Siemens 6ES7540-1AB00-0AA0 SIMATIC S7-1500 CM PtP RS422/485 BA 19.2kbit/s PLC Communication Module

The Siemens 6ES7540-1AB00-0AA0 is a SIMATIC S7-1500 point-to-point communication module, type CM PtP RS422/485 BA, providing an RS422/RS485 serial interface on a 15-pin D-sub socket. It transmits at up to 19.2 kbit/s over cable runs up to 1 200 m and supports Freeport, 3964(R), and USS protocols for connecting third-party serial devices.

Technical Specifications

Selection Notes

USS protocol support lets this module poll Siemens drives (such as MICROMASTER or SINAMICS units with USS interfaces) directly over RS485 without a PROFIBUS or PROFINET gateway, which is the main reason to pick a CM PtP module over a fieldbus communication module for small serial-drive networks. Freeport mode gives the user program full control of the telegram format for connecting non-Siemens serial instruments (scales, barcode readers, third-party controllers), while 3964(R) provides a fixed handshake protocol for point-to-point links to other SIMATIC controllers. At 19.2 kbit/s and 1 200 m maximum cable length, throughput is adequate for polling or parameter read/write but not for high-speed data acquisition.

Applications

Serial point-to-point links to third-party instrumentation, barcode scanners, or older SIMATIC S7-300/S7-400/S7-1500 stations, and USS-based polling of Siemens drives without a fieldbus network.