Electrical connector considerations in military applications

~ Key design considerations for electrical connector solutions used in the harsh environments often found in the military sector ~ 

In the world of electrical connectors, there is an abundance of options to choose from, which can make identifying the right choice a difficult task. This is made more difficult in mission-critical industries with specific operational challenges, such as the military sector. Here Sean Fitall, senior product manager at military electrical connector specialist PEI-Genesis, discusses the key considerations for a new generation of electrical connectors that deliver reliable performance in military applications.

Electrical connectors used in military applications, such as manned ground vehicles and unmanned autonomous guided vehicles, must often tolerate extreme and harsh conditions. Typically, these include extreme temperatures both hot and cold, rapid temperature and humidity changes, persistent impact and vibration and signal interference.

Furthermore, it is common for military connectors to be in services for two to three decades, amplifying any potential damage or loss of performance over time. This means that connectors intended for use in military applications must be designed with performance and reliability in mind to ensure operational success.

Therefore, to rise to the challenge, military connectors must come equipped with key features such as high durability, easy mating and unmating, a high number of mating cycles to ensure long lifespans, superior shielding performance and high levels of ingress protection.

D38999 connectors

Traditionally, D38999 connectors have been the first choice for use in military applications. First developed in the 1970s and now on its fourth generation design, this is a military-specific connector designed to ensure reliable performance.

D38999 connectors are made up of a hard outer shell, a polychloroprene rubber insert with cavities to house the contacts and a backshell is required on the outer housing of every plug to provide additional shielding and durability. D38999 connectors can be supplied in aluminium, stainless steel, marine bronze or composite materials and then plated in either olive drab cadmium, green zinc cobalt, nickel or black zinc nickel, depending on customer requirements.

Composite options are more popular because they are lightweight and offer high performance levels in harsh environments. They are also all REACH and RoHS compliant (apart from the Olive Drab plating) and all QPL qualified for use in military applications.

Now, electrical connector manufacturers have built on the features that have made the D38999 so reliable in military applications for decades with the introduction of next-generation Rhino 38999 connectors.

Rhino 38999 connectors

Rhino 38999 military off-the-shelf (MOTS) connectors combine the benefits of field proven MIL-DTL-38999 series III circular connectors with low resistance RADSOK® power contacts. This makes them ideal for high power and high voltage applications in harsh environments.

These connectors encompass many key features required in the military sector, such as shock and vibration in accordance with DEF-STAN 00-35 Iss 4 Ch2 01, a Black Zinc Nickel plating that is compliant with restriction of hazardous substances (RoHS) requirements and provides over 500 hours of salt spray endurance and IP68 mated and unmated.

Rhino 38999 MOTS connectors feature a hyperbolic contact design that results in low contact resistance and high contact endurance, while delivering a high current carrying capacity of up to 1,000 A. Furthermore, Rhino 38999 connectors offer IP2X finger protection in accordance with BS EN 60529 mechanical finger and deliver 360˚ screening facilitated with straight or 90˚ EMC backshell.

The superior EMC performance of Rhino 38999 connectors compared to traditional connector solutions enables equipment to meet the requirements of military EMC specifications such as DEF STAN 59-411 and MIL-STD-461.

All of these features combine to offer reliable performance in the most challenging environments and ensure operational success, which are the key requirements of the military sector.

PEI-Genesis supplies Amphenol Rhino connectors and can support customers in the military sector who need guidance on connector specification for a given application. To find out more about PEI-Genesis’ Mil-Spec and rugged military connectors, visit www.peigenesis.com/en/military/military-connectors.html or contact its UK team on +44 (0) 23 8062 1260.