Refrigeration controllers
The HVAC and refrigeration controller is actually an electronic board (microprocessor) that is configured for a specific application and adjusts parameters base on specific algorithm till remaining set point considering its digital and analog inputs. Digital inputs include a variety of on-off switches and analog inputs include the outputs of sensors.
Construction of refrigeration controller
Generally, the controller consists of three main hardware parts: inputs, outputs, and power supply.
Digital and Analog inputs:
In a HVAC and refrigeration controller, the inputs are divided into two main types, digital and analog. Digital inputs indicate the position of a switch or contact in the open or closed state (on/off). These types of inputs are usually used for alarms, on-off system, or changing a specific position. Other one is analog inputs. Analog input specifies the instantaneous value of a parameter and is applied for measuring parameters such as temperature, pressure, humidity, etc.
Digital and Analog outputs:
This section includes digital outputs (relay output) and analog outputs. In the HVAC and refrigeration controller, digital outputs or relay outputs are used to issue commands to disconnect and connect the compressor, fan, heater, pump, alarm, and others. Analog outputs are used to momentarily increase or decrease a parameter based on the values received from the analog inputs. For example, increasing or decreasing the speed of the fan based on changes in ambient temperature. Of course, other outputs may be installed on the controller to connect to the PC or network.
Power supply
The power supply of refrigeration controller can be 12Vac/dc, 24V ac/dc, or 220Vac according to models and brands.
Types of refrigeration controller
According to the application, that controller is used for it, they can be classified as parametric and programmable one.
Parametric refrigeration controller
This type of HVAC and refrigeration controller is designed for a specific application and it is not possible to change their configurations. There are many types of this refrigeration controller for different application, such as: refrigerators, chillers & heat pumps, cold rooms, freezers, compressor racks, blasters, etc. The alarms and configuration of these types of controllers are completely in accordance with their usages and the specific items and details of the application are configured on them. Digital thermostats can be named as the simplest type of a parametric controller.
Among the best parametric refrigeration and HVAC controllers we can mention Dixell iCHILL evo series IC200 models, iProCHILL series models like IPC115D and IPC315D for chiller, heatpump, condensing unit and rooftop applications, iProRACK series for compressor racks and iProAHU for standard and advanced air handling units.
Programmable refrigertion controller
Programmable HVAC and refrigeration controller is one of the other types of controllers. These controllers do not have default software and the user is able to prepare the various applications software and install on it. Most popular programable controllers in refrigeration and HVAC fields can be mentioned Danfoss MCX controller series models, Dixell iProGenius series and Carel pCo controller series.
Aljebal, supplier of all Danfoss MCX, Dixell iCHILL and iPro and Carel refrigeration and HVAC controllers in Dubai, UAE.
