Introduction to Industrial Automation

Figure 10.22  Color-based separation of plastic balls.

M

ENC

SHM

PLC

I1.0

Inputs

Outputs

50 cm

100 cm

Q4.0

Q5.0

Q6.0

I1.1

I2.1

I2.2

I3.0

+24 V DC

+24 V DC

SS

1–2

Start

Stop

ENC

0 V

0 V

C

1

C

2

C

3

M

M

SHM

Figure 10.23  Shearing machine of an unfolded aluminum sheet.

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402

 

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  Introduction to Industrial Automation

10.24   Inlet and Outlet Rate Monitoring of Transferred 

Objects In and Out of a Process Machine

The transportation system of a processing station, which includes two independent conveyor belts 

M

1

 and M

2

, is shown in Figure 10.24. The first conveyor part inserts objects in the station and 

the second part removes the processed objects. Two sensors PS

1

 and PS

2

 detect the incoming and 

outgoing items respectively. Write an automation program so that the PLC stores the current 

counting of processed objects, based on what will regulate the operation of the transportation 

system and specifically:

  1. The conveyor belt M

1

 starts to operate via the switch RS

0-1

.

  2. If there are objects, one or more, in the processing station, then M

2

 also operates.

  3. If there are more than five objects inside the station, then the M

1

 stops, and starts automati-

cally again when objects become less than five.

  4. If there are no objects in the station, then M

2

 stops.

  5. If the conveyor M

1

 has stopped for a period exceeding 30 s, then the current counting is 

zeroed, considering that in the existing station the objects have been destroyed.

  6. With the switch RS

0-1

 open, both conveyors stop.