For Telecom enclosures and shelters Application Guide Thermal Control Products IT Enclosure Systems.
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Transcript of For Telecom enclosures and shelters Application Guide Thermal Control Products IT Enclosure Systems.
IT Enclosure Systems
For Telecom enclosures and shelters
Application Guide
Thermal Control Products
IT Enclosure Systems
About us
We are a supplier of reliable, low-cost, energy-efficient climate control solutions with precise thermal and humidity control for enclosures in telecommunication, IT Industry and automation applications. Huarui Cooling Products are specifically designed for cooling electronic temperature sensitive equipment in challenging environmental conditions.
We can not change the weather, but when it comes to controlling the temperature and relative humidity, under the most extreme conditions, HUARUI thermal control is globally acknowledged as one of the world’s leading experts.
IT Enclosure Systems
Selecting a cooling solution
Heat could affect or damage the electronics inside a cabinet. Some of this heat is dissipated through the cabinet walls. Depending on the size of the cabinet and the ambient temperature, this way of heat removal could be adequate for the application.
Another way of removing heat from a cabinet is by using Fresh Air Cooling. This could be accomplished with a combination of fans and filters. This type of thermal management solution may be used when the installation site is relatively clean and cool such as an office building or inside a cool telecom shelter.
When the electronics inside a cabinet need to be protected from contaminating elements, the recommended solution is to use a Closed-loop cooling system like a heat exchanger, an air conditioner or a thermo electronic cooler (Peltier). This is what is usually used in harsh environments such as outdoor applications in telecom BTS, oil rigs, substations and/or when temperature and humidity levels inside the enclosure are critical.
IT Enclosure Systems
Closed-loop Cooling
In a closed-loop cooling system the cabinet is sealed from the outside and therefore the components are protected from elements of the exterior environment.
There are two separated air cycles:The internal cycle which forces the hot air through a cooling core andthe external cycle which forces the hot air out of the cooler.
IT Enclosure Systems
Cooling technologies
We provide three types of climate control for enclosures
Passive Cooling: Heat Exchanger (HEX)
Active Cooling: Air Conditioners (AC)
Active Cooling: Thermal Electronic Cooler (TEC) Peltier
IT Enclosure Systems
Heat Exchanger
Heat exchangers can be used when the components inside the cabinet can operate at a temperature above outside air temperature.
The temperature inside the cabinet will be slightly above the outside air temperature.
The heat exchanger keeps the air circulating inside the cabinet which does not allow hot spots to form.
IT Enclosure Systems
Air conditioner
Air conditioners should be used when the temperature in the enclosure must be maintained at or below outside air temperature.
Air conditioners will remove humidity from the cabinet.
The AC unit keeps the air circulating inside the cabinet which does not allow hot spots to form.
IT Enclosure Systems
Thermal Electronic Cooler - Peltier
TEC modules are solid-state heat pumps that operate on the Peltier effect, which have no compressor, no refrigerant and require little or no maintenance and have a long life operation.
Provides below outside air temperature cooling.
Fast response with very accurate temperature control.
Small size, light weight and suitable for compact enclosures.
IT Enclosure Systems
Choosing Passive vs. Active cooling
Temperature inside the enclosure Heat Exchanger
Air Conditioner
Peltier
Must be lower or equal to outside temperature - X X
Could be slightly above outside temperature X - -
Humidity inside the cabinet Heat Exchanger
Air Conditioner
Peltier
Must be kept low - X X
IT Enclosure Systems
Installation guidelines
The installation site and the positioning of the cooling unit must be selected in such a way as to ensure good air circulation inside and outside the unit. Make sure that inlet air and outlet air are not obstructed. This is critical to maintain the best cooling efficiency.
Do not position the components inside the cabinet too close to the air conditioner outlet in order to maintain an optimal cooling airflow at all times. Try to arrange the equipment inside the cabinet in order to ensure even air circulation. Do not direct the cool air directly to a warm air stream coming from an active electric device such a rectifier or inverter in order to prevent an air short-circuit condition.
The following examples will help avoid some of the pitfalls that could affect the performance of the thermal management system.
IT Enclosure Systems
Inside the cabinet
Cool air coming from the fan should be able to circulate inside the cabinet and around the components
Poor arrangement inside the cabinet could cause the cool air to be returned to the return inlet (air short-circuit) without cooling the components
Air flow critical area
IT Enclosure Systems
Inside the cabinet
Air flow critical area
Air deflectors could help direct the cool air where is most needed
A deflector in the return inlet helps to avoid air short-circuits
IT Enclosure Systems
Inside the cabinet
A duct directs the outside fresh air to the cooling unit air inlet
Air ducts help direct the exhaust hot air to the outside of the cabinet
Short-circuit is prevented
Inside the cabinet installation
IT Enclosure Systems
Outside the cabinet
This is a good design where hot air being exhausted from the cooling unit does not mix with fresh air intake
Air intake
Air exhaust
Another problem: The louver angle could allow rain water and dust infiltration
This design presents potential problems: Air exhaust from the unit could be mix and be reabsorbed by the air intake.
Louver design
IT Enclosure Systems
Outside the cabinet
Air intake
Air exhaust
This design presents potential problems: Air exhaust is to close to air intake and hot air could be reabsorbed by the cooling unit.
Louver design
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Outside the cabinet
Poor design: Louvers too small for adequate air exhaust
A good louver design will allow maximum air-flow to minimize air drop pressure and reduce noise
Louver design
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Outside the cabinet
When using an additional cowling, care has to be taken to avoid reducing air-flow.
Louver design
Exhaust opening of the heat exchanger
Louver area on cowling should be at least 50% larger than HEX opening
IT Enclosure Systems
Filter or not?
It is not recommended to install an air filter on Huarui heat exchangers. The core material is made of epoxy coated aluminum with fins spaced at 3-4 mm. This corrosion free surface coating prevents accumulation of dust and improves efficiency.
Air filters might be necessary with air conditioners and Peltier units depending on the environmental conditions of the site. (Dust, sand, debris, insects)
Standard units have no filters.
When installing a filter make sure it has easy access for maintenance.
IT Enclosure Systems
Noise emission
Modern environmental requirements demand low noise levels for telecommunication cabinet products, especially when located in offices or urban areas. The spaces available are limited, and the power and electronics packaging density are increasing.
The main noise source of telecommunication cabinets is the cooling fan, and the fan noise interacts with the cabinet structure and cavities in a complicated way. If the fan noise can be decreased, the total noise will also decrease. The use of sound absorbing materials like foam and a labyrinth air path can help reduce the overall noise level.
If your power source is native 48VDC (or -48VDC) as part of a telecom or off-grid solar application, DC air conditioners are your most efficient cooling choice. DC brushless fan motors can greatly reduce energy consumption, and run with super low noise.
IT Enclosure Systems
HuaRui Thermal control Technology
Suzhou Huarui Thermal Control Technology Co.,LtdPlant A2, No.2, Tian'e Dang Road, Wuzhong District,Suzhou, Jiangsu province, 215104CHINATel: +86 512 66570331/66570332Ext: 819 (For overseas sales )Fax: +86 512 68792690e-mail: [email protected] site: www.hauruicooling.com
IT Enclosure Systems8 Chemin Abri Du BoisChelsea, Ottawa-GatineauQuebec – J9B-1S7CANADATel: +1-819-866-3020Fax: +1-819-483-1630e-mail: [email protected] site: www.itenclosuresystems.com
