Control systems
Control systems can be divided into four categories:
- Controls that make the system safe.
- The controls needed for the proper and efficient operation of the system.
- Controls that provide favorable conditions in air-conditioned comfort or product are saved.
- Controls that allow to optimize the operation, for example. provide the necessary cooling with minimum energy.
Safety standards and codes, such as EN378 provide certain safety requirements depending on the type and size of the installation, and some of them, such as high pressure cut-out switches will be self-Executive and independent of any control system. Where appropriate sensors, control system, it is highly likely include additional security elements, which are activated to any local cut.
Proper exploitation includes, for example, to the fact that the compressor operates within the allowable working conditions and adequate oil pressure. Protection devices such as these are not necessarily safety critical, but will help to ensure reliability of NPP.
Effective work may require that some compressors turned off instead of running multiple compressors with partial loads. This type of sequence, as a rule, be included in the base controller.
There are two types of devices that report on the conditions. These sensors and detectors. Sensors output variable according to the value which they measure. On the contrary detectors give only the presence or absence of a signal.
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Air-Conditioning