What this part is
The Siemens 6ES7155-6AU30-0CN0 is a SIMATIC ET 200SP PROFINET interface module — the head-end that ties an ET 200SP station (or, via a send BU/BA, an ET 200AL island of up to 16 additional modules) onto a PROFINET network. It carries three Ethernet ports through two BusAdapter slots rather than fixed RJ-45 sockets, so the physical media (copper, fiber, mixed) is a slot decision, not a chassis decision. It runs on a 24 V DC supply and dissipates roughly 4.9 W under typical load, which is the figure to budget on the system power rail when the head-end sits next to a stack of I/O modules.
Timing and redundancy — what the spec actually buys you
IRT is supported across a 250 µs to 4 ms send clock, stepped in 125 µs increments — that range is what determines whether the application fits isochronous motion or stays in standard RT. Maximum jitter is held to 1 µs and equidistance plus H-Sync forwarding are both enabled, so the module is positioned for drives or high-speed I/O where the deterministic gap between cycles matters as much as the cycle itself. PROFINET MRP media redundancy is on the table; MRPD is not — if the design relies on MRPD for parallel-redundant ring reconfiguration, this head-end will not carry it.
Diagnostics, security, and shared-device posture
Status is reported through three front-panel LEDs — green RUN, red ERROR, yellow MAINT — which mirrors the standard Siemens PROFINET diagnostics vocabulary the maintenance tech will already read. Alarms, SNMP, LLDP, and TCP/IP are all on; Modbus TCP is not. Shared-device mode is supported, so two controllers can split the downstream I/O across one head-end when the architecture calls for it. Security is documented against Security Level 1 Test Cases V1.1.1, and I&M0 through I&M3 are populated for asset identification in the engineering tool. PROFIenergy is supported and the module ships at firmware V4.2 — pin that version in the project before commissioning so the controller-side GSD matches the head-end in the cabinet.
Mechanical and environmental envelope
The module occupies 100 mm of DIN-rail width, stands 117 mm tall, and sits 74 mm into the cabinet — no BusAdapter fitted, the unit is approximately 220 g. Autonegotiation and autocrossing are handled by the BusAdapter, so the physical Ethernet segment does not need a manual switch setting; tool-changer docking is supported on both the docking station and docking unit for robotics-side applications. Strain relief is an optional accessory rather than a fixed feature — order it as a separate line if the cabinet sees vibration or if the cable routing puts lateral load on the BusAdapter.
Sourcing posture
Lifecycle is recorded as current in the spec ledger, so the part is being maintained in the active catalog and quoted to order against an RFQ through the usual channel — no last-time-buy window applies.