The Siemens 6ES7441-2AA05-0AE0 is a SIMATIC S7-400 CP 441-2 coupling module for point-to-point serial connections, with two variable interfaces and a configuration package on CD. It handles ASCII, 3964(R), and RK 512 protocols at rates from 300 bps up to 115.2 kbit/s, and includes a printer driver supporting HP-Deskjet, HP-Laserjet, and IBM-Proprinter models. The module draws up to 300 mA from the 5 V DC backplane bus (without interface module), and also requires a 24 V DC supply. Typical power loss is 2.7 W including a 2×20 mA TTY module.
The 115.2 kbit/s maximum transmission rate across all supported protocols (ASCII, 3964(R), RK 512) sets the ceiling for point-to-point link speed — enough for printer output or moderate-speed device polling, but not for high-throughput data logging. Operating temperature range is 0 °C to 70 °C, with humidity up to 95 % non-condensing. This covers most control-room and light-industrial environments, but not extended outdoor or washdown zones. Memory requirements on the S7-CPU memory card run 1 to 5 KB for parameters, 0 to 55 KB for message texts, and 0 to 64 KB for loadable drivers — plan your CPU memory budget accordingly per interface. Customer-specific drivers are not reloadable, so the module is limited to the built-in protocol set and the listed printer drivers.