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BASIC COOLING METHODS Forced Ventilation Air Cooling

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BASIC COOLING METHODS Forced Ventilation Air Cooling

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BASIC COOLING METHODS Forced Ventilation Air Cooling

Order Online Request Pricing View Our Clients How to Get a Quotation Contact Us View My Invoice BASIC COOLING METHODS By Kooltronics Forced Ventilation Air Cooling In clean, non-hazardous environments with acceptable ambient temperatures, a simple forced-air cooling system utilizing ambient air is usually adequate. Combined with a low-cost air filter, such devices generally meet the heat removal needs of typical electronic and electrical equipment (Fig. 1). FIGURE 1 Export Information ¡Hablamos Español! Buy Online Airfield Heliport Obstruction -Appoch Lighting Systems -Obstruction Lighting -Solar Obstruction Lights -Power Backup for Airfield -Runway Lights -Solar RunWay Lights Edge -Wind Cones -Solar Powered Wind Cones Automation -Data Acquisition -SCADA Communications -Remote Control
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Components -Batteries -Enclosures -Enclosures Air Conditioners Computers -Computer Solar Chargers Electronics -Timers Fuel Cells Government Hospital -Hospital Signals -Medical Grade UPS -Inverters Ambulance EMS Lighting Fans, Packaged Fans, and Centrifugal Blowers can be used to pressurize or exhaust cabinet air. The ambient air should be filtered before it enters the cabinet.

-Arms
-Bullet Proof LED Fixtures -Explosion Proof Lights -LED Street Lights -Poles -Solar LED Lighting Power -Battery Chargers -DC to DC Converters -Inverters 120 VAC 60Hz. -Inverters 230 VAC 50Hz. -Inverters Accessories Security -Cameras -Cameras Enclosures -Infra Red Ilumintators -Gate Openers -Gate Openers Solar Powered Solar Energy -Charge Controllers -Portable Battery Charger -Solar Modules -Mountng Stuctures Solar Systems IF INTERNAL CABINET TEMPERATURE CAN BE GREATER THAN THE AMBIENT AIR USE A HEAT EXCHANGER Closed-Loop Cooling In harsh environments involving high temperatures, heavy particulates, oil, or chemicals capable of damaging components, ambient air must be kept out of the enclosure. Sealed enclosures are generally used, with closed-loop cooling consisting of two separate circulation systems in a single unit. One system, sealed against the ambient air, cools and recirculates the clean cool air throughout the enclosure. The second system uses ambient air or water to remove and discharge the heat. Packaged Blowers mount to the internal cabinet mounting rails. They are used to pressurize the cabinet and provide filtered ambient air. IF AMBIENT COOLING AIR CAN BE USED AND THE SYSTEM HAS LOW STATIC PRESSURE USE A FAN IF AMBIENT COOLING AIR CAN BE USED AND THE SYSTEM HAS HIGHER STATIC PRESSURE USE A BLOWER

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-Disaster Relief Veicle -Home Solar Power Systems -Portable Solar Generator -Solar Power AC -Solar Power DC -Solar Power UPS Traffic -Accessories -Battery Backup -24/7 Traffic Flashing Beacons -LED Traffic Signals -Portable Traffic Signals -RailWay -Remote Controlled Signals -Solar Powered Traffic Lights -Solar School Zone Flashing Beacons -Traffic Controls -Traffic Lights -Traffic Speed Awareness UPS Backup Systems -UPS Airport Generators -UPS Energency Generators -UPS Hospital Generators -UPS Traffic Generators -UPS Fuel Cell Generators Visual Signals -Explosion Proof Rotating Beacons -Marine Solar Powered Beacons -Rotating Beacons -Solar Powered Beacons Water Pumps -Solar Powered Water Pumps Wind Generators -Wind Generators Accessories -Wind Generators Systems

