Controllers are important devices for the efficient operation of technology. How did they come about? Where are they used? What in general terms does their installation, connection, setup, repair and replacement of the controller look like? Answers to these questions will be given as part of this article.
What are controllers?
This designation in automation systems is used for devices that are entrusted with the functions of controlling physical processes according to a previously recorded algorithm. In this case, information is used, which comes from the sensors and is output to the actuators. In computers, controllers are devices that connect peripheral devices to internal data pipes . Thanks to processing slow I / O operations, their operation has a positive effect on system performance. That is, controllers are devices that sort out part of the functionality of the central processor. So, he no longer needs to constantly listen to whether the keyboard is active or not. The tasks of the central processor only include the willingness to accept data about the presence of interaction and react accordingly to it.
History of occurrence
For the first time in industry, they were used for building cars in the late 60s. They were used to automate assembly lines. Computers were then very expensive, so the controllers used tough logic that was programmed in hardware. But their reconfiguration was a very time-consuming process. Therefore, there were devices that changed using a special relay. They were called
programmable logic controllers, and it has survived to this day. Over time, devices arose that were programmed in machine-oriented languages. This is easier to do constructively, but you must have a programmer to make even the smallest changes to the control algorithm. From that moment on, the process tasks were constantly simplified. First, high-level languages arose, and then special
visual programming, which has much in common with relay logic.
Application
You can find controllers almost everywhere: in the automation of technological processes, in machines with numerically-programmed control, in alarm and emergency protection systems, life support, building life support, security, communications, in medical and experimental equipment. Despite this spread, there are still quite a few areas where these devices are just starting to appear.
We do the installation and replacement
How are controllers installed? For simplicity of explanation, and also considering the large number of possible applications, we will consider a specific case with a device that deals with the temperature in the greenhouse. So, initially we will need to choose the installation horizon. As a rule, the mid-height of adult vegetation is selected in its quality. Care must be taken of the mounting location. Certain requirements are put forward to him. So, it should be in a place where air circulation will be at least relatively carried out. In addition, there should be direct free access to the temperature sensor so that nothing creates interference. Then the controller is installed directly, it is mounted in its place, and it remains to connect, configure and use its services. And what if there are problems with the hardware component of the device? Replace if necessary. We'll have to disassemble the device and reassemble the entire temperature support circuit, focusing on the physical characteristics of the new device.
Connect
To power the controller, there are two main options:
- Stationary energy source. This implies the presence of a battery that will supply energy to the controller. The advantages of this option include a significant level of autonomy. But in this case, the controller battery should be charged regularly. You can automate this process by developing a circuit that will connect it to the network. When the charge is less than a certain value (say, 50%), then recharge will be included. But this is an additional waste of energy (albeit not very significant).
- Circuit. This implies connecting the controller to the power grid. But if you need to control the temperature constantly (in a greenhouse with exotic plants or an incubator for chickens), then because of the possibility of loss of current, this option is not suitable. You need to weigh the pros and cons of each scheme.
Customize
Everything is pretty simple here. The controller just needs to be set to the required temperature range and actions during its transition. If we talk about the purchased device, then interfaces should be provided in it, by working with which you can do everything you need. With homemade appliances it will be a little more complicated. You can select the required temperature in the greenhouse by adding new elements or changing the values already set. In this case, you should watch so as not to accidentally burn the circuit due to overload or to put in a part that will make it insensitive. For this, it will be necessary to make the appropriate calculations and make sure that they are correct, in practice. That's the whole controller setup.
Repairs
When controllers fail, there are three main options:
- Tell professionals to repair it.
- Throw it away and buy a new one.
- Repair yourself.
Each of them is costly in its own way. So, the first two rest mostly on money, and the third in their own time and effort. And if the factory controller fails, then it’s better not to try to figure it out on your own (although in the end it all depends on the desires and confidence in one’s own skills). Repair yourself is best suited in cases where the device was own and assembled. In this case, it will be necessary to use special equipment (or test circuits) and establish the operability of each element. And when a broken link is revealed, it will need to be removed and a new part installed in its place that has no problems with functioning. That's the whole do-it-yourself controller repair. There is nothing complicated for the master.
Conclusion
As you can see, controllers are not complicated. The same can be said about the processes of working with them. But you must remember that controllers are devices that operate under a certain voltage, so you should be careful. The best option would be to place the device in a shell, due to which access to it by unauthorized persons will be significantly limited.