CHAPTER 2 ELECTRICAL Pneumatic CONTROL

　

　

中文         Orang indonesia 

　

2.1 Preface         

             Electric Pneumatic control is the use of a control circuit composed of general electrical components and a pneumatic circuit to form an electrical Pneumatic control system. The use of the circuit system is low in cost, convenient in wiring, simple in design, and features such as delay, counting, memory, and interlock , Can achieve more convenient and effective control.

　　      In the circuit diagram of the electric pneumatic control system, there will be a ladder diagram of the electric control circuit (Ladder Diagram) and a pneumatic circuit diagram . The interconnection between the two is mostly through solenoid valves (Solenoid) and limit switches (Limit Switch) , the reed switch (magnetic the reed switch ) , pressure switch (pressure switch) , such as gas-electric conversion element, in the circuit diagram, respectively, to the SOL , the LS and PS represent the

　　  　The ladder diagram of the electrical circuit, as the name suggests, is like a ladder. The control circuit is connected between two parallel wires. These two parallel wires are the live and ground wires of the electrical control system. All circuits are connected to these two parallel wires. between the lines; on the ladder diagram, Firewire (Hot line) that is marked " + " sign or a " H " of the power supply line, ground line (ground line) was labeled " - " sign, or " G " of the ground line . The components connected to the live wire are mostly switch contacts of buttons, limit switches, pressure switches, relays, timers, counters, etc. The contact components are used for ON/OFF control in the circuit, and the contacts can be connected in series (AND) , Parallel (OR) connection ; most of the components connected to the ground wire are loads, such as solenoid valves, indicator lights, buzzers, relays, timers, counters and other components of the load coil, used in the circuit for load output. The load components can only be connected in parallel , and cannot be connected in series to avoid the increase of impedance and the lack of electric power and loss of efficiency.

　

Indicator circuit

2-1.1 Commonly used electrical components

　

　

PB button, SW finger dial, EMS press button emergency s switch

　

             

　

                   

Double acting cylinder + limit switch

            

             

　

Timer, counter, buzzer, indicator light, relay

     

5/2 double solenoid valve                                           5/3 double solenoid valve

5/2 single solenoid valve

Pressure Switch

Vacuum generator with pressure switch

POWER SUPPLY

Motor control module 1

Motor control module 2

　

       2-1.2  Basic application circuit

?       

       YES circuit

?       The state of output and input are the same. It is often used for starting control of circuits.

　

?       

       NOT circuit

?       The state of output and input are opposite. It is often used to s the circuit.

　

?       

       Series (AND) circuit

?       All inputs are established and outputs are established. Often used for security control purposes.

　

?       

       Parallel (OR) circuit

?       Any input is established and output is established. Often used for multiple input control purposes.

　

?       

       From Paul ( memory ) circuit

?       After the pulse is input, the output signal is maintained continuously through the bypass (BY PASS) of relay a .

       It is often used for circuit output maintaining control.

?              Interlock ( priority ) circuit

?       Use relay b contact to cut off the path of the reverse circuit to avoid the occurrence of simultaneous energization of both sides.

       It is often used for bilateral solenoid valve or motor forward and reverse control.

Motor Control

　

       2-2 Basic precautions         

?

        1. Before operation, adjust the flow rate of all speed control valves to the minimum; reset the timer and counter to zero; and check whether there is water in the three-piece combined filter cup.

            If so, loosen the bolt at the bottom of the cup to drain water and adjust the pressure to .

        2. When  wiring and piping, the power supply and Pneumatic source should be turned off to avoid danger and component damage caused by electric shock or pipe explosion.

        3. When  connecting or disconnecting the circuit, hold the connector end and do not pull the wire , so as not to damage the internal copper wire.

        4. The unused components and pipelines on the machine platform should be placed properly and don't fall to the ground.

        5.  If the power cord is suspected to be disconnected, you can switch the three-purpose meter to the ohm range for measurement; or connect the power supply to the indicator light to confirm.

        6. The power cords should be sorted and neatly sorted according to their lengths , and they should not be tangled or tangled.

            After use, put the power cords of the same length together and put them in place.

        7. When wiring, you should follow the order of the electrical ladder diagram from left to right, up and down , and don’t jump in randomly.

            So as not to cause wiring inaccuracy and increase the trouble of checking the line.

        8. After the Pneumatic and electrical circuits are connected properly, turn on the pressure source and power switch and start the circuit.

