What this CP brings to an S7-400 rack
The 6GK7443-1EX10-0XE0 is a SIMATIC NET CP 443-1 communications processor that connects an S7-400 to Industrial Ethernet via ISO and TCP/IP. It supports S7 communication, fetch/write, send/receive with and without RFC, at 10/100 Mbit/s through a single RJ45 port (AUI alternative available). NTP is enabled, so the CP can serve as a time synchronization client for the automation system. The module occupies one single-width slot on the S7-400 rack, with dimensions 25 mm × 210 mm × 290 mm (W×D×H). Power is drawn from the backplane at 5 V DC; no external supply needed. The package is rated IP20 and operates from 0 °C to 60 °C ambient.
NTP and protocol capabilities
NTP is available on this CP, which means the module can synchronize the S7-400 system clock over the network — useful for timestamped alarms or coordinated control across multiple stations. LLDP is not supported, so automated topology discovery (e.g. via PROFINET or network management tools) will not work on this interface. Similarly, SNMP v1 is absent, and there is no web-based diagnostics or MIB support. This is a lean CP oriented toward deterministic S7 communication rather than managed-switch-style telemetry. The required configuration tool is NCM S7 for Industrial Ethernet, which ships with STEP 7 V5.x.
Lifecycle and cross-reference reality
A buyer who sees 6AG1243-2AA30-7XB0 listed as an alternate should know it is an entirely different platform — an S7-1200 AS-Interface master module. It cannot drop into an S7-400 rack, nor does it perform the same Ethernet CP function. No direct second-source exists for this S7-400 slot; stick with the original order code.