I can't seem to find the "right" methodolgy to make this work! Any ideas would be greatly appreciated! ~Mike Link to comment Share on other sites More sharing options...
SteelBlue48310 Posted February 21, 2013 Author Report Share Posted February 21, 2013 Got it working... I used a 'direct store' of the current value of the analog input, and then compared that to the new input and fired a 5 second timer if they were different. Just had to think a bit more! Link to comment Share on other sites More sharing options...
Cara Bereck Levy Posted February 25, 2013 Report Share Posted February 25, 2013 Great :-) Link to comment Share on other sites More sharing options...
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