            If you cannot move or move incorrectly, turn off the Pneumatic and power switch before making corrections to the circuit.

        9. If there is still no power after turning on the power, confirm whether there is a short circuit. And check whether the overload protection is tripped or the fuse is burned out? 

            If there is a possibility of a short circuit, the power should be turned off first , and the power can be turned on after removing the short circuit and obstacles .

           10. If the same contact appears repeatedly in the loop , separate wiring and avoid sharing terminals to reduce the occurrence of short circuits or error signals. 

                 And pay attention to the order of the wiring of the contacts to avoid short circuit caused by the connection of the live wire (+) and ground wire (-) .

           11. NO normally open contact (Normally Open Contact) that is a contact point

                 ( Usually it is open circuit without power, after switching, it is closed circuit with power ) ,

                 NC normally closed contact (Normally Closed Contact) is the b contact

                 ( Usually it is closed-circuit energized, after switching, it becomes open-circuit without energization ) .

       12. After all the operation is completed, should be closed and the power pressure source and receipt of the pressure tube and the power supply line, cleaning placement table , and indeed fill usage history table .

　

       2-3 Basic circuit           

       2-3-1　single solenoid valve control circuit

      Internship purpose: to understand the operating principle of 5/2 single solenoid valve.

      Use circuit:

       2-3-2　Self-protection ( memory ) control circuit

      Internship purpose: to understand the operation principle of self-protection circuit.

      Use circuit:

       2-3-3　Double solenoid valve control circuit

      Practice purpose: to understand the principle of operation of dual solenoid valves.

      Use circuit:

       A. 5/2 double solenoid valve

       B. 5/3 neutral double solenoid valve

       C.5/3 Neutral Air Intake Double Solenoid Valve

       2-3-4　series and parallel control loop

      Practice purpose: to understand the operation principle of series and parallel circuits.

      Use circuit:

       A. Series circuit

       B. Parallel circuit

       2-3-5　Interlock ( Priority ) Control Circuit

      Practice purpose: to understand the operation principle of the interlock ( priority ) control circuit.

      Use circuit:

       2-3-6　One reciprocating control loop

      Internship purpose: understand the function of memory circuit and limit switch and the application of automation.

      Use circuit:

       A. 5/2 single solenoid valve

       B. 5/2 double solenoid valve

       2-3-7 Continuous reciprocating control loop

      Internship purpose: understand the function of memory circuit and limit switch and the application of automation.

      Use circuit:

       A. 5/2 single solenoid valve

       B. 5/2 double solenoid valve

       2-3-8　Delay control loop

      Internship purpose: to understand the function of Timer .

      Use circuit:

       2-3-9　counting control loop

      Internship purpose: to understand the function and application of the counter (Counter) .

      Use circuit:

       2-3-10　Emergency s homing control loop

      Internship purpose: understand 5/2 emergency s homing control.

      Use circuit:

       A. Single solenoid valve emergency s homing control

       B. Single solenoid valve returns to position after emergency s is released

       C. Double solenoid valve emergency s homing control

       D. Double solenoid valve returns after emergency s is released

        2-3-11　Emergency s and move to the end control loop

      Practice purpose: to understand the function of 5/2 double solenoid valve emergency s moving to the end control.

      Use circuit:

      2-3-12　Single button ON/OFF control circuit

      Internship purpose: to understand how to achieve the function of power switch with a single button.

      Use circuit:

 

       2-3-13　Load balancing control loop

      Practice Objective: Learn how to 2 Ke 5/2 single solenoid valve with the relief valve reaches the intake bilateral attached load balancing function.

      Use circuit:

       A. 5/2 single solenoid valve load balance control

       B. 5/3 dual solenoid valve load balance control

     

       2-3-14 Load lock control circuit

      Practice Objective: Learn how to 2 Ke 5/2 single solenoid valve with bilateral guide intake valve reaches annexed locking function.

      Use circuit:

       A. 5/2 single solenoid valve load lock control

       B. 5/3 dual solenoid valve load lock control

       2-4 Application circuit        

       2-4-1 Double　-cylinder sequential action control circuit

      The purpose of the practice: to use solenoid valve with limit switch and electrical circuit for sequential control of double pneumatic cylinders.

