PLC IO module and the electrical circuit

The pace of work from the vibration signal control. The operation is used for digital or logic operation, under the command of the controller work. Register to participate in operations, input module plc and to store intermediate results of operations, it is under the command of the controller.

CPU speed and memory capacity of PLC is an important parameter, which determines the pace of work PLC, IO number and software capacity, limiting the size of control.

PLC and the electrical circuit is through the input and output interface, complete the part (I/O). The IO module plc  integrated circuit PLC, the input registers to reflect the state of the input signal, the output reflects the state of the output latch.

PLC IO Modules

In 2010 and 2011, after years of double-digit growth of the recession, I / O module market started to recover, especially programmable controller module plc. However, the recovery of a distributed control system (DCS) I / O bit slow marketI / O
Modules, most of which is used with the controller, is an important part of complex industrial automation systems. By adding more IO module plc, the scope and flexibility of the entire automated system can be improved. PLC, for example, can move towards their ability to control the field level to increase the remote I / O modules. There are many active in this market suppliers, including a full range of automation products and expert mainly provides cpu module suppliers

Input module plc

PLC input module is the A / D converter module, with four independent analog input channels, output module plc signal for each channel can be 1 ~ 5V voltage signal can also be 4 ~ 20mA current signal. plc digital input module can input signal into a binary digital signal corresponding to eight, i.e. the measurement accuracy or resolution is eight of said. Decimal representation, it is converted into a value ranging from 0 to 255, provided to the PLC for further processing.
On the side of the module, corresponding to each plc ethernet module channel has a jumper, the user can be selected by shorting or jumper pins measuring not less then access signal is 1 ~ 5V voltage signal, or 4 ~ 20mA current signal. Signal conversion module, the maximum time is 2ms, the signal converter is working in parallel with the CPU of the PLC, the PLC scan time is not occupied.

Output module plc

Power amplifier components output module plc has a high-power transistors and FET driven DC load, triac drive AC loads, and both can drive an AC load and can drive a small relay DC load. Output current is typically 0.3 ~ 2A, load power is provided by an external field.
Relay output circuit. Internal circuit relay coil is energized, its normally open contacts closed, the external load electrical work. Meanwhile relay from isolation and power amplification, each way just to provide a pair of normally open contacts. And contact parallel RC circuit and varistor to eliminate Tun arc generated when the contacts open, in order to reduce the interference of its CPU.
Is the transistor collector output circuit. . plc communication module to the internal circuit output latch, and then the optical coupler to the output transistor, which saturated conduction state and an OFF state corresponds to turn on and off contacts. Figure regulator to suppress external shutdown and overvoltage surge voltage to protect the transistor, the transistor output circuit delay time. Structure and the transistor output circuit FET communication modules plc is substantially the same.

How to select plc IO module manufacturers

Domestic production plc IO module manufacturers are said to have many thousands, how can choose their own power supply module manufacturers do?
1, for the size of their own requirements. Some foreign brand quality is really good, but the price is not every user can programmable plc  accept, plc IO module and delivery compared to domestic brands, is very long. For some of the larger domestic supplier of power modules also have this problem, if you set its main ship models of non-models, delivery is also not guaranteed. If you own custom made a special power, for small customers, is simply unthinkable. Because SMEs did not like Huawei, ZTE delivery platform choice, to choose their own scale enterprises, is very important. VST such as power companies, specifically for SMEs to provide power solutions, to provide customized services.
2, plc IO module product line to see the  plc temperature control module situation. Such as power modules, it can provide as a half brick, 1/4 brick, 1/8 brick, 1/16 brick industrial products such as can not provide, explain corporate R & D strength and size is small. The ability to customize the product, whether it can provide a wealth of customized products, customized experience like railways, electricity, military areas or very important. Look material. Open a module power, their own look, workable than listen to others. Material from the supply of products, we can see that the quality of power supply manufacturers and positioning, choice of materials, like the Programmable Input Module  power to see the materials. Open a module power, their own look, workable than listen to others. Material from the supply of products, we can see that the quality of power supply manufacturers and positioning, choice of materials like power

output module plc 's product positioning and product characteristics

Use output module plc saving can be considered to contribute to the cause of environmental protection ! Now the market needs the power module also needs to pay attention to it from the environment.
    Switch output module plc products for the  industrial automation plc point system to contribute to a low-carbon society , and now the market demand began to increase , and it requires a smaller size, lighter weight and higher efficiency and less power consumption , lower output power and no-load conditions . In such a market demand , the development of compact, light weight, high efficiency power supply open frame peak power capability . They offer a wide operating temperature range , to ensure that poor working conditions , excellent output level , smaller size and lighter weight of up to 30% compared to existing models , safe operation. Thus, they can make products smaller customers and help develop energy-saving products . In addition , the plc temperature control module  existing lineup with a wide range of input power factor and harmonic correction helps to reduce energy consumption by a significant reduction in energy-saving equipment size and weight that the product positioning of the power module and product characteristics , the more fully explain the power modules it.if the power supply in harsh environmental conditions , the output DC voltage plus the output transient voltage after the noise is still able to maintain a stable the output voltage does not exceed plc input output modules  the limits of the output voltage level of the situation , otherwise may cause the supply voltage exceeds or falls below a logic circuit ( such as TTL circuits ) is exposed to the power supply voltage malfunction, causing further freezing.

input module plc introduced in the DC chopper

DC / DC converter is a variable DC voltage into a fixed DC voltage , also known as a DC chopper . Chopper work in two ways , first pulse width modulation Ts constant change ton ( GM ), input module plc Second, frequency modulation (
(1) Buck circuit - step-down  intelligent plc chopper , the output average voltage less than the input voltage U0 Ui, of the same polarity .
(2) Boost Circuit - boost chopper , the output voltage U0 is greater than the average input voltage Ui, the same polarity .
(3) Buck-Boost circuit - a buck or boost chopper , the average output voltage is greater or less than the input voltage U0 Ui, of opposite polarity , inductive transmission. 4) Cuk circuit - a buck or boost chopper , the average output voltage is greater or less than the input  programmable logical controllers voltage U0 Ui, of opposite polarity , capacitance of the transmission . There Sepic, Zeta circuits. input module plc above non-isolated DC-DC converter circuit , isolated DC-DC converter circuit has a forward , flyback , half-bridge circuit , full bridge circuit , push-pull circuit .
Soft-switching technology makes plc intelligent controller  today's DC / DC undergone a qualitative leap , the maximum output power 300W, 600W, 800W , etc. , the corresponding power density (6.2,10,17) W/cm3, efficiency ( 80 to 90 ) % . The switching frequency (200 ~ 300) kHz, the power density has reached 27W/cm3.