AS9120B, ISO 9001:2015, and FAA AC 0056B ACCREDITED

What are Circular Connectors and their types?

When you are working with multiple electronic systems, you will likely need a connector part to route power and signals across various applications. Across a myriad of industries, including those operating with aircraft, industrial machines, communications, and more, electrical connectors are needed to join printed circuit boards (PCBs) and modules as a last step during assembly, as this allows for separate circuits to be tested on their own, saving manufacturing time and costs. Many connector types also work as the interface between sensitive electronic equipment and the outside world. With many applications for electrical connectors, different variations are available to accommodate particular connections. As a popular choice for harsh environments, this blog will specifically take a closer look at metric circular connectors, their benefits, and their applications.

All connectors share a number of the same basic elements, with an outer shell protecting the internal elements and two mating ends for joining the circuits. The outer shell, or housing, of the connector is used to protect the many pins and sockets that carry the electricity through the connector. These pins or sockets are also encased in an internal insulator that prevents them from contacting one another. A contact type is manufactured into some aspect of the connector design, determining how the connector will mate with the connecting parts. Whether crimped, soldered, or plugged in, the connector must mate with the other electrical part types in some manner.

Metric circular connectors are unique from other types in their cylindrical design comprising pins for electrical conductivity. They connect to applications through the mating system of screw threads and offer a robust waterproof cable-to-panel/PC board interface for demanding end-use applications. Furthermore, circular connectors are more compact than their rectangular counterparts, and they operate at as low as -40 degrees, working well for applications in low temperature environments. The number of pins in a circular connector varies by type and by size, so metric circular connectors are named as such, with the letter M followed by a number to indicate the size of the connector.

For example, an M12 metric circular connector is the largest design and can contain up to 12 pins, while an M5 is smaller and contains no more than 4 connectors. Popular in industrial and automation controls, the M12 offers strong and reliable connections. At the same time, smaller models like the M8 and the M5 work well as compact versions of the M12 with slightly less capabilities. M8 metric circular connectors are used in applications where a robust metal shell is required for durability, including medical devices, ruggedized data loggers & sensors, electronic gauges & metering, and avionics & marine electronics. Meanwhile, M5 designs are often used in applications involving transportation & control systems, automated doors & ramps, sensor connectivity, and many data & communication devices.

Regardless of their size category, all metric circular connectors form compact and rugged applications due to their IP67/68 protection and -40 °C to +85 °C temperature range. When determining if your application is considered a rugged environment, there are a few factors to ponder. In addition to extreme temperature ranges, rugged conditions include exposure to pressure, shock, vibration, corrosion, rough handling, and risk of explosion. As the mating aspect of circular connectors makes their seal stronger than most and less likely to break, they have a reputation for protecting against many of these factors. When you are in the market for any electrical connectors or other related part types, look no further than Fastener Orbit.

Owned and operated by ASAP Semiconductor, we are a leading distributor of new, used, obsolete, and hard-to-find part types from trusted manufacturers around the globe. With quality at the cornerstone of our operations, we ensure all items in our ever-expanding inventory are vetted for fit and function before shipping all orders to you, alongside their applicable manufacturer trace documentation. Make Fastener Orbit your procurement partner today when you submit a Request for Quote (RFQ) form for any item with all details relevant to your purchase. Using information like target prices, shipping deadlines, and desired quantities, our market experts can best tailor a custom quote for your comparisons within 15 minutes or less. To learn more, contact us at any time via phone or email!


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