IF INTERNAL CABINET TEMPERATURE MUST BE EQUAL TO OR LOWER THAN THE AMBIENT AIR USE AN AIR CONDITIONER A comprehensive discussion of Closed-Loop Cooling appears later in this Design Guide. FILTRATION Filtration of contaminated air can be accomplished in some installations to permit forced convection cooling of electronic equipment. Generally, contamination can be broken down into two major categories: airborne particulate matter and corrosives. In most cases, particulate matter can be filtered out and the air made safe for the cooling of heat-producing equipment. However, removal of corrosives by filtration generally requires processes that are too costly and/or too airflow restrictive. Therefore, isolation of the enclosure contents is usually necessary. Careful consideration must be given to the type and severity of the conditions to be encountered. Filters must be able to protect the enclosure at the worst-case level of contamination anticipated. Once the system is installed, adequate preventive maintenance is crucial. Filters must be cleaned or replaced regularly, or means must be provided for continuous monitoring of the filter condition. In order to prevent choking of airflow, it is important for the filter inlet opening to be at least as large as the total area of all air outlets. Inlet and outlet areas should be determined after allowance for impedance of grille materials or other barriers. Air inlets and outlets should be as far apart as possible, so the air is forced to circulate through all heat-producing components. All air inlets should be filtered, whether the air enters through a fan or blower, or directly into the cabinet for exhausting, when pressurization is not feasible. STANDARD FILTERS Filters used with typical electronic equipment cooling devices are usually the viscous-impingement type and are approximately 65% efficient. They utilize fibers that have been coated with a nondrying, tacky substance which traps particulates as air is drawn through. Usually constructed of aluminum foil or flock- coated pleated wire screen, the filters can be cleaned, recoated and re-used indefinitely. Often, filters of this type are used as prefilters in multiple filter systems to extend the service life of high efficiency or absolute filters. HIGH EFFICIENCY FILTERS High efficiency or absolute filters are available in efficiencies ranging up to 99.97% on 0.3 micron size particles. The filter media is a pleated paper which operates as a strainer, since its openings are physically smaller than the particulates it is designed to intercept. This type of filter offers relatively high resistance to airflow and is employed only where more common filter types are incapable of providing acceptable levels of protection. In applications where such filters are required, provision must be made for adequate airflow to overcome the higher resistance in addition to the cooling airflow needed. FLOW MONITORS Where higher levels of contamination exist or can develop rapidly, filtered cooling air packages should be equipped with some form of flow monitor. In the event of a reduction in air delivery below a minimum acceptable level due to a clogged filter, a flow-sensing or temperature-sensing device triggers warning alarms or shuts down affected equipment. Pressure differential switches, which respond to pressure drops across an air filter, are often employed, as are simple vanetype airflow velocity sensors or thermostatic over-temperature detectors located at equipment hot spots. At times, flowand temperature-sensing devices are employed in combination. In this way, relatively low airflows are accepted when the ambient temperature is low. At higher ambient temperatures, reduced airflow, resulting in excessive component temperature, activates the warning device or shuts off power. This arrangement permits maximum filter utilization and safety to the equipment. The need for flow monitoring should be evaluated carefully because of the added cost of the various devices required.

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VARIABLE SPEED BLOWERS Become eDealer Export ¡Hablamos Español! The optimum open-cycle system for use in contaminated environments combines appropriate air filters and cooling-effect detectors with a variable speed blower that adjusts its operating speed to provide the desired cabinet air temperature, as sensed at some point within the enclosure. Since blower air delivery is directly proportional to motor shaft speed, airflow rate can be adjusted to a minimum compatible with a clean air filter and low ambient temperature. Should ambient temperature increase or the filter clog with contaminants, the sensor and controls would demand an increase in motor speed until the new conditions were satisfied. The variable speed blower is self-adaptive to changes in ambient temperature, air density, line voltage, power dissipation in the enclosure, and to the degree of filter-loading. Since the blower operates at the minimum speed and air delivery compatible with cooling, both power consumption and the rate of contaminant accumulation on filter surfaces is greatly reduced, compared to a constant speed blower designed to satisfy worst-case conditions. This increases filter life and reduces filter maintenance to a minimum. Conversely, as the filter loads, blower air delivery could increase to levels beyond those that would be obtained under constant speed conditions. Again, cost must be considered. CORROSIVE ATMOSPHERES Corrosive environments, such as those found in chemical plants and in industries where processes result in harsh chemical by-products, usually preclude the use of filtered ambient air for forced convection cooling. Corrosives generally cannot be filtered out by normal filtration methods, and scrubbing techniques that must be used to rid air of corrosives are complex, costly, and often not satisfactory. For such applications, the cooling method requires isolation of the sensitive components subject to damage from the offending substances. The solution is usually closed-loop cooling - Heat Exchangers or Air Conditioners which consists of two separate circulation systems in a single unit. One recirculates clean cooling air through the electronics within the sealed enclosure, while the other discharges the heat removed from the cabinet to the ambient air or into water for removal. If the corrosive atmosphere is normally within an acceptable temperature range, air-to-air Heat Exchangers can be used to provide cooling for equipment enclosure. When both high ambient temperatures and corrosives are present, either Air Conditioners or water-to-air Heat Exchangers must be employed to cool the hot components. Regardless of the cooling apparatus chosen, it must be constructed of appropriate corrosion-resistant materials, or be treated with corrosive-resistant coatings, to ensure long, trouble-free operation under the conditions to be encountered.
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Care should be taken to review the particular conditions involved. In most cases, a system can be designed to meet specific requirements at moderate cost. CLOSED-LOOP COOLING Many applications using sophisticated electronic/electrical components require a closed-loop cooling system to dissipate heat buildup without introducing outside contaminated air. Closed-loop cooling is required when equipment is operated in hostile environments containing dirt, oil, humidity or corrosives, which adversely affect the performance or ultimate survival of the components. The presence of airborne particulate matter compounds the difficulty of controlling the temperature of the equipment in the enclosure. HEAT EXCHANGERS For installations that can operate at above-ambient temperatures, Heat Exchangers provide moderate-cost closed-loop cooling. Available in both air-toair and water-to-air versions, there are models covering a wide range of cabinet sizes and performance capacities. Depending upon the model selected and the heat load, near-ambient to moderately-above-ambient temperatures can be achieved.

