28 Which of the following devices can be used for switching

28. Which of the following devices can be used for switching                28.

     the output of a discrete DC output module?

     a) Transistor.       c) relay.

     b) Triac.       d) either a or c.

29. The current sourcing sensor shown in Figure 2-7                              29.

     must be matched with a _____ PLC input module.

a) current sinking.

b) current sourcing.

c) alternating current.

d) either a or b.

Figure 2-7   Current sourcing sensor for question 29.

31. For the block diagram of the analog PLC control                             31.

    shown in Figure 2-8, which part has a binary

    input and analog output value?

     a) Level transmitter       c) Processor

     b) Input module       d) Output module

Figure 2-8   Block diagram for question 31.

Solution

28) either a or c

29) current sinking

31) output module