2014年4月27日星期日

Some of the sequence output module plc

An automatic identification IO modules, IO consecutive numbers down by a physical connection. But the program even without the IO module may still running down. Because IO address is mapped to the cpu's memory, program memory operations generally.
2 software configuration and download it to the cpu to identify the IO module. Once the module occurs from such failure, cpu system plc communication modules  fault alarm can be issued immediately, the hardware must meet the configuration settings, and IO address mapping can also be freely allocated memory space.
I / O expansion bus, there are many, output module plc various PLC manufacturers are different, or look at the refresh rate. Slow, then you can use SPI and the like, and then a little faster, then you can do a physical interface with FPGA, there is one of the fastest Industrial Ethernet.
Simple application can even use the serial port to do. I / O port expansion is the I / O address to the CPU memory map, but  plc logic controller this map is a combination of software and hardware self-identification are defined manually or through assignment and allocation. May be in the exhaust line is whether there should be a line behind the front of the module has a successor in charge of the report module, if the module behind the successor state that level on this line, and when no module is not the same, so that they can be judged No follow-up module, CPU module communicates with other modules using the relay mode, the transmission down a level, that is, only the CPU module and from his recent communication module, output module plc and other modules if you want Communication would have to transit through  plc controller manufacturer other modules, so that modules are installed in accordance with the order of the address of the module can be determined, on power CPU perform a self-test program, each module to report their labeling information so that you can know the total CPU module the number of mounted modules, each module location and type of each module.

2014年4月17日星期四

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

2014年4月15日星期二

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.

2014年4月14日星期一

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.

Select the output module plc switch output module

The output module is required for the internal drive signal to PLC low voltage signal is converted to an external output device. The main selection should consider the type and size of the load voltage, the system latency requirements, whether state and frequent load changes.
1. Select the output mode
Digital output module has three output modes: output module plc relay output, thyristor output and transistor output. Relay outputs are cheap, both to drive an AC load, but also for the DC load, but  Programmable Output Module also for a wide range of voltage magnitude, a small voltage drop, and the ability to withstand strong transient over-voltage and over-current. But it belongs to have contact elements, its movement is slow, short life, poor reliability, and therefore, does not only apply to frequent on-off occasions. When used to drive inductive load, output module plc operating frequency does not exceed its contacts 1Hz.
For frequent load off, you should use triac output or transistor output, they are non-contact components. But only for analog output module  Triac output AC load, and transistor output can only be used for DC load.
2. Select the output wiring of different output wiring of the PLC, are generally grouped outputs and two separate outputs, outputs are grouped several output points as a group, sharing a common terminal between the groups are separated , respectively, using a different power. And each output point delimited output has a common, mutual isolation between the outputs, each output point may use a different power source. The main species Programmable Output Module  should be based on how much power the system load may be. General Integral PLC outputs both groups, there are also separate output.

2014年4月10日星期四

Selection of low-cost analysis of the input module plc

PLC because of its high reliability , simple programming , versatility , small size, compact structure, convenient installation and maintenance , etc. , and in the industrial control has been widely used . PLC modules are generally divided into the following categories : switch input modules , digital output modules , analog input module , analog output modules. Industrial  plc digital input output module control, especially in the field of process control and control need to collect more than analog , input module plc thus PLC analog input and output modules require more, and analog input and output modules are more expensive, increase the analog input and output modules increases the cost and reduces the cost of the entire system , input module plc limit the application of PLC. This paper presents a communication -based analog input and output modules extension method seeks to solve this problem based  Programmable Input Module on analog communication input, output module extension methods
PLC analog input module 12 extend all the way to where the analog input , for example, in the form of an analog signal standard 0 ~ 5V input voltage signal feeding side, the application 12 A / D conversion chip MAX187 analog- digital conversion. MAX187 is a 12-bit serial A / D, has a high conversion rate , the sampling frequency is 75kHz, suitable for high precision here all the way 12-bit analog output , for example, the design will be  plc intelligent controller using 12 D / A converter chip MAX531 to achieve the number of touch conversion. We MAX531 op amp output termination , the analog output is adjusted to 0 ~ 5V, the output part of the hardware circuit shown in Figure 3 . Here , MAX531 is a 12-bit serial D / A, has a higher conversion rate...