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For applications that can utilize Heat Exchangers, the advantages compared with Air Conditioners include:
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Lower initial cost Lower power consumption Simpler construction Fewer operating components Lighter weight

AIR-TO-AIR HEAT EXCHANGERS Advanced air-to-air Heat Exchanger designs for cooling enclosures include two types of heat transfer methods. One design consists of a finned-tube coil which contains liquid refrigerant. The warm air exhausted from the equipment cabinet to the Heat Exchanger is directed past the coil, causing the refrigerant to boil and absorb heat. The resultant refrigerant vapor rises to the upper portion of the tubes, where the heat is removed by the cooler ambient air and the refrigerant condenses back to liquid, completing the cooling cycle in a continuous process. The most recent developments in enclosure Heat Exchanger design employ highefficiency heat transfer elements fabricated of embossed convoluted metal foil or thin-film polymer material, constructed into two totally separate air paths. The air leaving the hot enclosure is directed through one side of the exchanger, where the heat passes through the element walls into the ambient-side airstream and is dissipated. Figure 3 illustrates heat transfer in air-to-air Heat Exchanger applications.

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WATER-TO-AIR HEAT EXCHANGERS If ambient air cannot be utilized directly as a cooling medium, another costeffective method of cooling is a water-to-air system (Fig.4). Water is used to remove heat from air circulated within the electronic or electrical enclosure.

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Cooling water is circulated through a finned-tube coil, which is installed in a compartment isolated from the enclosure to protect the contents from possible leakage of water. As the heat-laden air circulates through the coil, the heat is absorbed by the water and carried away, in a continuous process. Water-to-air systems are easy to install and usually require minimum maintenance. The water used must be reasonably clean and cold enough to ensure proper operation of the cooling system under the most severe anticipated conditions. In cases where sufficiently cold water is available, below ambient-temperature cooling can be achieved.

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AIR CONDITIONERS Air Conditioners are required where the equipment operating temperature must be kept at or lower than the ambient room temperature, and/or the cabinet must be sealed from oil, dust, fumes and other contaminants. Specially packaged vapor compression Air Conditioners (Fig. 5) protect the components and furnish the required cooling. Such Air Condition-ers employ hermetic refrigeration systems with additional controls. They provide enclosure and air-path geometries for direct installation to the equipment cabinet and accomplish the following:

1. 2. 3. 4. 5.

Isolate the interior of the equipment enclosure from ambient conditions Cool the air within the enclosure to the optimum temperature for the sensitive components Circulate the air within the enclosure to equalize temperature and increase heat transfer from hot components Automatically vary cooling rate to maintain close control of equipment temperature Reduce humidity harmful to sensitive components

Air Conditioners that are used to cool enclosed equipment differ radically from room Air Conditioners. In the area of temperature control, for example, most electronic systems are adversely affected by large line transients typical of Air Conditioner compressor cycling. Electronics also exhibit sensitivity to electromagnetic interference caused by thermostat contacts. The control system of an Air Conditioning package must be designed accordingly.

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In addition, the field experience of many compressor manufacturers has indicated that the frequent start/stop cycling, typical of standard Air Conditioner operation, shortens compressor life. These factors have led to the develop-meant of techniques for close control of internal temperature over a wide range of ambient conditions, without turning the refrigeration compressor on and off and without employing electricallycontrolled solenoid valves. All temperature control for KOOLTRONIC Air Conditioners is accomplished by means of proportioning valves activated by pressure signals within the Air Conditioner hermetic system. Generally, load temperature can be controlled to ±5°F over a range of power dissipation, without the use of thermostats. Frequent start/stop cycling of the compressor is eliminated, thus assuring longer compressor life. Recent developments in temperature requirements for enclosed components has led to the addition of adjustable Low Temperature Control thermostats in all KOOLTRONIC Air Conditioners to prevent over-cooling. EMI/RFI suppressors are included to control the line transients associated with compressor cycling and thermostat operation. Hermetic Air Conditioners are available in air-cooled and water-cooled models. AIR-COOLED AIR CONDITIONERS Heat removed from the enclosure containing hot components is discharged by circulating the ambient air through the condenser coil and returning the heated air to the ambient. There are vertical and horizontal types for exterior mounting to side panels, doors, or the top of the enclosures, and for various internal positions. WATER-COOLED AIR CONDITIONERS Intended primarily for extreme operating conditions of high-ambient temperatures or severe contaminants, these units utilize water as the medium for heat dissipation. The heat is absorbed by cool water circulating through a coaxial condenser coil, following which the heat-laden water is discharged or recalculated after cooling

