PROFINET Communication

PROFINET is designed to support all applications in a plant versatilely with one bus.

Therefore, PROFINET has three different performance levels as described below.

For this option, "2 RT (Real-time)" communication is supported.

1. NRT (Non Real-time)

   This communication is based on TCP/IP.

   This is used for applications where real-time communication is not required, such as inter-unit communication and parameter communication.

2. RT (Real-time)

   By adding a software protocol to the standard Ethernet hardware, this method actualizes real-time communication with approximately 10 ms intervals.

   In particular, by defining a priority in VLAN tag (IEEE803.1Q) in Ethernet frame, RT frame is processed with a higher priority to non-real-time data (NRT, TCP/IP, etc.) RT can offer almost the same performance as the existing fieldbus.

3. IRT (Isochronous Real-time)

   Isochronous real-time communication (IRT) guarantees that communication is surely executed within an arbitral communication time (Deterministic) at a higher level than Real-time communication (RT).

   This enables a clock rate of < 1 ms and a jitter precision of < 1 μs.

   IRT is used for applications where a strict real-time performance is required, such as motion control. As a communication hardware, switch-function-embedded special ASIC is used. This method guarantees the real-time performance by dividing the communication band on Ethernet.