2014年4月9日星期三

output module plc connect to 4G network test

In the end how fast network speeds of 4G? Prior to this, have repeatedly reported that several times faster than 3G networks to 4G, output module plc only a few minutes to download several G movies, etc. These  plc digital input output module reports, many of which are advertising in business, few real The person tested and the test results posted for your reference. In Baidu Encyclopedia, also known as 4G systems capable of speeds of 100Mbps download 2000 times faster than dial-up Internet access, upload speed can reach 20Mbps. At present, many of my friends like to watch videos online, I also watch movies with China Mobile TD-LTE 4G network, watch the whole video is  industrial automation plc very smooth, output module plc no obvious lag, the test results show that the speed of 4G is expected to exceed the current 3G network, but the key will have to see after the commercial price. While China Mobile 4G network Declaration on how high rate, but I was in the People's Square, whether on foot or in a moving vehicle test, there will be a few corners no 4G network, which is only a question of my own discovery.
Here I can only say that network optimization is plc analog io module  not achieved overnight, the majority of users are direct witnesses, let us speak with the facts!

output module plc, which has several outputs in the form of general

Common plc output module, which has several outputs in the form of general PLC switch output interfaces commonly used by the output of the switching device, there are three different types: output module plc is a relay output, transistor output and bidirectional thyristor output, output module plc. PLC relay output is to use the relay contacts and coils internal  plc sequence of events recording module circuitry with an external load circuit is electrically isolated from the PLC. Transistor output type PLC via opto-coupler transistor is turned off or turned on allows to control an external load circuit, while PLC internal circuit and transistor output circuit is electrically isolated. Relay outputs can drive AC or DC loads, but the long response time, low operating frequency, but the load capacity of the strongest; while the response speed of the transistor output and bidirectional thyristor output interface, high plc input module  operating frequency, but the former can only be used to drive DC load, which can only be used for AC load. Digital output generally two types: type transistors, relays sex. Analog output generally two kinds: voltage, current type.

2014年4月3日星期四

output module plc introduce some other

Inductance coil , you are fully enclosed inductors , in order to avoid electromagnetic interference between the coils and the coil is enclosed in an iron box, the CPU power supply module is pulse input module plc  used to compensate for current limitations and to provide a stable current to the CPU , safeguard its stable job, it can be initially identified by the motherboard power phase , output module plc has several boxes is several -phase power supply , independent of each phase current power supply provides all the way , because the CPU is a high- power hardware into multiple power power lines can reduce the burden on every road , output module plc reduce the heat every road in order to have better stability in CPU overclocking or running, it 's the number the better , because there is a large current through the plc input output modules  high temperature is normal, as long as your computer using a no-show, do not ignore the problem , which is why high-end motherboard on which you want to increase the heat sink block and Northbridge heat pipe and connected , you can add . That is the cpu power supply modules, three on a 3 -phase power supply , said cpu , high-end motherboards come with yo radiator at the top, there is no low-end motherboard heatsink is exposed . Best to make  plc modular your cpu fan blowing where , if it is not on the blow does not matter. Should not burn unless your motherboard is the second line of low-end motherboard.

2014年4月2日星期三

Numerical plc IO module reads always changing, what is the reason

Roughly divided into the digital input DI, digital output DO, analog input AI, analog output AO. Digital inputs and outputs are generally of 24V. Class 2 4 kinds of analog quantity, category 2 are voltage-and current-mode. There are 0-10V Voltage and -10 to 10V. Current  plc communication module type mainly 4-20MA ,0-20MA. plc IO module and the module through the A / D converter to convert analog into digital +32767 to -32768 between then under control. If there is an alarm relay on the meter, then set the alarm temperature on the instrument, the output relay is directly connected to the digital inputs plc and public clients. If there is no alarm relay on the meter (meter is no such general alarm relay), direct access to analog values ​​plc to make their  plc analog input module own alarm in the program. And direct access to the analog case plc, and because plc and instrumentation wiring different models differ, analog signal inputs can be 4-20mA, it can be 0 - (5) 10V, can also be thermal resistance and the like, the situation is more, the need for specific models can be. Potentiometer is actually sliding rheostat, string a fixed value resistor, calculate resistance. If you do the experiment, find a 24v power supply, and then take analog output module  the fixed value resistor voltage or voltage across the potentiometer input into the AI, they have to be considered a good range. I remember before the first experimental range card transferred to the correct location. The best add isolation (barrier like), to protect AI point.