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VAPOR COMPRESSION CYCLE

Heat is removed by enclosure Air Conditioners and discharged by means of the vapor compressor refrigeration cycle. This takes place in a hermetically sealed system, utilizing either an air-cooled or water- cooled condenser heat exchanger. A schematic ofa typical Air Conditioner is presented in Figure 6. The compressor forces refrigerant, in vapor form, into the condenser heat exchanger, where it is cooled either by ambient air, driven between the fins by a specially engineered blower, or by cool circulating water. As it cools, the refrigerant condenses into liquid, which is passed through a filter to remove impurities and excess moisture. The liquid refrigerant flow is metered by a thermostatic expansion valve or capillary tube, to control its admission to the evaporator. The thermostatic expansion valve is a feedback control device which regulates refrigerant flow on the basis of conditions sensed at the evaporator outlet. The capillary tube is a long, small-diameter tube which employs pressure differential and complex two-phase internal flow dynamics to meter refrigerant to the evaporator. The refrigerant enters the evaporator as a liquid beginning to vaporize. As the blower-driven heated air from the enclosure passes through the evaporator heat exchanger, the refrigerant absorbs the heat and the conversion to vapor is completed. Any moisture present in the air is removed by condensation. This cool, dehumidified air is then returned to the cabinet.
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After the heat absorption phase, the refrigerant passes into an accumulator, where any remaining vaporized liquid is separated. The gas then returns to the compressor, to repeat the cycle in a continuous process. The total heat rejected at the condenser is all of the heat entering the system from the enclosure at the evaporator heat exchanger, heat of compression and heat rejected by the compressor motor, since the compressor is cooled by the refrigerant gas returning from the evaporator. Typical air temperatures during the cooling process are: cooled air to enclosure, 75°F; heated air returning from enclosure, 100°F; ambient air cooling condenser,105°F; air rejected from condenser, 140°F. TEMPERATURE CONTROL Typical refrigeration and Air Conditioning systems control temperature by on/off compressor cyclingas air temperatures fluctuate between minimum and maximum thermostat settings. Compressor start-up often introduces substantial transients into the circuit powering the equipment to be cooled. Thermostat or relay operation results in electromagnetic inter- ference. Both of these factors can adversely affect the function of electronic equipment. On/off compressor control necessitates choosing between large temperature excursions or frequent compressor cycling. Furthermore, frequent start/stop operation exposes internal compressor components to electrical and mechanical strains not encountered during continuous operation. The use of electrical controls to handle high compressor start-currents results in eventual erosion of the control contacts themselves. In order to eliminate the possibility of these problems, KOOLTRONIC Air Conditioners feature a continuously operating compressor and non-electric proportional control system, which result in more stable equipment temperatures and prolonged life for the compressor and the control system. Both blowers and the compressor start simultaneously with the application of power to the unit, and continue to operate until power is removed at the time of equipment shutdown. The control bypass valve, shown in Figure 6, permits refrigerant, in gas phase, to be injected at the inlet to the evaporator heat exchanger. This hightemperature, high-energy gas presents an artificial heat load and permits the effective cooling rate to be varied as necessary to maintain essentially constant temperature of the air returned to the enclosure. (It is normally factory set to deliver air at approximately 70°F.) This control also prevents evaporator freezeupsdur-ing periods of low heat load or low ambient temperature. Although the above control system works effectively at most times, there are instances of over-cooling due to low heat load or low ambient temperature. In order to prevent that condition, Low Temperature Control thermostats and EMI/ RFI suppressors have been added to all KOOLTRONIC Air Conditioners. When activated, the Low Temperature Control shuts off the compressor and condenser (ambient side) blowers. The evaporator (enclosure side) blowers continue to circulate the air through the enclosure and Air Conditioner. When the air temperature again reaches the level at which cooling is needed, the
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compressor and condenser blowers résumé operation. AMBIENT TEMPERATURE RANGE Most KOOLTRONIC Air Conditioners are designed to operate at ambient temperatures ranging from 50°F to131°F. Optional Low Ambient Kits allow operation in ambient temperatures as low as 0°F. Maximum operating ambient temperature decreases linearly with altitude at the rate of 3°F per1,000 feet between 2,500 and 7,500 feet, where maximum operating ambient temperature is 110°F. The ability to operate at high ambient temperatures permits KOOLTRONIC Air Conditioners to be installed in close proximity to furnaces and other heat-producing equipment. For applications in ambienttem-peratures higher than the rated maximum, consultation with the KOOLTRONIC Engineering Depart-ment often provides the solution. CONDENSATION High ambient relative humidity does not affect the rated capacities of KOOLTRONIC Air Conditioners. They're designed for installation on reasonably tight enclosures of relatively limited internal volume. Normally, only sensible heat loads are imposed on the Air Conditioner. Even at an ambient temperature of 95°F and a relative humidity of 100%, the air within a typical electronic equipment enclosure 21/2 feet square and 6 feet high will contain only small amount of water in vapor form. As the temperature of the air being circulated within the enclosure is reduced from 95°F to 70°F, theater will be condensed quickly in the evaporator heat exchanger and be disposed of through the drain in the condensate tray at the bottom of their Conditioner. Unless the enclosure is totally sealed, some slow invasion of ambient air will take place through cracks and seams in the cabinetry and the front panels. However, even at ambient relative humidifies of 100%, the infiltration rate is normally so small that the effect on cooling capacity of latent heat of water vapor condensation in the infiltrating air is negligible. Cooling performance of the Air Conditioner is reduced if its capacity is used for the condensation of excessive moisture. This occurs if the enclosure is poorly sealed oris open for long periods, under high humidity conditions. A continuous flow of condensate denotes that these adverse conditions are present and should be remedied immediately.

