4. Develop a FBD for a system that will monitor a high temperature salt bath. The systems has start and stop buttons as normal. The temperature for the salt bath is available in temp. If the bath is above 250 C then the heater should be turned off. If the temperature is below 220 C then the heater should be turned on. Once the system has been in the acceptable range for 10 minutes the system should shut off.
6. Write a structured text program that reads inputs from ‘channel 0’. An input string of ‘CLEAR’ will clear a storage array. Up to 100 real values with the format ‘XXX.XX’ will arrive on ‘channel 0’ and are to be stored in the array. If the string ‘AVG’ is received, the average of the array contents will be calculated and written out ‘Channel 0’.