Views: 54 Author: Site Editor Publish Time: 2021-08-02 Origin: www.landkinggroups.net
The basic idea of "cabinet air conditioner + heat exchanger" cooling is to make full use of the cooling capacity in the outdoor air and cool the machine room by means of heat exchange. Only the cooling capacity of outdoor fresh air is used, and the indoor air is cooled by heat exchange and then sent back indoors. The heat exchanger is linked with the cabinet air conditioning equipment through the control system. When the outdoor temperature is too high and the fresh air cannot meet the purpose of discharging all cooling loads, the cabinet air conditioning equipment will start automatically to ensure that the internal temperature of the cabinet is within the normal range.
Air conditioning:
Voltage: 220V AC/50Hz
Main control board: circuit board in air conditioner
Auxiliary control panel: control panel in heat exchanger
Heat exchanger:
Power supply: - 48V DC
(1) Air conditioning and heat exchanger function when system works normally
When the temperature inside the cabinet rises to 25 ℃ and the temperature outside the cabinet is lower than the temperature inside the cabinet, the main control board outputs the switching value signal to the auxiliary control board, the heat exchanger starts to work, and the fan speed of the heat exchanger is adjusted according to the preset temperature and speed ratio.
If the fan speed of the heat exchanger has run at full speed and the temperature in the cabinet continues to rise, when the temperature in the cabinet reaches the starting point temperature of the air conditioner, turn on the air conditioner and start refrigeration; At this time, if the temperature outside the cabinet is still lower than the temperature inside the cabinet, the heat exchanger continues to work.
When the temperature outside the cabinet is higher than the temperature inside the cabinet, the main control board sends a signal and the heat exchanger stop working. When the temperature outside the cabinet is lower than the temperature inside the cabinet and lasts for 180 seconds, the heat exchanger starts again.
When the temperature in the cabinet does not reach the starting temperature point of the air conditioner, the fan in the air conditioner also stops running.
(2) Air conditioning emergency operation when encountering heat exchanger’s failure
When the heat exchanger fails or the - 48V power supply fails, and the temperature in the cabinet rises to the starting temperature point of the air conditioner, the air conditioner will be put into operation automatically.
(3) Heat exchanger emergency operation when encountering air conditioning’s failure
In case of power failure or failure of the air conditioner, the air conditioner cannot give the working signal to the heat exchanger, causing the temperature in the cabinet to rise to 40 ℃, the heat exchanger will automatically enter the emergency operation state, and adjust the fan speed according to the predetermined temperature and speed ratio according to the temperature in the cabinet.
(4) Heating
When the main control board measures that the temperature in the cabinet is lower than 5 ℃ and lasts for 300 seconds, the fan in the air conditioner starts and turns on the electric heating. When the temperature is 9 ℃, the electric heating stops working.
When the air conditioner has refrigeration or circuit abnormality, it is output through dry contact alarm;
The dry contact alarm signal is given when the heat exchanger fails;
When the temperature in the cabinet is higher than 40 ℃, the heat exchanger outputs dry contact signal;
You can view the alarm content through the upper computer.
| Refrigeration model / Pros & Cons | Pros | Cons |
| Cabinet Air Conditioners | ● Since the cold air is directly sent near the heat source, it can ensure that there are no hot spots in the cabinet and prevent dust, moisture and corrosive gas from entering the cabinet. It is suitable for the temperature and humidity control of the communication cabinet with high reliability and is a powerful guarantee for the reliable operation of the electronic control system; ● Special heat exchanger is adopted, with large heat exchange, low wind resistance, solid overall structure, dust, oil and corrosion resistance; ● Use the cooling medium without fckw (Freon), which is environmentally friendly, energy-saving and efficient; ● The exquisite patented quick installation fixed structure makes the installation process simple and fast; ● The remote automatic intelligent monitoring system can conduct on-line monitoring and interactive control on the field information of cabinet temperature control at any time; ● Higher protection level (meeting the requirements of national standard internal IP55 and external IP34) improves the safety and reliability of the cabinet; ● There are wall mounted, semi embedded, fully embedded, overhead and other installation methods to meet the customer's on-site use needs. | ● High energy consumption. |
| Heat Exchanger | ● Unique high-efficiency parallel flow heat exchange core with superior heat exchange efficiency; ● The closed circulating cooling system is designed to isolate the internal and external air and effectively isolate the pollution sources in the external air; ● There will be no condensation inside the cabinet due to supercooling; ● Free and flexible installation mode: the unit has different sizes and various installation modes. One machine can be used for multiple purposes, and can be wall mounted, embedded and overhead; ● Compact and lightweight appearance, no filter screen design, reduce cost and no regular maintenance; ● Simple installation, it can be used after the power is connected, the panel is easy to disassemble, and all components are easy to maintain; ● Designed for continuous operation day and night, with strong adaptability and stable and reliable operation. | ● High environmental requirements, it is only applicable to some areas with low ambient temperature throughout the year. |
| Single Temperature Control Mode of Fan | ● Installation of fan for cooling is simple and convenient, with low energy consumption and low cost | ● Unable to bear the heavy responsibility of cooling the cabinet for a long time, with low reliability and stability; ● With the passage of time, dust and other dirt are easy to accumulate and pollute the components in the cabinet, thus aggravating the heat island effect. |
| Integrated Unit of Cabinet Air Conditioning and Heat Exchanger | ● The unique dual unit system of heat exchanger and cabinet air conditioner is adopted, which has high reliability, especially suitable for the communication industry; ● Two sets of independently controlled refrigeration systems can work independently or simultaneously in different temperature environments; ● The power saving effect is obvious, generally more than 40%; ● Relatively reduce the working time of cabinet air conditioner, so as to prolong its service life and reduce the investment cost and maintenance cost of machine room; ● It has the functions of environmental monitoring and remote control; ● Wide application range. | ● No obvious shortcomings. |
Integrated Unit of Cabinet Air Conditioning and Heat Exchanger is obviously superior to simple cabinet air conditioner, heat exchanger, fan and other single cooling forms, which are better reflected in improving temperature control efficiency, reducing energy consumption, prolonging equipment service life and expanding application scope.