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SIZING CLOSED-LOOP COOLING EQUIPMENT In forced convection cooling of enclosures, cooler ambient air is drawn or forced through the components in an enclosure and discharged. When electronic/ electrical enclosures are sealed to keep out moisture, dust, dirt and other contaminants, the heat generated by the components is trapped and closedloop cooling (air conditioner or heat exchanger) is needed to maintain the optimum environment for the components. The heat generated by the components is the INTERNAL HEAT LOAD. Because of the internal heat being generated, there is typically a temperature differential between the inside and the ambient air outside the enclosure. Heat is conducted through the exposed area of the enclosure from the warmer to the cooler space, and is known as the HEAT LOAD TRANSFER. Since Air Conditioners cool to below ambient, the Heat Load Transfer is a heat gain into the enclosure, whereas it is a heat loss out of the enclosure when Air-to-Air Heat Exchangers are used because they do not cool to below the ambient. When sizing an Air Conditioner or Heat Exchanger using the methods on the following pages, if the Internal Heat Load (in Watts or BTU/Hr.) is known, it is the value used in Step One. When it is not known, there are several methods of estimating, including (1) Component Rated Heat Production; (2) Air Flow Heat Rise; (3) Sealed Enclosure Temperature; (4) Incoming-Outgoing Power; and (5) Component Efficiency. Of these, the most accurate and least timeconsuming is Method (3), which is the method we recommend for uninsulated enclosures. The following steps should be followed: (A) The Enclosure must be operating at its highest work load. (B) All openings are sealed and air-moving equipment turned off. (C) Measure the inside air temperature near the top of the Enclosure. (D) Measure the ambient air temperature and determine the differential. (E) Calculate the exposed surface area of the Enclosure (sides and top) in square feet. (F) Refer to the Temperature Differential Heat Gain/Loss Chart, at the temperature differential determined in (D) and multiply the Watts/Square Foot by the exposed area (E). This is the approximate Internal Heat Load in Watts. For BTU/Hr, multiply by 3.413. The Heat Load Transfer calculations required are provided in Steps Two and Three under Heat Exchanger Sizing and Selection or Air Conditioner Sizing and Selection. TEMPERATURE DIFFERENTIAL HEAT GAIN/LOSS CHART FOR UNINSULATED ENCLOSURES

