The Siemens SIMATIC RF240R (6GT2821-4AC40) is a compact HF RFID reader with an RS232 interface operating in ASCII/scan mode. Measuring 50 x 50 x 30 mm and weighing approximately 60 g, it connects directly to a PC, operator panel, or serial terminal for simple scan-based identification. The integrated antenna delivers up to 65 mm read range, and the IP67-rated housing ensures reliable operation in harsh industrial environments. The RS232 interface makes the RF240R suitable for standalone identification stations where direct serial connection is preferred over network integration.

How Does the RS232 ASCII/Scan Mode Operate?

In ASCII/scan mode, the RF240R continuously scans for transponders within its read field and outputs detected transponder data as ASCII text over the RS232 serial interface. This mode suits straightforward identification workflows — for example, a quality inspection station where an operator presents a tagged component and the reader transmits the ID to a local PC for verification. The reader connects via an M12 connector to the serial port and is powered by 24 V DC (20.4-28.8 V) with 50 mA typical current draw.

What RFID Standards and Transponders Are Supported?

The RF240R operates at 13.56 MHz using ISO 15693 and ISO 18000-3 standards and is compatible with the full range of Siemens SIMATIC RF200 transponders (MDS D100 through D528 series). Maximum RF data transfer rate is 26.5 kbit/s, with approximately 2.4 ms read access time per byte. The reader processes one transponder at a time. A 3-color LED indicates power/ready (green), transponder present (yellow), and error states (red flashing).

What Are the Installation and Environmental Specifications?

The RF240R measures 50 x 50 x 30 mm and weighs approximately 60 g, housed in PA 6.6 polyamide (anthracite). It mounts using two M5 screws (max. 1.5 N·m torque) directly on metal surfaces with no minimum clearance. IP67 protection provides complete dust-tight operation and resistance to temporary water immersion. Operating temperature range is -20 °C to +70 °C, with storage/transport tolerance of -25 °C to +80 °C. Shock resistance is 500 m/s² and vibration resistance is 200 m/s². MTBF is approximately 430 years.

Frequently Asked Questions

How does the RS232 variant differ from the IO-Link variant of the RF240R?

The RS232 variant (6GT2821-4AC40) uses ASCII/scan mode for direct point-to-point serial connection to a PC or terminal, suitable for standalone identification stations. The IO-Link variant (6GT2821-4BC32) connects to an IO-Link master for integration into PROFINET/PROFIBUS automation networks with TIA Portal engineering. Choose RS232 for simple local terminal applications; choose IO-Link for networked automation integration.

How does the RF240R compare to the RF250R RS232?

Both are 50 x 50 x 30 mm with RS232 interface. The RF240R includes an integrated antenna with 65 mm range, making it a self-contained unit. The RF250R requires a separate external antenna, offering flexible antenna placement at the cost of managing two components. Choose the RF240R for simpler single-unit installations; choose the RF250R when the antenna must be positioned separately from the reader.