Features:
- Provides 24V DC input expansion for S7-200 systems; typical input current 4 mA per channel.
- Only 2 W typical power loss; powered via expansion bus, no external supply needed.
- The module is designed for DIN rail mounting, snapping directly onto standard 35 mm DIN rail.
The 6ES7221-1BF22-0XA8 provides 8 additional 24V DC digital input points for a SIMATIC S7-200 system. These inputs are used to connect field devices such as pushbuttons, limit switches, proximity sensors, and photoelectric sensors that output a 24V DC signal. The typical input current when the signal is “1” is 4 mA – low enough to be driven by most PLC outputs or sensor transistors without overloading. The inputs are not isolated, meaning they share a common reference (typically the 24V DC return). This is typical for basic S7-200 I/O modules and is acceptable for most applications where all sensors share the same power supply.
The 6ES7221-1BF22-0XA8 has a typical power loss of only 2 W, making it one of the most energy‑efficient expansion modules in the S7-200 lineup. This low power consumption is critical because S7-200 CPUs have a limited power budget for expansion modules. For example, a CPU 224 can provide up to 660 mA of 5V power to expansion modules, while each module draws a portion of that budget. The 6ES7221-1BF22-0XA8 draws a small fraction, allowing users to add several modules before reaching the CPU’s limit. The module receives all its power from the expansion bus, requiring no external 24V DC supply connection.
When planning cabinet layout, allow for at least 50‑60 mm of clearance in front of the module. The compact size is particularly valuable in retrofits, where existing cabinets may have limited free space. For engineers designing new panels, the 6ES7221-1BF22-0XA8 allows high I/O density in a small area. Despite its small size, the module includes all necessary status indicators (though not detailed in this document, typical S7-200 modules have LEDs per channel).
The 6ES7221-1BF22-0XA8 Siemens Digital Input Module may still be available for purchase and support from Apter Power beyond
End-Of-Life (EOL)by the manufacturer (OEM).
Siemens 6ES7221-1BF22-0XA8 Digital Input Module Manuals, Datasheets,Drivers,Link
Important Notice:Other accessories,manuals,cables,calibration data,software,etc.are not included with this equipment unless listed in the above stock item description.All prices are shown in USD.
Siemens 6ES7221-1BF22-0XA8 Digital Input Module Specs
General
- Manufacturer Siemens
- Model 6ES7221-1BF22-0XA8
- Condition New Original ready stock
- Product Family
6ES7221-1BH22-0XA8,6ES7221-1EF22-0XA0,6ES7222-1BF22-0XA8
Important Notice:Other accessories,manuals,cables,calibration data,software,etc.are not
included with this equipment unless listed in the above stock item description.All prices are
shown in USD.
- Equipment-level signal acquisition: Used to connect to distributed devices such as sensors, limit switches, buttons, and photoelectric switches in the field.
- Modular machinery control: Commonly used in packaging machinery, assembly lines, material handling, and equipment linkage control in smart factories.
- System expansion: When the input points of the S7-22X CPU are insufficient, this expansion module increases I/O capacity.
- Input Voltage: Nominal 24V DC. Signal "0" is 0 to 5V, signal "1" is +15 to +30V.
- Input Current: Typical current for signal "1" is 4 mA.
- Low Power Consumption: Typical power consumption is only 2 W.
- Physical Characteristics: High shock and vibration resistance, with built-in overheat protection.
- Bidirectional Compatibility (Sink/Source): The module supports both sink and source wiring, allowing for flexible adjustment based on the type of field sensors without requiring hardware replacement.
- Address Management: In STEP 7-Micro/WIN software, the expansion module's I/O addresses are typically automatically allocated in 8-bit (1 byte) groups.
- Response Characteristics: Features a typical response latency of approximately 30ms, ensuring stable reception of control commands.