High temperatures are all too often the prime cause of malfunction and failure in enclosure-housed equipment. And even when devices do not actually fail, their service life is curtailed.
If, for example, variable speed drives operate over time at 15°C above optimum, their life times will be three times shorter. You should, therefore, comply with safety distances and not install drives too close together. And make sure the cabinet is roomy enough and or the cooling system adequate. Otherwise temperatures will rise to well above 70°C.
What effect does seasonal heat have?
When control panel components overheat, so do costs. Not only in business terms, either. In critical continuous processes like traffic control systems the consequences can be costly in human terms, too.
The summer increases the likelihood of overheating and, by the same token, system failure or breakdown.
Whether you are a design engineer, a panel builder, a contractor, or an OEM, you need to be sure that electrical installations do not overheat in summer.
Passive solutions – those designed into enclosures – help prevent overheating. But when they don’t you need to know what active solutions to take.
What is the most economic solution for dissipating heat?
Leveraging the natural properties of air. One such way is to install air outlets at hot spots (e.g. next to variable speed drives) to force ventilation or convection.
Thermostats are an effective thermal control solution. Place them in the hottest part of an enclosure or next to the most sensitive device – which they use as benchmarks.
Use thermostats in conjunction with ventilators for really effective control your enclosure’s cooling system. They dissipate heat economically, ensure an even temperature inside your enclosure, and can secure you energy savings of over 50%.
One proviso, however: the ambient dust content must be low.
What if temperatures rise too high to ventilate?
You should use cooling (or air-conditioning) units. They control the temperature inside the enclosure. Even when outside temperatures are as high as 55°C, they cool equipment efficiently and prevent hot spots from forming.
What about heat dissipation in polluted environments?
An energy-efficient solution in corrosive operating environments is the air-to-air heat exchanger. It draws cool air from separate internal and external air circuits and keeps dust outside your cabinet.
You should use air-to-air exchangers when the temperature outside is lower than inside. They are ideal for equipment rooms and sites that already have air-conditioning.
What about with no external air circuit?
Air-water exchangers are an ideal solution when refrigerated water is available. They are sealed devices that extract large volumes of heat in harsh, highly polluted environments like those in cement or paint works.
How do you know which solution to use?
High-performance software is available on the market today.
All you have to do is enter the thermal parameters and it will calculate thermal balance and heat loss, then suggest the right thermal management solution.
Ever had trouble keeping your enclosures cool? Why not share with us? Or just want to know more?
9 years ago
My name is wahyu, Engineering and Planning manager at Water Utility at Batam, we got the problem with overheat at VSD Control panel, we need your advise about the cooling system that need to be installed at that room.
9 years ago
If you have an overheating inside your control pane, it is indeed necessary to install a cooling solution. To define the best solution for your problem, you can use the software ProClima
Fast and simple to use, you can download it at:
Don (Maintenance Management)
9 years ago
I might add, always have a panel temperature sensor wired into electrical control system to let maintenance know of issue if it arises.
5 years ago
Dear Sir , I have over heating problem in vfd drives which reached nearby 90F in drive temperature while running in full load. Pls give a better solution to make cool my vfd panels