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AIR CONDITIONER SIZING AND SELECTION Air Conditioners for cooling electronic/electrical enclosures should be selected to provide adequate cooling for the anticipated worst-case conditions. For best results, Panel-Mounted Air Conditioners should have the cool air inlet at or below the lowest significant heat-producing component and the return air port should be above the highest such component. The capacity (BTU/Hr) should be approximately equal to the Internal Heat Load plus the Heat Load Transfer (see Sizing Closed-Loop Cooling Equipment), but should not be over-sized, as this will result in excessive cooling which may affect component performance or cause “sweating” of the Enclosure during high humidity conditions. Normally, no additional provision is needed for the humidity in the Enclosure at start-up because it will be dissipated very quickly from a properly-sealed Enclosure. A determination should be made of the appropriate mounting position—side panel, door, internal or top. Although most KOOLTRONIC Air Conditioners are equipped with Condensate Evaporators (or are available as an option) and all have condensate drains, it is preferable to not place an Air Conditioner directly above electronic/ electrical components if the application is likely to be subject to high humidity, which will infiltrate an imperfectly sealed cabinet. The maximum allowable internal cabinet temperature (Ti) should not exceed the heat tolerance specification of the most sensitive component in your system. NOTE: This selection process applies only to indoor gasketed enclosures which are uninsulated. Before proceeding, read Sizing ClosedLoop Cooling Equipment. For applications involving outdoor locations, solar load, non-metallic or insulated enclosures, consult KOOLTRONIC for assistance. The model numbers of KOOLTRONIC Air Conditioners reflect the refrigerant, as of the publication date. A 4 between the A and C signifies R134a; a 3 signifies R22. The Technical Data shown is as determined by testing for UL certification. As more R134a-type compressors become available, R22 units will be redesigned for R134a which may affect performance.

TO DETERMINE REQUIRED AIR CONDITIONER CAPACITY

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AT EXCHANGER SIZING AND SELECTION The proper selection of a Heat Exchanger is determined by how many WATTS can be dissipated at a given temperature differential. Since a Heat Exchanger uses ambient air or available water for cooling, the enclosure cannot be cooled below a temperature slightly above that of the air or water entering the Heat Exchanger. Therefore, the greater the temperature differential, the higher the capacity of the Heat Exchanger. Consequently, the smaller the temperature differential required in an application, the higher the capacity of the Heat Exchanger needed to achieve it. The amount of heat to be dissipated is the Internal Heat Load less the Heat Load Transfer (heat conducted through the uninsulated walls of the enclosure). The performance of Heat Exchangers is expressed in WATTS/°F. In the preferred “Air In” method, the Watts/°F depicts the amount of heat the Heat Exchanger is capable of dissipating per degree Fahrenheit of temperature differential between the entering air or water temperature and the maximum allowable internal enclosure temperature. The calculation process requires (a) the amount of heat to be dissipated, (b) entering air or water temperature, (c) maximum allowable internal enclosure temperature and (d) the dimensions of the enclosure. The maximum allowable internal cabinet temperature (Ti) should not exceed the heat tolerance specification of the most sensitive component in your system. NOTE: This selection process applies only to indoor gasketed enclosures which are uninsulated. Before proceeding, read Sizing Closed-Loop Cooling Equipment. For applications involving outdoor locations, solar load, nonmetallic or insulated enclosures, consult KOOLTRONIC for assistance.

TO DETERMINE REQUIRED HEAT EXCHANGER PERFORMANCE IN WATTS/ °F—Air In Method

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This is the rating (Watts/°F Air In) based on the temperature of the air into the heat exchanger, after exiting the hottest area of the enclosure. Refer to the Heat Exchanger Index and Selection Guide for the unit that most nearly matches the required performance and dimensions.

Another rating, (Watts/°F Air Out) is based on the lower temperature of the cool air as it exits the heat exchanger into the enclosure. This rating may be used if the coolest air can be directed for spot cooling of components in the portion of the enclosure where the air enters from the heat exchanger.

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Outdoor, Pole, Wall, Pad, and Traffic NEMA Enclosures Racking and Non Racking Metal Cabinet Enclosures
The enclosures are normally used to house electrical controls, terminals and instrumentation. Typical industrial applications include traffic control, electronics and telecommunication. The cabinets are available in many sizes and configurations, including double door and four door versions Pre-Configured Outdoor Cabinet Solutions Configured Outdoor Cabinet Solutions are designed to meet the most popular cabinet needs. All cabinets are made from Alum flex material, a unique material, designed to give the best durability at the lightest weight Outdoor Series Cabinets The 777 series cabinet is a new design in communication cabinet enclosures, being as rigid as steel and yet feather light. This series cabinet offers all the protection needed for tokay's outdoor requirements. Features front and rear doors, adjustable rails and a sunshield that sits 1/2" off the enclosure. Ultimate security is provided by a three point locking system. Class 250, NEMA 4 rated. The OkSolar series cabinets offers a powder baked cream color option. Pole or Wall Mounted Cabinets Used in wall or pole mounted applications, the OKPOk series is a totally weatherproof Class 250, NEMA 4X rated enclosure. Each cabinet is a compact design and features a single door with fixed 19" rails. Also includes pre-drilled holes for connector and power cord access. Apron protects rear connections and fan from rain Point to Point Multi-Point Radio Cabinet Aluminum outdoor electronic cabinet with stationary 19" rails, 4 outlet gang box for receptacles, four .65" holes for N -type RF connectors, four 3/4" holes for power knockouts on bottom and two-hole tab electrically bonded to the cabinet chassis. Beige powder coat finish. Front door only. Fan, filter, heating and cooling are optional. Buried Battery Enclosures: Burial Battery enclosure hot dipped galvanized chest style enclosure for four Group 8G8Ds and Polyethylene Enclosures, Legs Removable Environmentally Controlled enclosures and Cabinet weatherproof Aluminum Cabinet Enclosures, Environmentally Controlled Cabinet Outdoor Cabinet for Communications Microwave Radio Equipment and Traffic control products Enclosures Quality, Environmental and Safety Management Manual Thermal Management. ELECTRONIC ENCLOSURE COOLING SYSTEMS RANGING FROM 1,000 TO 20,000 BTUH WITH UL TYPE 12, 4, 4X, AND NOW 3R !
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BASIC COOLING METHODS Forced Ventilation Air Cooling Heat Dissipation Air Conditioners Sizing and Selection Heat Exchanger Sizing and Selection Fan, Blower Sizing and Selection Heater Sizing and Selection Electrical Enclosure Cooling With Special Purpose Air Conditioners

