Introduction to Industrial Automation

Example 4.3:  Machine Operation by Pushbuttons and Sensor

To investigate the previous remark further, let’s consider the case of a machine that contains two 

direct on line starting motors being supplied by power through the relays C

1

 and C

2

. The first motor 

(C

1

) is being controlled manually through the utilization of two pushbuttons, b

0

 for STOP and b

1

 

for START. The second motor (C

2

) is being controlled from a sensor s. Moreover, in this automation 

b

1

+f

1

e+b

0

+f

0

C=0

C=1

Figure 4.7  State diagram for the direct on line starting motor with thermal overload protection