Introduction to Industrial Automation

139

SECOND SOLUTION BASED ON THE COMPONENT 

STATE DIAGRAM METHOD

The digital components of the system are the two motors M

1

 and M

2

, and the timer T for measuring 

the delay time of 20 s. Therefore, the components states of the system are, {C

1

 for M

1

}, {C

2

 for M

2

}, 

and {C

3

 for T}. The component state diagram is shown in Figure 4.27, where the transition to states 

C

1

 and C

2

 is triggered simultaneously by the instant start signal “x” from a button. The signal “T” is 

produced by the timer T, the activation of which happens on state C

3

 by the instant stop signal “s” 

from a button. The deactivation of state C

2

,

 

due to signal T, triggers subsequently the deactivation of 

state C

3

, or in other words the turn-off of timer T, since there is no longer a reason to operate.

Μ

1

Μ

2

Figure 4.25  A metal drilling and milling machine tool with two different processes in terms of