What this reader does on the line
The Siemens 6GT2821-0AC12 is a 13.56 MHz RFID reader from the SIMATIC RF200 family, built for reading ISO 15693 and ISO 18000-3 transponders. It operates on 24 VDC (21.6–26.4 V range) and draws 0.4 A typical, 0.5 A max. The read range reaches 650 mm, adjustable via transmission power, and depends on the transponder type. Multitag-capable, it reads a byte in 0.6 ms typical. The enclosure is IP65-rated, aluminum with a silver/anthracite finish, sized 200 x 140 x 80 mm (W x D x H). It mounts via 4 M4 screws, 35 mm DIN rail, or an S7-300 mounting rail. The M12, 8-pin connector handles power and communications (RS 422 up to 1000 m, RS 232 up to 30 m). A single external antenna connects via TNC; antenna cable length must be between 3.3 m and 25 m. One digital input and one digital output are available on a separate M12, 4-pin connector. Four LEDs indicate operating status. Shock resistance is EN 60721-3-7 Class 7M2 (300 m/s²), vibration 20 m/s².
The MTBF is listed at 18 years, which reflects a solid reliability figure for an industrial RFID reader in a fixed-mount application. The IP65 rating and aluminum housing make it suitable for washdown or dusty environments. The reader is not IECEx certified, so it is not rated for explosive atmospheres.
The M12 power/communications connector uses an 8-pin female connector; the digital I/O uses a separate 4-pin M12. Antenna cable runs are limited to 25 m maximum and 3.3 m minimum, so plan the antenna placement within that range. The reader supports one external antenna only. The supply voltage is 24 VDC nominal; the reader draws 0.5 A max, so a standard 24 VDC power supply with at least 0.5 A per reader is adequate. The RS 422 interface supports cable runs up to 1000 m, useful for remote antenna placement. The RS 232 interface is limited to 30 m.