AS-Interface Master for S7-1200 Racks
The Siemens 3RK7243-2AA30-0XB0 is an AS-Interface master module in the S7-1200 form factor. It snaps onto a standard 35 mm DIN rail and draws its supply from the backplane bus at up to 250 mA, with a power loss of 2.9 W. Galvanic isolation is rated at 500 V insulation voltage.
Mounting & Environmental Fit
Enclosure is IP20 and sized 30 mm wide × 75 mm deep × 100 mm high — a narrow footprint that leaves room on the DIN rail. Storage and transport range is -40 to +70 °C; operating ambient is covered in the spec table but typical for a panel environment. Fastens by snap-on onto 35 mm DIN rail, so no tools needed for install or swap.
Protocol Limitations
No SNMP, TCP/IP, PROFINET, PROFIBUS, PROFIsafe, or wireless on this module. Data travels over the S7-1200 backplane bus only, with digital I/O accessed via the process image and analog I/O via data record transfer. If your cell requires a fieldbus gateway, you'll need to add a separate communication processor.