Do you really need a High Reliability Connector?

By David Pike on behalf of Mouser Electronics.

Choosing connectors for demanding applications is now more important than ever. Sophisticated devices are being deployed into harsh environments as industrial users adopt the latest technologies. Designers need to provide connectivity in the toughest conditions, and many are turning to high reliability solutions.

High reliability is the gold standard of the connector industry. It is a term that is often used to describe products with a military pedigree. For decades, manufacturers have offered connectors that conform to military specifications. Subjected to rigorous testing, connectors with a MIL-DTL or BS part number deliver superior reliability in the toughest environments.

This superior performance does come at a price, however, and an expensive MIL-Spec or BS part number is not the only way to obtain reliability. In an era of extended lead-times, rising costs and logistical challenges, perhaps now is the time to stop focussing on high reliability and instead start talking about appropriate reliability.

Mating Cycles
When choosing a connector for demanding roles, most manufacturers publish a minimum mating cycle count in their specifications, as it provides a good indication of how long a connector will last. A military specification connector – the archetypal high reliability solution – might boast a published performance of 500 or even 1000 mating cycles. However, the humble USB connector that has been with us for nearly 3 decades is designed to provide up to 5000 mating cycles, and there are even versions available that will provide a service life of 20,000 mating cycles or more.

Almost all manufacturers who make products conforming to a MIL standard also make the same connector under their own part number. These are usually made on the same production line, using the same materials, and deliver the same performance. As an example, the ever-popular D38999 Series III circular connector is available from Amphenol as the TV, from Souriau as the 8D and from ITT Cannon as the KJA families.

The same is true for D-Sub connectors sold as M24308 and micro-D connectors as M83513. Finding out what manufacturers call their equivalent product can save a great deal of money.

An Alternative Choice
Mating cycles are not the only measure of a connector’s reliability. The environment in which the connector will be used must also be considered. We talk regularly of IP ratings, shock and vibration, and resistance to electromagnetic interference (EMI). The need to perform even under these conditions will have an enormous effect on the design of any connector. There are plenty of connectors that will provide excellent service.

This is important to remember, because connectors do not have to be designed for military specifications to be capable of military-grade performance. Manufacturers like LEMO have been making connectors for decades, subjecting them to a range of tests which prove their suitability in a wide range of industries.

Designed for use in applications where failure is not an option, high reliability connectors provide superior performance in tough conditions. However, the next time you need to choose a new product, ask whether the gold standard is the best solution, or even if a high-reliability connector is needed at all. The connector industry is huge and diverse, and the right solution not need have a high price tag to deliver high performance.