1.6 PRACTICE PROBLEMS
2. A PLC can only go through the ladder logic a few times per second. Why?
3. Indicator lights are used on PLC’s for,
8. What will happen if the scan time for a PLC is greater than the time for an input pulse? Why?
(ans. the pulse may be missed if it occurs between the input scans)
11. What is the difference between a PLC and a desktop computer?
19. Why do PLCs do a self check every scan?
4. TRUE or FALSE -- The test time for a PLC will be long compared to the time required for a simple program.