Recently, I visited an overseas company that produced tractor axles. They had a variety of CNC mills. Inside the facility, the ambient temperatures were extremely high, above 45 deg. C. For electronics and electrical equipment, this is the worst type of condition. For every 10 deg. C above the operational temperature limit, the life of an electrical component is cut in half. To reduce premature equipment failures, it is important to keep these components cool.
In this facility, they customer had seven CNC mills machining different axles. Each machine had a control panel that contained VFDs (Variable Frequency Drives) to control the X, Y, and Z axis. The components inside were cooled by a Freon-based A/C unit mounted in the door. But, every year during the hot months of summer, they would have one or two of the A/C compressors overheat and fail. Without the necessary cooling, the VFDs inside the panels would trip from the high temperature alarm and shut down the CNC machine.
Besides the need for constant preventive maintenance, the A/C themselves are very susceptible to high ambient temperatures. The fan that blows the air across the condenser to cool the Freon is now blowing much warmer air. The cooling capacity is affected negatively which means that the A/C compressor has to run longer in hotter conditions. With lack of proper maintenance and a high ambient heat load, A/C panel coolers will fail, shutting down the entire system. Speaking with the Production Manager, he stated that after a failure, it could take up to a week to get a service repairman and the replacement installed. He understood that time is money, and he was losing much money every day that his CNC mill was inoperable. He needed a better way to keep his machines operating, even during the hottest days of summer.
EXAIR has a solution to keep the electronics cool in these type of conditions for these types of applications. It is the EXAIR High Temperature Cabinet Coolers. The High Temperature Cabinet Cooler System is set up to deliver cooling power even under hot applications up to 200° F (93°C). To get the appropriate cooling capacity for his panels, the Production Manager filled out a Cabinet Cooler Sizing Guide. From his information, I calculated and recommended the model HT4340-240. It has a cooling capacity of 2,800 BTU/hr in a very compact, dust-tight NEMA 12 design. This system included a thermostat and a 240Vac solenoid to turn the compressed air off when the set point is reached during cooler temperatures or off-hours. EXAIR can also offer thermostats with solenoid voltage options of 115Vac and 24Vdc for ease of installation. Cabinet Coolers do not require any maintenance or Freon, and they do not have any moving parts to wear; making them very reliable and long lasting. Once the customer received the model HT4340-240, they had it installed in about three hours, not a week. The CNC mill was back in operation and machining parts.
Cabinet Cooler Systems can withstand very demanding applications like the one above. With proper selection and guidance, you can make sure that your equipment will be able to handle the hot days of summer. EXAIR can size a Cabinet Cooler for you by simply filling out the Cabinet Cooler Sizing Guide and sending it to an Application Engineer. We look forward to helping you with your heat related issues.
Summer sun photo by Alexas_Fotos. CC0 Createive Coomons license.