IP66 rating weatherproof type battery box
We offer a 12VDC-24VDC-36VDC-48Volts IQUPS.com power system installed into any OK enclosure optional
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Components > Rack Power Distribution Components > Rack Systems

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BASIC COOLING METHODS Forced Ventilation Air Cooling
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Fuel Cells Generators Backup Solar Power AC UPS Generators > Network Server UPS UPS Generators > Industrial UPS UPS Generators > Data Center Facility UPS UPS Generators > PC Workstation UPS UPS Generators > UPS Emergency Systems

Adjustable 19" or 23" Standard EIA Racking, Front and Rear Doors, 3 Point Locking System, NEMA 4, 4X
Outside Dimensions 39"H x 26 3/4 "D x 25"W Inside Dimensions 35"H x 26 1/4"D x 24"W 2 Sets of 19" Racking w/ Removable 19" Rail Cage WRAP AROUND ALUMASHIELD (POLE OR PAD MOUNTABLE) Item# 777007 Outdoor Rack mount Enclosures

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BASIC COOLING METHODS Forced Ventilation Air Cooling

To Check Prices Click Here > CHECK PRICES > Components > Enclosures Click on Picture for more information

Series Enclosures - Custom Order 4 Sets of Adjustable 19" or 23" Racking, 2 Front and 2 Rear Doors, 3 Point Locking System, NEMA 4, 4X

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BASIC COOLING METHODS Forced Ventilation Air Cooling

Pole, Wall, or Pad Mount Enclosures

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BASIC COOLING METHODS Forced Ventilation Air Cooling

Traffic Enclosures

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BASIC COOLING METHODS Forced Ventilation Air Cooling

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BASIC COOLING METHODS Forced Ventilation Air Cooling

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BASIC COOLING METHODS Forced Ventilation Air Cooling

Battery Box Enclosures

Climate Control Options Racking and Non Racking Cabinet Enclosures

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BASIC COOLING METHODS Forced Ventilation Air Cooling

Air Conditioners
closed-loop enclosure cooling systems to compliment today's highly engineered work stations. 35% more energy efficient 40% more savings in space 45% lighter in weight AIR CONDITIONERS Top and Side Mount Enclosure Air Conditioners. High Ambient, 120V, 230V and 460V models.

Accessory Options Racking and Non Racking Cabinet Enclosures Pole or Wall Mounting Shelf

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BASIC COOLING METHODS Forced Ventilation Air Cooling

Power System
Battery Backup Systems for LED Traffic Signs Increase the public safety and reduced traffic congestion by allowing traffic lights to function even during a power failure. A typical traffic signal intersection experiences eight to ten local power outages annually. With IQUPS battery backup power, some or all the traffic control signals can continue to operate. This seamless switchover to battery power increases public safety and eliminates the need to dispatch police or other service personnel to direct traffic. If all traffic signals were converted to LEDs, the battery backup system would allow full operation of the traffic signals during a power outage, thus alleviating traffic congestion. Important feature is the battery backup system’s ability to maintain the memory of the traffic signal controller. The controller is responsible for sequencing the on and off times of the various signals. With a battery backup system, the controller’s memory can be maintained and return to normal operation once the outage has ended. This feature has eliminated the time spent to reprogram controllers after a power outage Traffic IQUPS It is designed to provide backup power for critical LED traffic light intersections. With 1,000 watts of true sinewave power available, IQFuel Cell and maintenance free Deep cycle batteries. Traffic IQUPS will drive most large LED systems. Its pure sinewave output is cleaner than utility power, making it ideal for all loads. Total distortion is typically less than 1.5%. Manufactured in the USA to the highest standards possible, Traffic IQUPS system is the best choice for critical load protection. power outage knocked out traffic lights, backup generators, emergency generator Depending on the consumers needs, the IQFuelCell automatically charges the battery with up to 100 Ah per day. As independent power supply or in combination with other systems, the IQFuelCell runs self-sufficiently for months. The circuit is fully protected via breakers and fuses on the AC input, connection to the batteries, and DC loads. Outdoor, lockable, aluminum enclosure includes tamper-proof hardware suitable for pole or wall mounting. DC ripple <50mV.

