We want to use the timer logic to satisfy the rest of the second program requirement. The oil pump should stop if the Ball Mill motor stops when it has been running less than 20 seconds, but the fan should run an additional 5 seconds.
We will take advantage of the properties of a Timer Off instruction to make this happen.
We will look at the third specification for the program:
"If the Mill has operated for more than 20 seconds, the fan should remain on until reset by a separate fan reset button, and the oil pump should remain on for an additional 10 seconds after the Mill is turned off."
We will program the log...
The fourth program requirement requires if the Mill motor temperature goes above 80 degrees C, the mill should be stopped to protect the windings.
The input from the temperature transmitter will need to be scaled to produce a value in engineering units, in this case, degrees C.
The “SCALING” in...
The final program requirement defines the conditions for which three stack lights should be set.
In each case, the feed flow rate to the Ball Mill is used to determine the light status.
The green stack light should be set if the flow rate is between 20 and 75 pounds per minute.
The red stack ...
