SIMATIC NET LEAN COMMUNICATION PROCESSOR 6GK7343-1CX10-0XE0 6GK7 343-1CX10-0XE0 6GK7343-1CX1O-OXEO

6GK7343-1CX10-0XE0 | SIMATIC NET CP 343-1 Lean — Industrial Ethernet / PROFINET IO / TCP/IP + UDP + RFC1006 / 2-Port ERTEC 200 Switch / 2×RJ45 10/100 Mbit/s

CP 343-1 Lean — S7-300 Industrial Ethernet in One Module

The CP 343-1 Lean is a single-slot S7-300 communications processor that adds Industrial Ethernet connectivity to SIMATIC S7-300 stations — including TCP/IP-based application protocols, PROFINET IO device operation, and the S7 communication services that SCADA, HMI, and supervisory systems use to read and write PLC data.

The "Lean" designation reflects a deliberate design choice: maximum Ethernet and PROFINET capability at a reduced cost point, without the additional features of the full CP 343-1 Advanced (which adds ISO-on-TCP layer 3 routing, for example). For the majority of S7-300 applications that need Ethernet connectivity — HMI access, SCADA integration, PROFINET IO device operation, or data exchange with other Ethernet-capable controllers — the Lean variant delivers what is needed.

The integrated 2-port ERTEC 200 switch is the feature that most directly affects field installation. Both RJ45 ports connect to the Industrial Ethernet network simultaneously. Instead of requiring an external network switch to create a ring or linear topology through this S7-300 station, the CP 343-1 Lean daisy-chains to the next device in the line directly. One cable enters, one exits — the station is in the ring without any additional hardware.

Key Specifications

Protocol Coverage — What Each Service Handles

TCP/IP and UDP: Standard IP transport protocols. Enable open-standard communication with non-SIMATIC devices — PC-based SCADA servers, data logging systems, ERP/MES interfaces, and third-party controllers that use socket communication.

SEND/RECEIVE with RFC1006: RFC1006 is the standard that maps ISO-layer SIMATIC communication over TCP/IP. S7-300 SEND/RECEIVE connections with RFC1006 enable peer-to-peer data exchange with other SIMATIC controllers or with PC applications using the S7 communication stack (for example, STEP 7 or WinCC).

SEND/RECEIVE without RFC1006: Raw TCP socket communication for devices that require a pure TCP data stream without the RFC1006 ISO-on-TCP encapsulation.

Fetch/Write: Allows a remote device (typically a PC or SCADA) to read or write S7-300 data areas — inputs, outputs, flags, data blocks — without needing the S7 controller's involvement. The CP 343-1 Lean handles the Fetch/Write request and accesses the PLC data itself.

S7 communication (server): The S7-300 responds to S7 read/write requests from S7 clients — STEP 7 online functions, WinCC, TIA Portal diagnostics. The CP 343-1 Lean handles these requests without consuming CPU processing bandwidth.

PROFINET IO Device: The CP 343-1 Lean participates in PROFINET IO as an IO Device (slave). A PROFINET IO Controller (such as another S7-300 or S7-400 with a PROFINET-capable CPU or CP) cyclically exchanges I/O data with the CP 343-1 Lean. This allows the S7-300 rack to be used as a PROFINET slave station in a larger system.

FAQ

Q1: What is the difference between CP 343-1 Lean and CP 343-1 Advanced?

The CP 343-1 Lean handles the communication services listed above — TCP/IP, UDP, RFC1006, Fetch/Write, S7 server, and PROFINET IO device — which covers the majority of S7-300 Ethernet integration requirements. The CP 343-1 Advanced adds ISO-on-TCP layer 3 routing, more simultaneous connections, and additional features for more complex network architectures. For standard SCADA, HMI, and PROFINET IO connectivity, the Lean variant is adequate and more cost-effective.

Q2: Can the CP 343-1 Lean act as a PROFINET IO Controller (master), or only as an IO Device?

The CP 343-1 Lean supports PROFINET IO Device (slave) operation only — it responds to a PROFINET IO Controller but does not itself control PROFINET IO Devices. For PROFINET IO Controller (master) operation on an S7-300, a CPU with an integrated PROFINET port (such as the CPU 315-2 PN/DP) or a CP 343-1 Advanced is required.

Q3: How many simultaneous TCP connections does the CP 343-1 Lean support?

The CP 343-1 Lean supports a defined number of simultaneous configured connections — verify the exact connection count from the CP 343-1 Lean device manual for the specific firmware version installed. The connection types (ISO-on-TCP, TCP, UDP, S7) each consume from the total connection budget. For high-density connection requirements, the CP 343-1 Advanced provides a larger connection capacity.

Q4: Does the CP 343-1 Lean require a separate Ethernet power supply?

No. The CP 343-1 Lean draws its operating power from the S7-300 backplane bus (5V supply from the power supply module in the rack) and from the 24V external supply connected to its power terminal. No separate power wiring to the RJ45 ports is required — the module is powered entirely through the S7-300 rack interfaces.

Q5: What programming software configures the CP 343-1 Lean?

STEP 7 V5.x (Classic) or TIA Portal (with the appropriate hardware support package) configure the CP 343-1 Lean's Ethernet addresses, connections, and PROFINET IO device parameters. After initial configuration download, the module replacement without PG feature allows subsequent configuration recovery over LAN using stored parameters in the S7-300 CPU.