How to Specify COTS Mixed-Layout Connectors for Military Vehicles
Learn more about the latest lightweight COTS options for mixed-layout connectors from Erich Reichenbach of Reichenbach International.
Connectors for the military should be small, lightweight, rugged, reliable, and versatile as they are exposed to various demanding applications and environments. Here are some suggestions for specifying military COTS connectors.
Size, Weight, and Shape
By conserving fuel, a system can operate longer or go farther. Thus, to lower weight, and thereby save fuel, it is very important to use tiny lightweight metal circular connectors, about 0.3 ounces in weight with a 0.45″ diameter.
To perform various functions such as sending/receiving signals or turning on and off various devices, we recommend two machined (highly reliable) contacts that will carry 3A each and two fiber optic contacts that can send/receive data for a number of computers. Look for these connectors in IP67 water-resistant or non-water-resistant versions, either gold-plated or black anodized-plated. Being circular, they can fit in a small area. (If only 2x fiber optic contacts are required, then a .32″-diameter and 0.1-ounce metal circular connector that meets all the mentioned specifications should be used. If only four contacts are required, such as 2x3A and 2x twisted pair (coax), then an IP67, brass-shelled, 200°C, .32″-diameter, 0.1-ounce metal circular connector can be used.)
Material, Shielding, and IP67
A lightweight, small, brass-shelled connector is ideal since it is rugged, weighs about three ounces, and resists salt water and various chemicals. As a metal, the brass shell also offers EMI/RFI shielding for its 2x3A electrical contacts, and the two fiber optic (polymer fiber optic) contacts can be field-terminated since they do not require any polishing. They also can can be quickly and easily terminated on a PCB via a clamp POF connector containing a diode that converts fiber optic to electrical or vise-versa.
Via its PEEK insert, the connector is rated at -40°C to + 200°C for the electrical contacts, which can be terminated to a rugged Teflon-jacketed cable. Alternately, a highly flexible HFS (flame-retardant and zero-halogen) 2A, 30AWG, black-jacketed cable rated at -40°C to + 100°C can be used for the electrical. For the fiber optic connector/cable, the temperature is about 70ºC.
Plus, via two internal Viton O-rings, the connector’s front and back are both IP67 water-resistant in the IP67 version. These features make it a very versatile connector.
Cost and Weight
The combined connectors and cables weigh far less than electrical connectors and cables; send and/or receive more data than electrical connectors and cables; and are far less expensive than military QPL fiber optic connectors and cable assemblies.
These specifications have required several connectors in the past but today they are available in a single, small connector.
Author Erich Reichenbach is the founder of Reichenbach International Inc.