Whether hybrid in the short term or fully electric in the future, there will not only be a transition in how these vehicles’ drivetrains are powered, but also all their ancillary equipment currently powered by pneumatic or hydraulic systems, and all these functional elements will need high power interconnects. To date, in military applications with a critical need for ruggedness and reliability as well as high performance, the traditional option has been 38999 screw thread connectors.
As popular as they are, they are not without challenges. They require a two-stage movement to fully mate or unmate - a bit like the screwing action for a standard light bulb: a straight push and a 400° rotation of a threaded lock. Easy enough in most civilian situations but imagine having to do that in a tight space whilst wearing cumbersome protective gear.
What’s more, the full mating of 38999 connectors is only confirmed when the locking ring covers a red band around the receptacle shell at the end of the rotation. It isn’t easy to see in difficult-to-access areas or in high-concentration connector spacing, and this lack of clarity risks to jeopardise the user’s safety or to cause the connection failure.
Singular safety innovation
Smiths Interconnect’s single-pole HBB connector delivered a breakthrough of raw power and ruggedness combined with a simpler, safer locking system. It is based on our patented Hypertac® hyperboloid ‘basket of wires’ contact design which provides contact 360° around the pin and uniformly down its whole length. This has proven to provide a continuous high current no matter how harsh or violent the operating conditions are. The design also gives the pins a smooth and self-wiping insertion/extraction path which reduces resistance to about half that of conventional contacts. This significantly contains the thermal rise that can affect connector integrity, enabling our HBB interconnects to handle high performance even in small assemblies, and also helps give them an unrivalled number of mating cycles.
The HBB’s ruggedised metallic shell is polarised which facilitates initial mating orientation. It also has a quick latch/release mechanism which is more akin to a bayonet light bulb: latching is achieved simply by pushing the plug until there is a ‘click’ and red dots on the plug and receptacle are aligned – which together offers audio, tactile and visual locking confirmation - whilst release requires only a 20° twist-and-pull. Importantly in the field, this allows simple maintenance and quick changeovers of equipment. Unmated, the connector is finger-proof to IPx2 standards and, mated, sealed to IPx7 and IP6K9K, with 360° EMI/RFI shielding also available. Beyond superior performance, this provides important user safety and confidence.
The single-pole HBB connector comes in two versions: size 17 (300 amps) and size 21 (500 amps), both offering a minimised panel footprint and the option of a low profile 90° back shell. And, without the need to leave space for a full gloved-hand grip or visual locking confirmation, designers can group the connectors far closer together than other alternatives allow.
Flexible five
These significant advantages have now been extended with Smiths Interconnect’s new, game-changing five-pole HBB connector, which adds flexibility, redundancy and additional safety to the series’ established high current handling and reliability credentials. Again, benefiting from the super-performing, super-reliable Hypertac® design, the five-pole connector has the same size 21 shell as the 500-amp single-pole, but housing five x size-8 contacts – each of which can handle 60 amps for a total connector rating of 300 amps. Having multiple power channels in a single connector gives engineers greater design flexibility, with the ability to service more systems, or provide back-up lines where redundancy is critical.
The five-pole model also introduces an additional safety feature: a ‘last mate first break’ system, comprising two interlock pins that can be used to automatically shut off power when connectors are unmated. Along with our unique latching mechanism, this makes the five-pole HBB connector an extremely safe, secure, and easy to use and maintain solution, and, as with the single-pole, this further allows designers to group connectors far closer than the next best alternative on the market.
With all these advantages, the five-pole HBB connector has wide application potential in the defence sector, from electric fighting vehicles and Unmanned Aerial Vehicles (UAVs) to missile launcher platforms and ground radar installations. And, with the new safety and easy-use features, we’re seeing increased interest from early industrial adopters as varied as rail transport designers, power plant operators and crane contractors. There’s no doubt that the future for Smiths Interconnect HBB connectors is set to be electrifying!
The new five-pole is an expansion on the existing HBB platform. The five pole configuration consists of the existing size 21 shell but contains five poles, each with size eight contacts as well as two interlock pins. This means that in a very tight space, the customer can run five power lines which increases the connectors’ flexibility and offers the ability to run redundant lines as required.