Zero basis to learn PLC manual drawing for input and output wiring -

PLC( Programmable controller) Is a combination of hard and soft door technology, because we need external wiring programs written to achieve, and not only wiring program of PLC is no meaning, so, introduction to learn PLC must correct the idea, when the PLC is not just programming, also includes the peripheral circuit of PLC.

PLC wiring can be divided into two parts, one is the power supply wiring, one is the IO wiring, the power wiring is very simple, confirm PLC power supply, the PLC on the market are generally two kinds of specifications of the power supply, DC24V and AC220V, before connection, make sure the power of the PLC, otherwise it is a burst of smoke, and general PLC power supply part will have logo, specific can refer to the hardware manual. General PLC boxes will have a simple description, it is important to note that the ground wire must meet, cannot be omitted.

IO connection is PLC of the focus of the PLC input and output wiring, it includes digital and analog. From the perspective of application, the PLC input, is people to the command signal in the PLC. These commands through a variety of switches, buttons, limit, temperature sensor, potentiometer, etc.

first explain the amount of digital connection, it contains the PNP and NPN two forms, actually very simple, you can according to the manual, but many beginners don't have the patience to see the manual, it is not right. The difference between the two connection mode is to the public is not the same as the connection. PNP is also called the logic, the source type connection, high level effectively. NPN also called negative logic, leakage type connection, low level effectively.

beginners how to understand the input signal of PLC, and the NPN and PNP logic connection and implementation?

as shown in the above, this is schneider PLC hardware manual connection that can be seen from the diagram 0 v and sub COM0 end, closed when the switch on the I0, input I0 will have 24 v input, this is clearly PNP connection. So, specific how we are in the actual application, can follow a drawing:

you can see, what is the difference between this and manual? Right, drawings and use PLC DC24V power supply, but the power converter, generally in practice, using this solution, because, when the input quantity too much, or an external wiring is too long, due to the PLC to provide power is low, there may be overloaded, so, all equipped with DC24 V switching power supply.

followed by the field wiring, according to the drawings connected line, then the PLC input part is done.

and the output of the PLC, the PLC is to drive the machine equipment, is to rely on relay, thyristor, transistor to be realized. And this is the three types of PLC controller output. Today, it is to talk about the output of the PLC meaning and how to implement.

PLC output is various in internal circuit, we see as the user is all kinds of terminal blocks.

PLC output

as shown above, the picture on the left of a row of screw is the place where we meet the output, regardless of any PLC is this kind of form, is nothing but different arrangement, screw in appearance. From the appearance, we are unable to distinguish the type of PLC output. Distinguish from models, PLC models generally has said the output characteristics of the letters.

'R' is the abbreviation of English Relay, Relay output, can connect ac/dc load

T is the abbreviation of English Transistor, Transistor output, can only meet dc load

S is the abbreviation of English Silicon, said thyristor output, can only meet ac load

Transistor output can be a high-speed pulse, generally is to control the servo, two connection points NPN and PNP. Thyristor output can be directly connect ac load, seldom used in general. We use most is the relay output, and we usually use the relay is the same. Cost-effective, it can connect ac/dc load, it is just a contact, so regardless of NPN and PNP.

disadvantage is: slow reaction time ( Relative to the transistor) , and has a mechanical life, Transistor is aging, and no life) 。 So, how do we according to the manual wiring? Below I schneider TM218LDA40DRPHN, for example, to everybody from the model, it is a relay output.

PLC manual as shown in figure, this is PLC hardware manual, see the yellow fluorescent pen part, I draw out an output circuit, thus it can be seen that the essence of PLC relay output is a switch, constituted one COM between the client and output terminals of the switch. When Q8 have output, COM and conduction between Q8, will drive the external components, such as relay, lights, etc. And relay to drive motor, frequency converter, cylinder components, such as machine movement.

wiring drawing as shown, this is the actual wiring, red circle part is an external power supply, and yellow fluorescent pen part is Q8 this output circuit. 24 + terminal current from the right into the COM3, when Q8 have output COM3 and Q8 conduction, relay, and host 3 will start, so, the output of the PLC controller is conducting the dots and COM port. Similarly Q9 output is conducting a COM client and Q9, Q12 with output is the conduction COM4 and Q12. It is important to note that the output of the PLC has more than one COM public end, be sure to distinguish between use.

summary: no matter what brand of PLC, are ever changing ca, everybody to learn PLC don't learn to learn, not to learn a certain brand. But master the principle and realization method. So even if we change the brand of PLC, can also be easily mastered. So, still must master PLC from manual to drawing the general formula of hope that beginners can understand seriously, the lines.

In today's world, have risen to an unexpected level of programmable control systems. It has gained a lot of popularity and has come up with different kinds of variations in its content.
Are you looking for more information regarding plc manufacturers plc controller price? Visit Coolmay PLC and contact us as soon as possible!
The manufacturing industry is changing fast, so, for Shenzhen Coolmay Technology Co., Ltd. , being able to pivot and adapt as the marketplace shifts is imperative.