The 6AG1221-1BH32-2XB0 is a SIPLUS variant of the S7-1200 16-point digital input module. It accepts 24 V DC signals with a signal "1" threshold of 15 V DC at 2.5 mA, making it compatible with standard 24 V PLC sensors and dry contacts. The inputs are arranged in groups of four, sharing a common return per group — plan your field wiring accordingly. Diagnostics are built in: the module reports wire-break and short-circuit alarms to the CPU, and it monitors the load voltage supply. Each input can be configured for status and diagnostics via TIA Portal. Power draw from the backplane bus is 130 mA at 5 V DC; the module itself dissipates 2.5 W typical. The SIPLUS design extends the temperature range to -40 °C to 70 °C. Cold restart is guaranteed down to -25 °C. The module measures 45 mm wide, 100 mm high, 75 mm deep. A front connector is required but not included.
Compared to the standard 6ES7221-1BH32-0XB0
Configuration in TIA Portal is identical. The module's order code is recognized as a SIPLUS device, so the software automatically applies the extended temperature derating curves. No special steps required.