Keeping outdoor control cabinets locked up tight

Several industries commonly place cabinets full of control, communication, and monitoring electronics outdoors. Telecom companies, electric utilities, as well as municipalities that need to safely manage traffic on highways, bridges, and rail systems rely on outdoor cabinets. Additionally, wind and solar farms are now becoming major users of outdoor control cabinets.

On wind farms, electronic controllers and safety subsystems monitor the turbine, generator, tower and environment to keep the turbine operating safely and within prescribed limits. On solar farms, electronics help solar-tracking towers follow the sun.

In all these applications, outdoor electronics enclosures can be hard to reach, rarely visited by maintenance technicians and exposed to harsh weather conditions year round. The hardware must withstand high winds, storms of all kinds, heat, solar radiation, and other severe conditions that can damage electronics if they are not fully protected.

Consequently, it’s critical to specify enclosure latches and hardware that will withstand the weather, without complicating the jobs of the technicians who do visit to fix problems or upgrade equipment. Engineers should consider five factors when specifying access hardware for outdoor control cabinets: durability, ability to withstand vibration, corrosion resistance, ease of use, and ease of installation.
Long-lasting latches

Select latches that will hold access doors firmly closed and last as long as the enclosure. One option is compression latches that consistently compress gaskets surrounding enclosure openings. Compression varies from latch to latch, but one important aspect to consider is the clamping range of the latch. For instance, Dirak Inc., Sterling, Va., carries compression latches with clamping ranges as short as 3 mm to as long as 20 mm.

Fixed-compression latches have fixed cams, so they consistently compress and decompress gaskets to a specific depth. Or designers can choose latches with adjustable compression. These latches allow a user to change the initial and, consequently, the final position of the locking cam. This allows a single compression latch to be used in a variety of applications or to adjust compression on a cabinet over time.

Compressing the gasket along its entire length is important because without consistent force, gaps in the housing perimeter can let in water, dirt, or insects; any of which can damage the sensitive electronics within the enclosure.