Siemens 6ES7541-1AB00-0AB0 SIMATIC S7-1500 CM PtP RS422/485 HF 115.2 kbit/s Communication Module

The Siemens 6ES7541-1AB00-0AB0 is a SIMATIC S7-1500 CM PtP RS422/485 HF point-to-point communication module for RS422 and RS485 serial links up to 115.2 kbit/s over a 15-pin D-sub socket, supporting Freeport, 3964(R), USS, and Modbus RTU master/slave protocols. It draws 43 mA from the backplane bus and mounts directly on the S7-1500 rail alongside the CPU.

Technical Specifications

Selection Notes

The HF designation supports 115.2 kbit/s over RS422 or RS485, well above the throughput of the base-level PtP modules in the same product line, and the 4-wire full-duplex RS422 wiring together with RS485 multidrop lets one module reach up to 1 200 m of cable. Modbus RTU master mode addresses up to 32 devices, 1 to 247 with extended addressing to 65535, so this module fits multidrop RS485 networks of Modbus field instruments where a single RS232 point-to-point link would not scale. The 8 kbyte telegram buffer holds more queued 3964(R) or Freeport frames during bursts than a smaller-buffer module handles.

Applications

Multidrop RS485 sensor and actuator networks, Modbus RTU polling of drives or metering devices, and long-distance RS422 links between control cabinets up to 1 200 m, all addressed through the S7-1500 backplane without a separate gateway.