Frigid-X™ Cabinet Panel Coolers NEMA 12 For Electronic Control Panels
NEMA 4 Panel Coolers are sepcially designed NEMA 4 enviroments and provide a low cost method of both purging and cooling electrical and electronic control panels by using a stainless steel vortex tube to create cold air from ordinary compressed air. NEMA 4 Panel Coolers series are compact and can be installed in minutes through a standard electrical knockout. There are virtually no moving parts. NEMA 4 Panel Coolers series are for NEMA 4 rated panels.
All Stainless Steel Body and vortex tube, Quiet - Under 70dBA
Contact Nex Flow for assistance in sizing Panel Coolers.
*Cooling effect based on 95 degrees temperature inside cabinet, 100 PSIG (6.9 BAR) compressor inlet pressure, and ºC) inlet temperature. All On-Off control units include the cooling unit, filter with auto drain, cold air distribution kit, solenoid valve and thermostat.
Panel Coolers come with a 5 micron filter with an automatic drain for the compressed air supply to insure clean, dry air and an air distribution kit to circulate the cold air inside the enclosure for even cooling Panel Coolers are available with or without thermostat control. When constant cooling and a constant positive purge is required we recommend the continuous operating version without the thermostat and solenoid valve. The cooling effect can be controlled by adding a regulator in line to reduce pressure for reduced cooling when it is not required and to conserve energy. Systems utilizing a thermostat and solenoid valve saves air by activating the air conditioner only when the internal temperature reaches a critical level. The adjustable thermostat is factory set at °F but can be readjusted on site. Thermostat and solenoid valve systems are recommended where the heat load can fluctuate (such as for frequency drives) and where a continual purge is not required. The thermostat and solenoid "package" can also be added at a later date to a continuous system.
Total heat load consists of the heat transfer from outside your panel and from the heat dissipated inside the control unit. Useful terms, and conversions: 1 BTU/hr = 0.293 watts Typical fan capacity: 4" fan: 100 CFM (2832 LPM) BTU/hr. cooling effect from fan 1.08 x (temp. inside panel in ºF - temp. outside panel in degrees F) x CFM Watts cooling effect from fan: 0.16 x (temp. inside panel in ºC - temp. outside panel in degrees C) x LPM
1. Determine the heat generated inside the enclosure. Approximations may be necessary. For example, if you know the power generated inside the unit, assume 10% of the energy is dissipated as heat. 2. For heat transfer from the outside, calculate the area exposed to the atmosphere except for the top of the control panel. 3. Choose the internal temperature you wish to have, and choose the temperature difference between it an the maximum external temperature expected. 4. From the conversion table that follows, determine the BTU/hr. per square foot (or watts per square meter) for the temperature difference. 5. Multiply the panel surface area times the BTU/hr. per square foot (or watts per square meter) to get the external heat transfer in BTU/hr or in watts. 6. Sum the internal and external heat loads calculated. 7. If you do not know the power used in the enclosure but you can measure temperatures, then measure the temperature difference between the outside at current temperature, and the present internal cabinet temperature. 8. Note size and number of any external fans. Provide this information to Nex FlowT to assist in sizing the appropriate cooling system.
The control panel has two frequency drives totaling 10 horsepower and one module rated at 100 watts. The maximum outside temperature expected is ºC. The area of the control panel exposed sides, except for the top is 42 square feet or 3.9 square meters. We want the internal temperature to be ºC. Total internal power is 10 hp x 746 watts/hp - 7460 plus 100 watts = 7560 watts. Or Total internal power is 10 hp x 2544 BTU/hp = 25440 BTU/hr plus 100 watts x 3.415 BTU/hr/watt = 25782 BTU/hr. Assume 10% forms heat = an internal heat load of 2578 BTU/hr. External heat load: The temperature difference between the desired temperature and the outside is ºC. Using the conversions (and interpolating where necessary) we multiply the area by the conversion factor: 42 sq. ft x 3.3 - 139 BTU/hr or 3.9 sq. m x 10.3 = 40 watts Total Heat Load: 756 + 40 - 796 watts or 2578 + 139 - 2717 BTU/hr. You would use a Model 61040 for constant operation or a Model 63040 for one-off control. (Rated at 2900 BTU/hr or 849 watts).
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Panel Coolers - NEMA 4 - Advantages: 