Since the early 1990s, the Fieldbus protocols have become the preferred industrial network system for distributed control. Machines designed around these standardized networks have evolved to become more robust and environmentally resilient to meet demanding applications of ever increasing complexity.
Because of these requirements, the M8 and M12 standard, IEC61076-2-101, was accepted as a method for ensuring a robust, consistent and reliable interconnection between components. While the M12 standard was initially adopted by the automotive industry, it quickly spread into other application areas such as CNC, packaging and food and beverage.
IEC61076-2-101 identifies different types of “coding” to ensure connections within specific applications, though use is not restricted to those applications. The “coding” of the connector is defined in the keying of the interconnection, with contacts numbering between 3 and 12 positions for M12.
- A-coding: general sensor connections, primarily in Europe
- B-coding: primarily sensor connections for Profibus
- C-coding: general sensor connections, primarily in North America
- D-coding: industrial Ethernet
- P-coding: various uses
The earliest M12 connectors were threaded and connector mates screwed on. As more industries embrace the M12 standard, mating connector interlocking has improved with quick-lock designs such as the SPEEDCON style locking mechanism by Phoenix Contact, which allows connector mates to form a tight, locked and sealed connection in 1/8th of a turn. Such connections are generally IP67 (Ingress Protection) rated and are backwards compatible with screw-on threaded connector mates.
Schneider Electric Motion has released a variant of the Lexium MDrive product with three M12 style connectors using the SPEEDCON design in NEMA 23 / 57 mm and NEMA 34 / 85 mm motor sizes. Currently available is the programmable Motion Control (RS-422/485) version with CANopen, Pulse/direction and Ethernet TCP/IP versions available soon.
The connector scheme for the programmable Motion Control version is:
- Power: 4-position B-coded (Male)
- I/O: 12-position A-coded (Male)
- RS-422/485: 5-position A-coded (Female)
The different fieldbus versions of the Lexium MDrive with circular connectors are designed to make cross-connecting impossible.
These are available with compatible mating cordsets and USB to RS-422/485 communications converter.