List six distinct advantages that PLC offer over conventional relay based control system. List four criterions by which PLCs are categorized. Draw the PLC block diagram. What are the two most common types of PLC programming devices? What is the standard programming language used with PLCs? Following each question contain 2 points. PLCs were originally designed as replacements for: microcomputers, analog controllers. relay control panels. digital controllers. Which of the following is not an advantage that PLCs offer over the conventional relay-type of control system? Smaller size Higher current capacity Less expensive More reliable The central processing unit: looks at the inputs, makes the decisions based on the program, and sets the outputs. looks at the outputs, makes the decisions based on the program, and sets the inputs. serves only to store the program in memory. serves only to supply power to the backplane. The output interface module connects to: sensing devices such as switches or pushbuttons. load devices such as lamps or solenoids