When hot weather causes the electronics inside a control panel to fail, there is a panic to get the machinery up and running again. The operator might choose to simply open the panel door and aim a fan at the circuit boards. In reality, the fan ends up blowing a lot of hot, humid, dirty air at the electronics where the cooling effect is minimal. If the machinery starts functioning again, the likelihood of repeated failure is great since the environment is still hot and threatens permanent damage to the electronic components and circuit boards. Worse yet, that the open panel door is an OSHA violation that presents hazard to personnel.
A sensible solution
Exair has a complete line of low cost panel coolers that can solve these problems. They mount in minutes through an ordinary electrical knockout and have no moving parts to wear out. Thermostat control which minimises compressed air use is available for all models. All the panel coolers are UL listed to US and Canadian safety standards. Constructed of stainless steel they are robust and assure long life and maintenance free operation.
Exair manufactures special NEMA 4, 4X and 12 Panel Coolers suited to specific requirements. The High Temperature Panel Coolers which are used for ambient of 52 to 93°C are available. Internal components can withstand high temperatures like those near furnaces and ovens etc.
The non-hazardous purge panel cooler systems are suitable for dirty areas where contaminants might normally pass through small holes or conduits. Under normal conditions, the NHP Panel Cooler Systems provide a slightly positive pressure in the enclosure by passing 28 litres of air per minute through the cooler. When the thermostat detects high temperature, it energises the solenoid valve to pass full line pressure to the panel cooler, giving it full cooling capacity.
In panels where the heat load is extremely high, panel coolers of up to 820 W (2800 BTU/hr) are suitable. Stainless Steel NEMA 4X Panel Coolers are suitable for the food service, pharmaceutical, harsh and corrosive environments, and other applications where 316SS is required or preferred. Capabilities of these are 190 to 820 W (650 to 2800 BTU/hr).
Environmental considerations
NEMA 12 (IP52) Panel Coolers (dust-tight, oil-tight) are suitable for general industrial environments where no liquids or corrosives are present.
NEMA 4 (IP56) Panel Coolers (dust-tight, oil-tight, splash-resistant, indoor/outdoor service) incorporate a low-pressure relief valve for both vortex tube and panel air exhaust. This valve closes and seals when the cooler is not operating, to maintain the integrity of a NEMA 4 enclosure.
NEMA 4X (IP56) Panel Coolers offer the same protection as NEMA 4 but are constructed of stainless steel for food service or corrosive environments.
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