electrical enclosure

Are you a wizard? If you watch pro football, you’re probably familiar with Tony Romo. He’s the former Dallas Cowboys quarterback who has seamlessly transitioned into broadcasting. Tony has an uncanny gift for predicting plays before the snap, so much so that people joke that he must be a wizard. Check out this clip https://tinyurl.com/4rr5khbe from the Patriot’s win over the Chiefs in an AFC Championship Game, and prepare to be amazed. 

Much of Tony’s gift comes from his experience under center, coupled with an ambiguous term called “Football I.Q.”

When it comes to designing cabinet enclosures, especially when doing thermodynamic calculations – there’s a bit of wizardry. Some of what is considered best practices are things you learn in university. But the lion’s share of knowledge comes from experience. Like in most industries, electronics design is going through an upheaval in the workforce as veterans of the trade retire, while young engineers enter the workforce to pick up and carry the workload. 

Today we’re going to talk about cabinet thermostat heaters – the “do’s and don’ts” we’ve collected over our years of experience from talking directly with customers around the world. Allow us to impart some of our wizardry:

You may ask yourself – did someone violate the last “DO NOT” instructions and mount their heater near a flammable surface? The answer, believe it or not, is YES. No one was injured, but on a recent field visit, we found a thermostat heater mounted on a wooden 1×4. Yikes! 

While there will still be those that cut corners, touch-safe heaters from STEGO are manufactured with safety in mind. The design of the heater utilizes natural convection, which results in a circulating current of warm air. The surface temperatures on the accessible side surfaces of the housing are minimized because of the heater design. This STEGO heater is suitable for permanent operation. If you follow the operating instructions, you can install a touch-safe heater and know you’ve done all you can to protect anyone working near the cabinet internals.

We’re not wizards, but hopefully, this information helps you keep your design safe from spells and incantations!

Designing complex electronics that perform perfectly outdoors is, well, complex. At STEGO, we believe that protecting those complex projects from extreme climates should be the simplest part of your design. That’s why we use German engineering to create the highest quality thermal management components to protect your designs from anything Mother Nature throws at it. We’ve been pioneering Thermal Management for over 40 years now. With STEGO parts installed, you can rest easy that your complex design is reliably protected for the long haul.

 

When it comes to designing enclosures that contain electronics for maximum longevity, many factors must be considered, including geographic location, temperature, moisture exposure, and the risk of induced condensation. Some designers assume that their NEMA enclosure is waterproof, and so…why worry about all that?

In a recent Stack Exchange web post (https://tinyurl.com/4cmzph46), the author asked for help regarding a sealed electronics enclosure that “had the top cover … screwed on properly, and there was no way water (could) get in.” However, there was clear evidence of condensation after investigation of an intermittent functional failure. 

How did this happen?

There is a misconception that NEMA 4 enclosures provide all the protection needed to prevent moisture-related failures. Even though NEMA 4 is recognized as the standard for keeping moisture from entering an enclosure – it does NOT prevent condensation-induced risks. 

Condensation is caused by warm moist air coming into contact with a surface that is colder than the air’s dew point. Most designers know to account for extreme temperature swings and relative humidity; great designs also account for the condensation-induced use case. 

Induced condensation can stem from two scenarios:

  1. high humidity in combination with day-to-night temperature swings (in some parts of the world, temperatures exceed +50°C. In others, they fall to –40°C), or
  2. heat generated from running electronics in combination with ambient cold temperature (less widely known).

Either scenario above could result in undesired condensation. Over time, the electronics exposed to this scenario could lead to potential device failure, manifested as a short circuit, corrosion, or contamination by mold and other organisms. These could also lead to unexpected water drainage from enclosures and the potential risk of shock to employees.

Beyond the physical issues created, consider the time and resources spent finding a malfunctioning terminal or other electrical components that have been affected by moisture is somewhat difficult as any related problems are not always critical in the first place. As the malfunction triggers inconsistent product performance, the maintenance team must manually check all the electrical components. If there are a hundred electrical boxes to check, the time required to go through all of these can be extensive and result in increased operational costs.

There are different tools to minimize condensation inside enclosures. The most effective tool is a comprehensive design, taking into consideration temperature and condensation. To protect the user and technician, enclosure designs must include devices to compensate for temperature (i.e., thermostat) and condensation (Hygrostat).

Don’t assume that NEMA fixes all that ails you. If you aren’t sure about your design and withstanding pesky condensation, reach out to one of our experts.

Designing complex electronics that perform perfectly outdoors is, well, complex. At STEGO, we believe that protecting those complex projects from extreme climates should be the simplest part of your design. That’s why we use German engineering to create the highest quality thermal management components to protect your designs from anything Mother Nature throws at it. We’ve been pioneering Thermal Management for over 40 years now. With STEGO parts installed, you can rest easy that your complex design is reliably protected for the long haul.

As we get ready for all things Fall & Winter, it’s time to start thinking about things like football, Halloween decorations, and cooler temperatures. Not everyone likes these cooler seasons as much as I do (my wife, for example, would prefer only two seasons: Hot and Hotter), but whether you like it or not, Old Man Winter comes every year.

When it comes to your electronics enclosure, we encourage our clients to think holistically. You need to consider both temperature extremes and condensation risks. Today’s post will focus on cold temperature exposure, but with a wary eye on the risks associated with condensation.

Cold Weather Packages For Your Outdoor Enclosure

 

If you’ve forgotten more than you remember about thermodynamics, that’s ok, because we’re here to help. Beyond simple online heat dissipation calculation tools, there are other questions to consider so that you have a complete solution set for your unique application.

Can one wattage/voltage design work in all geographical locations?

A solution that works only on the test bench but doesn’t consider regional power connections could be problematic. We suggest customized solutions that are specific to your location.

Will AC power always be available?

You may need to consider backup / DC power to maximize uptime. 

Have you considered Touch-Safe / maintenance crew safety?

“Even minimal-voltage installers can still be subjected to alarming jolts, especially if they are working in a hazardous environment such as when they are ungrounded or standing on a wet spot…” says the NECA Executive Director of Standards and Safety.

Does my design need two heaters?

Sometimes one heater is not enough to keep electronics safe in frigid temperatures.

The answers to these questions will determine how best to design a solution that can likely handle anything Mother Nature throws your way. Depending on how you answer these queries will help us guide you down the right hardware path, a path that might lead to a solution involving a:

Our goal at STEGO is to make sure your design avoids potential blind spots. We offer a comprehensive review that takes into consideration both temperature and condensation. We want to minimize the risk of failure, allowing for maximized uptime. Contact us today for a consultation, so you know you’ve selected the right thermal management solution, despite temperature and condensation exposure.

Designing complex electronics that perform perfectly outdoors is, well, complex. At STEGO, we believe that protecting those complex projects from extreme climates should be the simplest part of your design. That’s why we use German engineering to create the highest quality thermal management components to protect your designs from anything Mother Nature throws at it. We’ve been pioneering Thermal Management for over 40 years now. With STEGO parts installed, you can rest easy that your complex design is reliably protected for the long haul.