Enclosures reliably protect electronic components that control process engineering systems, machine tools and production facilities. They accommodate all the necessary energy supply, control and monitoring components. As digitalisation progresses, these components are becoming increasingly intelligent and a growing number of networked devices are being added to help make systems more productive, flexible and energy-efficient, for instance.
At the same time, the number of continuously running high-performance electrical components is also on the increase. These components generate waste heat that can cause enclosures to overheat. The consequences range from premature wear in electronic components to stoppages and even fires.
All this is more than enough reason to take a closer look at the most common causes of enclosure overheating. We also offer some tips on how to prevent overheating despite increasing power densities.
Why do enclosures overheat?
Enclosures overheat for many different reasons. The following overview of the most common causes shows where the biggest risks lie.
Climate-control-related causes of heat generation
| Reason for overheating | Description of problem |
|---|---|
| Insufficient climate control | Having no cooling systems at all or systems in the wrong dimensions results in heat accumulation, which leads to overheating |
| Inadequate maintenance of cooling technology | Failing to check equipment can cause a climate control malfunction, e.g. because of reduced air throughput due to soiled filter mats |
| No transparency regarding actual heat generation | Failing to continuously monitor temperatures means that critical heat-related problems go undetected |
High component density and faulty equipment
| Reason for overheating | Description of problem |
|---|---|
| Excessive component density | When enclosures are packed full of components, air can’t circulate, which makes localised heat accumulation more likely |
| Poor electrical contacts | Loose, corroded or faulty connections increase resistance and, consequently, the generation of heat |
Climate-control-related causes of heat generation
In many cases, enclosures lack efficient climate control. However, this is crucial for reliable operation. It ensures fail-safe production by preventing overheating. Using the right solutions can prevent planning mistakes and operational errors relating to climate control.
Insufficient climate control
To ensure effective cooling, it is vital to know how much waste heat the components installed actually generate. Otherwise, the cooling solution either ends up being too large and results in unnecessary costs, or it isn’t powerful enough and the enclosure still overheats, despite having a cooling system. To avoid such planning errors, Eplan can calculate the total thermal heat loss of the electrical components installed. On this basis, our RiTherm planning tool suggests the appropriate climate control to ensure a needs-based cooling solution is selected when planning the enclosure.
Inadequate maintenance of climate control technology
A suitable cooling solution prevents enclosure overheating. Since climate control units themselves are subject to natural wear and tear, however, it is advisable to use high-quality units that are impressively durable and support predictive maintenance. With the Blue e+ units from Rittal, for example, this process takes place via an IoT interface. As a result, impending malfunctions can be identified in good time and interruptions to operations can be prevented.
Lack of transparency regarding heat generation
How is heat actually generated in an enclosure? It can often be tricky to answer this question while systems are up and running. However, a lack of transparency regarding heat generation in enclosures makes it impossible to identify risks in a timely manner. This is another instance where the IoT interface of the Blue e+ units comes in. The connection between these climate control units and the higher-level energy management systems gives production managers a comprehensive insight into the actual temperatures in their enclosures. That means they can monitor whether the climate control units are indeed cooling components properly and reliably. They can also spot changes that have nothing to do with the actual cooling process.
High component density
Tightly packed components prevent air from circulating and increase the likelihood of heat accumulation in the enclosure. Consequently, the available space in the enclosure should be used in a way that leaves sufficient room for air exchange. When planning an enclosure, the following aspects are important:
- Choosing the right enclosure size and depth
- Finding the optimum arrangement for components inside the enclosure
- Ensuring well-thought-out cable routing that saves on space
This guarantees that air can circulate evenly and prevents any localised heat accumulation. Software solutions from Rittal and Eplan help enclosure manufacturers make sure their enclosure planning does not create thermal risks. The fact that critical components are automatically inserted into the digital model with an exclusion area around them means that they themselves ensure the necessary spacing.
Heat resulting from undetected faulty electrical contacts
Undetected poor or faulty electrical connections are a further factor when it comes to excessive heat generation in enclosures. Loose contacts increase electrical resistance, which leads to additional heat generation. Regular maintenance is vital to prevent faults of this kind. If a defect still occurs between these regular inspections, prompt detection is crucial. Monitoring based on the CMC temperature sensor from Rittal can help with this.
Summary
Enclosure overheating can affect operational reliability and overall equipment efficiency. Consequently, a holistic approach to enclosure cooling is called for – from climate control and appropriate allocation of enclosure space to electromechanics and maintenance. Notwithstanding increased power density, taking these aspects into consideration ensures a control cabinet helps keep systems working properly over a long period while also fulfilling its key protective functions – protecting components from moisture, dirt and electromagnetic interference, and protecting people from risks associated with electric currents.
FAQs
1. Why do enclosures overheat?
Overheating occurs due to the absence or incorrect dimensioning of climate control solutions, high component density, inadequate maintenance and poor electrical contacts. Failure to monitor temperatures can also pose a risk.
2. What are the consequences of enclosure overheating?
It leads to premature wear in electronic components, to production stoppages and, in the worst-case scenario, to fires. This has an adverse effect on operational safety and results in higher costs.
3. How can enclosure overheating be prevented?
By ensuring needs-based climate control, regular maintenance, temperature monitoring and the well-thought-out arrangement of components. Tools such as RiTherm and IoT interfaces help with planning and monitoring.
4. What role does climate control play in enclosure cooling?
A correctly dimensioned climate control solution prevents heat accumulation. RiTherm can calculate the heat loss to ensure an appropriate cooling solution is selected.
5. Why is the maintenance of cooling technology so important?
Soiled filters and defective components reduce cooling performance. Predictive maintenance, e.g. using the IoT interface of the Blue e+ series, detects problems early on and prevents malfunctions.
6. How does component density affect the generation of heat?
Tightly packed components prevent air from circulating and make the localised accumulation of heat more likely. Optimising the enclosure size, cable routing and digital planning, including exclusion areas, prevents thermal risks.
7. What temperature monitoring solutions does Rittal offer?
IoT-compatible climate control units and CMC temperature sensors enable the kind of continuous monitoring that means critical temperature changes can be detected early on and countermeasures can be initiated.
Dr. Dirk Pieler
Executive Vice President Business Unit Industry Solutions at Rittal
With his many years of industry experience, Dirk Pieler is helping to advance the digital transformation and automation in enclosure manufacturing.