The manufacturing landscape across the world is continuing its rapid evolution. In the UK alone, across such areas of specialism as the Midlands’ automotive hub and Scotland’s emerging space sector, the density of industrial electronics is reaching unprecedented levels.
This means that as of the late 2020s, the drive to fit ever-more power into small cabinets is far from the only challenge in settings like these. Yes, that’s right; we’re referring to the need to ensure the resultant heat doesn’t compromise reliability, safety, and legal compliance.
Why Is Heat a Major Factor in Industrial Electronics?
Whenever current flows through an electronic component, it is inevitable that heat will be generated. This is especially the case for such devices as power semiconductors, resistors, inductors, and transformers.
Over recent years, power densities in industrial applications have increased. This trend has coincided with enclosures becoming ever-more compact to meet space constraints and IP66/67 ingress protection requirements.
Such a combination of factors helps explain why excessive heat can be a significant concern in industrial electronics. If elevated levels of heat in such environments are left unmanaged, this can lead to issues including:
· Reduced component longevity. Many devices are subject to what is sometimes called “the Arrhenius rule”. This is the popular “rule of thumb” where every rise of about 10°C above a temperature of roughly 40°C to 50°C is believed to approximately halve a given component’s lifespan.
· Derating of performance. Excessive heat often forces semiconductors to be run below their nominal current rating, so that safe junction temperatures can be maintained (these are typically around 125°C to 175°C maximum, depending on the device).
· In extreme cases, thermal runaway. This refers to a self-accelerating, uncontrollable chain reaction in lithium-ion batteries and other systems, where excessive heat escalates. This can lead to a breakdown that releases toxic, flammable gases.
On top of these risks, regulations and best practices underscore the need for proper thermal design. To refer again to the UK, the IET Wiring Regulations (also known as BS 7671) address surface temperatures in the interest of preventing fire hazards.
Key Heat Transfer Mechanisms
There are three main methods by which heat moves:
· Conduction, which is the direct transfer of heat through solid materials
· Convection, whereby air or liquid movement (whether natural or forced) carries heat away
· Radiation, which is a minor contributor at typical industrial temperatures, but relevant for very hot surfaces.
Effective thermal management optimises all three of these heat transfer mechanisms. All the while, it focuses on minimising thermal resistance (°C/W) along the entire path from the hottest point (normally the semiconductor junction) to ambient air.
4 Common Thermal Management Techniques Across Industrial Applications
The term “thermal management” can be defined as the engineering discipline of controlling heat generation, transfer, and rejection, with a view to keeping critical components within safe operating temperatures.
It is rare for industrial electronics to use the exotic liquid immersion or microfluidic cooling seen in data centres or high-end AI servers.
Instead, there is a tendency to turn to practical and maintainable solutions, such as:
1. Passive Cooling with Heatsinks and Natural Convection
Aluminium extruded or cast heatsinks are very much “workhorses”. In cabinet installations, designers orient heatsinks for vertical airflow, while making sure at least 20mm to 50mm of clearance is provided around them.
2. Forced Air Cooling
This typically takes the form of axial or centrifugal fans mounted on heatsinks or cabinet doors. In parts of the world like the UK, filter fans are an extremely common sight. These devices play an integral role in maintaining positive pressure and keeping dust out, at the same time as providing airflow.
3. Thermal Interface Materials (TIMs)
Often, it is the interface between component and heatsink that represents the highest-resistance part of the path. Options for addressing this can encompass thermal pastes/greases, phase-change materials, and gap pads/fillers for uneven surfaces or larger tolerances.
4. Enclosure Climate Control
For sealed cabinets in harsh environments across such specialised sectors as food and pharmaceuticals, engineers may opt for solutions like filter fans, or air-to-air or air-to-water heat exchangers. Compressor-based enclosure air conditioners have also gained popularity due to their precise control and energy-efficient operation.
Effective Thermal Management Can’t Be Treated as an ‘Optional Extra’
In the sphere of industrial electronics, well-executed thermal management is of critical importance for achieving the uptime, safety, and energy efficiency that manufacturers demand.
We are living in an era of tighter margins, higher power densities, and intensifying regulatory focus on reliability and sustainability.
This backdrop further underscores how investing time in high standards of thermal design can pay dividends through fewer breakdowns, longer equipment life, and reduced whole-life costs.
