Integration notes
The Siemens 6ES7155-6AU00-0DN0 is a PROFINET interface module for the ET 200SP distributed I/O station. It carries a two-port switch with IRT (isochronous real-time) that holds cycle jitter to 0.25 µs, and supports MRP/MRPD media redundancy for ring topologies. The I2t rating of 0.09 A²·s is the figure to use when sizing the input-side circuit protection. Module draws 24 VDC from the bus and dissipates a typical 1.7 W. Firmware shipped at V4.0.
Real-time and redundancy
IRT mode establishes deterministic data exchange with the controller, necessary for high-speed motion or position capture. Jitter of 0.25 µs guarantees repeatability. MRP client capability allows up to 50 devices in the ring; MRPD extends that to 30 devices while supporting planned (yet-elastic) data streams. The integrated switch eliminates the need for an external switch in the station.