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Data Acquisition and Remote Monitoring of Energy prOkuction and distribution systems: PV Solar Powered, wind and fuel Cells generators. Data Acquisition Service Data acquisition is the process of gathering information in an automated fashion from analog and digital measurement sources such as sensors and devices under test. Data acquisition uses a combination of PCbased measurement hardware and software to provide a flexible, user-defined measurement system.

Airport and Heliport landing back-up Battery Charger: 12Volts, 24 Volts, 36Volts, 48 Volts -120VAC or 230VAC Using state-ofthe-art, switch-mOke technology, the DLS Power Supply series is engineered with the user and variable environmental conditions in mind. Extra care has been given to insure many years of service-free operation, even when subjected to extremely harsh conditions. Batteries are charged quickly and efficiently without over charging and pumps, motors, and fans operate perfectly for prolonged life. IOTA Engineering uses advanced switch mOke technology to bring to market highly sophisticated electronic converter/power supplies at appealing affordability. Exceptionally clean DC output insures pumps, motors, fans, and lights work perfectly. This means longer life for any connected load; virtually no AC ripple to cause static or premature failure of radio or television equipment. Inverter/Charger Available in 12 - 24- and 48-volt mOkels, it provides utility-grade output power and offers high surge capacity 105 VAC/60 Hz - 105 VAC/50 Hz - 120 VAC/60 Hz - 220 VAC/60 Hz - 230 VAC/50 Hz-DC to DC Converters -DC to DC Converters Din Rail -Din Rail Linear Power Supplies -DIN Rail power supplies -Din Rail Single Phase Power Supplies -Din Rail Unregulated Line Power Supplies -Din Rail Voltage Regulator -Inverters Accessories -Inverters DC/AC -Mini Power -Power Supplies -Power Transformers -Transformer

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BASIC COOLING METHODS Forced Ventilation Air Cooling

IQEnergy: IQ Fuel cells are now available as an alternative source for renewable energy. Unlike traditional power generators, they don't require gasoline to generate power. They also provide an alternative to solar generators because they do not depend on any external power gathering equipment. These units are compact, durable, and built to power a wide range of applications. The Best Generator Ever! Applications: Airports, Computer Rooms, Hospitals, Traffic, UPS Smart designs with IQ Fuel Cells for smart energy applications Contact us tOkay! >

We offer a 12V-48Volts IQUPS.com power system installed into any OK enclosure RECTIFIERS 12V: 40A, 60A 24V: 20A, 40A, 60A 48V: 5A, 10A, 20A, 25A, 30A, 40A, 50A IQUPs.com Compact DC Power System is an industry leading DC power system optimized for the demanding power needs of wireless communications and broadband access equipment. Requiring only 2RU (87.6mm) of rack height, the Compact DC Plant is the mOkular, flexible solution for a wide range of applications. Backup Power Systems

Inverters (XDI) 48V, Scalable from 5 amps to 250 amps 12V and 24V, Scalable from 20 amps to 300 amps Flexible AC Input, DC Output, and Battery Interfaces Advanced Digital Control and Communication. Solar Battery Chargers Solar Battery chargers foldable Solar battery Charger extremely rugged and easy to carry and deploy OkSolar military power requirements. The overall benefits of our military solar power products are to, enable extended missions, improve logistics by enabling field charging thereby reducing the number of batteries in the field and provide a significant cost reduction when compared to primary batteries.

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Adobe PDF Files Many OkSolar documents & catalog pages require the latest version of Adobe Acrobat Reader that may be downloaded free at: You can get this application for Free at http://www.oksolar.com/pdf

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BASIC COOLING METHODS Forced Ventilation Air Cooling

OkSolar.com Serving The Industry Since 1988. All rights reserved. All trademarks or product names mentioned herein are the property and responsibility of their respective owners. Credit Pictures provided by PIX along with DOE/NREL Email to Us | Our Philosophy |Terms & Conditions | Powered By GeneralCommunications.com

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