PROFINET Cable

PROFINET Cable Set-up and Definition

The PROFINET cable set up includes multiple components which have different individual assignments. The coat provides protection against environmental influences such as chemicals, heat and mechanical stress such as shock, bending, tear, rubbing and repetitive movement. Underneath is the shield of a flexible metal mesh which supports the electro magnetic compatibility (EMC) of environmental influences. Additionally, the inner shield includes a film which shields the cables from each other. The electric insulation is provided through the shield of each core. Signal, data and power is transmitted through the core of the cable.

The PROFINET cable set-up is standardized in IEC 61784-5-3. Three cable types are available for PROFINET cables with copper cores: Type A, Type B and Type C. They equal the stress through movement of the cable. PROFINET cables are available 2 paired (2x2) and 4 paired (4x2). For 2 pair PROFINET cables the cable diameter AWG22 is up to 19 cores. For 4 pair PROFINET cables AWG23 and AWG24 the standard is defined to up to 19 cores.

PROFINET Cable Installation

Installation and wiring of the PROFINET bus system is outlined in the "PROFINET Installation Guideline". The document can be found on the website of the user organization PNO. PROFINET cables can be installed in star, line, tree or circle structure. PROFINET cables with a high rate for flexibility cycles, processing speed and acceleration are required for mobile applications like a camera on a robotic arm with direct Ethernet connection. The PROFINET cable set-up therefore has to ensure high flexibility and reliability. PROFINET cable are sold per meter. Usually they are ready-made with RJ45 or M12 connectors.

PROFINET Organization

PROFINET(R) is part of the Industrial Ethernet systems. PROFINET(R) users have united in the PROFIBUS PROFINET(R) user organization (German: PROFIBUS Nutzerorganisation e.V., short: PNO). The PROFIBUS user organization releases guidelines for the PROFINET cable set-up and the installation of PROFINET cables.

PROFINET Structure

With the help of the PROFINET standard, components of the decentralized periphery can be connected to the control unit via a single line. According to this concept, parts of the control electronics are moved close to the connected actuators and sensors. The wiring therefore is substantially less complicated and cheaper since single cores from actuators and sensors to the CPU are not needed anymore. Just one single line goes from the periphery to the central automation unit. Therefore, a PROFINET line has to comply to higher standards both in its set-up and in the execution of the installation.

Cables and plugs within PROFINET have to be shielded. The connectors on each end of the PROFINET cable are similar and wired with the same pin assignment. Therefore sockets are required on the side of devices. The length of a PROFINET segment may be up to 100 m.