      Use circuit:

       A. 5/2 single solenoid valve sequence control

       B. 5/2 double solenoid valve double cylinder sequence action control

       C. 5/2 single solenoid valve double cylinder sequential action control

       D. 5/2 double solenoid valve double cylinder sequence action control

       E. 5/2 single solenoid valve double cylinder sequential action control

       F. 5/2 double solenoid valve double cylinder sequence action control

 

       2-4-2　Delay sequence control loop

      The purpose of practice: to control the time delay sequence with double pneumatic cylinder solenoid valve, limit switch, timer and electrical circuit.

      Use circuit:

       A. 5/2 single solenoid valve delay control

       B.    5/2 double solenoid valve delay control

        2-4-3　Delayed Repeat Action Control Circuit

      The purpose of the practice: to control the sequence of time-delayed repetitive actions by using double pneumatic cylinders with solenoid valves, limit switches, timers and electrical circuits.

      Use circuit:

       A. 5/2 single solenoid valve time-delay iterative control

       B. 5/2 double solenoid valve time-delay repetitive control

       2-4-4　Counting sequence control loop

      The purpose of the practice: to control the sequence of time-delayed repetitive actions by using double pneumatic cylinders with solenoid valves, limit switches, timers and electrical circuits.

      Use circuit:

 

      2-4-5 single solenoid valve three-cylinder sequence action, delay, emergency return loop

      The purpose of the practice: to use three pneumatic cylinders with 5/2 single solenoid valve, limit switch, timer and EMS emergency s button for sequential action, delay and emergency return control.

      Use circuit: 

       2-4-6　Double solenoid valve triple cylinder sequence action reverse sequence return circuit after emergency s

      Internship purpose: Use three pneumatic cylinders with 5/2 double solenoid valves, limit switches and EMS emergency s buttons to do sequential actions and reverse sequence return control after emergency s.

      Use circuit:

 

              2-4-7　Single solenoid valve three-cylinder sequence action emergency s return circuit

      The purpose of practice: To control the sequence delay action with three pneumatic cylinders with 5/2 single solenoid valve, limit switch and electrical circuit.

      Use circuit:

 

      2-4-8 Double solenoid valve triple cylinder sequence action emergency s stroke to the end to continue action control circuit     

      The purpose of the practice: Use three pneumatic cylinders with 5/2 double solenoid valves, limit switches, and electrical circuits for sequential actions to continue the action control after the emergency s stroke is released to the end.

      Use circuit:

 

       2-4-9　Single solenoid valve three-cylinder sequence action emergency s synchronous homing control loop

      The purpose of the practice: use three pneumatic cylinders with 5/2 single solenoid valve, limit switch and electrical circuit for emergency s synchronous return control.

      Use circuit:

                 2-4-10  double solenoid valve three cylinder timing control circuit

      The purpose of the practice: use three pneumatic cylinders with 5/2 double solenoid valves, limit switches, timers and electrical circuits for timing control.

      Use circuit:

 

       2-4-11　Single solenoid valve three-cylinder sequential action circuit

      The purpose of the practice: to control the sequence action with three pneumatic cylinders with 5/2 single solenoid valve, limit switch and electrical circuit.

      Use circuit:

       2-4-12　double solenoid valve three cylinder counting control loop

      The purpose of practice: to use three pneumatic cylinders with 5/2 double solenoid valves, limit switches, counters and electrical circuits for counting control.

      Use circuit:

         

       2-4-13　Single solenoid valve three cylinder counting sequence action circuit

      The purpose of the practice: To control the sequence counting action with three pneumatic cylinders with 5/2 single solenoid valve, limit switch, counter and electrical circuit.

      Use circuit: 

　

       2-4-14　three-cylinder two-stage non-return action circuit

      The purpose of the practice: Two-stage non-return sequence action control with three pneumatic cylinders with 5/2 single solenoid valve, limit switch and electrical circuit.

      Use circuit:

[1] Relation between switching signal and touch: the touch and signal switching relationship between the pneumatic cylinder and the roller valve during the movement stroke.  

       Taking A+B+B - A - as an example, the diagram of the relationship between the switching signal and the touch is as follows:

　

[2] Displacement - time graph: A graph indicating the action state of the pneumatic cylinder. In the figure, the horizontal axis is time, the vertical axis is displacement, and the slope is speed.  

       Take Aslow+B+tB - A - as an example, the B cylinder is slow out and fast back, and the displacement - time diagram is as follows:

　

  

END