Siemens 6ES7241-1AH32-0XB0 SIMATIC S7-1200 CM 1241 RS232 Communication Module

The Siemens 6ES7241-1AH32-0XB0 is a SIMATIC S7-1200 CM 1241 communication module with one RS 232C (V.24) port for point-to-point serial links up to 10 m. It runs the integrated Freeport, ASCII, and Modbus RTU master/device protocol drivers, draws 200 mA max from the backplane 5 V DC bus, and dissipates 1.1 W typical.

Technical Specifications

Certifications & Standards

• CE mark
• CSA approval
• UL approval
• cULus
• FM approval
• RCM
• KC approval
• Marine approval

Selection Notes

Pick the CM 1241 RS232 over the RS485 variant when the connected device -- a modem, barcode scanner, or legacy instrument -- only speaks single-ended RS 232C, since the two interfaces are not interchangeable at the connector or the electrical level. Its 10 m maximum cable length keeps it to point-to-point runs; multidrop or longer-distance links need the RS485 CM 1241 instead. Because Modbus RTU master and device modes are both built into the firmware, the same module can poll a third-party RS232 device as master in one project and answer as a Modbus slave in another without swapping hardware.

Applications

Connecting an S7-1200 CPU to RS232 barcode scanners, weigh indicators, printers, or legacy PLCs and instruments over a Freeport or Modbus RTU serial link.