What the 6ES7297-0AX30-0XA0 actually is
The 6ES7297-0AX30-0XA0 is the SIMATIC S7-1200 Battery Board BB 1297 — a plug-in module that fits the signal board receptacle of any S7-12XX CPU running firmware V3.0 or higher. Its job is long-term buffering of the real-time clock (RTC), so the CPU retains time-of-day and date stamps across power cycles without a mains-backed supply. It uses a CR1025 lithium cell (not included in the delivery) and signals when that cell needs replacing via a dedicated MAINT LED on the PLC — no up-tower guesswork, just a visual cue that the backup is running low.
Temperature range and environmental tolerance
The IP20 rating means it belongs inside a clean, enclosed panel — standard for S7-1200 signal boards — and the atmospheric pressure tolerance (795 to 1,080 hPa during operation) covers installations up to about 2,000 m altitude without issue. CE, CSA, FM, and marine approvals are all on record, so the board is accepted in industrial, hazardous-location, and shipboard environments across the major regulatory jurisdictions.
The BB 1297 measures 38 mm wide, 62 mm high, and 21 mm deep — a compact footprint that matches the standard S7-1200 signal board envelope. It snaps directly into the SB slot on the CPU face, adding no additional DIN-rail width.
No official successor or cross-reference exists because the part is current. For a line-down replacement, confirm the target CPU firmware is V3.0 or higher — that is the only compatibility gate.