Siemens 6ES7221-1BF22-0XA0 8-Point Digital Input Module | Replacement, Equivalent & Selection Guide
Technical Specifications
- Part Number: 6ES7221-1BF22-0XA0
- Series: SIMATIC S7-200 Expansion Module EM221
- Manufacturer: Siemens AG
- Module Type: Digital Input (DI)
- Number of Inputs: 8 × DC 24V digital inputs
- Input Voltage: 24 VDC (nominal)
- Input Current: 4 mA per channel (typical)
- Isolation: Optocoupler isolation, 500 VAC
- Input Delay: 0.2 ms / 6.4 ms (selectable)
- Connector Type: Removable screw terminal
- Power Consumption: 5 VDC bus: 30 mA; 24 VDC: 40 mA (no load)
- Dimensions (W×H×D): 46 × 80 × 62 mm
- Weight: Approx. 130 g
- Operating Temperature: 0 °C to +55 °C
- Storage Temperature: −40 °C to +70 °C
- Protection Rating: IP20
- Certifications: CE, UL, cUL, FM
Compatible Replacement & Equivalent Models
The following models are commonly evaluated as replacements or equivalents for the 6ES7221-1BF22-0XA0. Always verify electrical and mechanical compatibility before substitution.
- 6ES7221-1BH22-0XA0 — EM221, 16DI × 24VDC (expanded channel count alternative)
- 6ES7221-1BF32-0XA0 — Newer firmware revision; functionally equivalent, check CPU compatibility
- 6ES7221-1BH32-0XA0 — 16DI version of the -32 revision series
- 6ES7223-1BF22-0XA0 — EM223 8DI/8DO combo module (if output expansion is also needed)
- 6ES7223-1BH22-0XA0 — EM223 16DI/16DO combo module
- Third-party compatible: Yaskawa, Delta DVP-08SM11N, Mitsubishi FX2N-8EX (verify bus protocol before use)
Why Choose the Original Model
- Guaranteed compatibility with all S7-200 CPUs (CPU 221/222/224/224XP/226)
- Siemens factory-tested and certified — no firmware mismatch risk
- Full STEP 7-Micro/WIN software support with auto-recognition
- Consistent optocoupler isolation quality for noise-sensitive environments
- Backed by Siemens global warranty and long-term spare parts availability
- Traceable manufacturing batch for compliance and audit requirements
Typical Applications
- Machine tool control — limit switch and proximity sensor signal acquisition
- Conveyor and material handling — start/stop and position detection
- Packaging machinery — product counting and jam detection
- HVAC and building automation — status monitoring of contactors and valves
- Water treatment — pump run/fault feedback and level switch inputs
- Food & beverage — hygienic sensor integration with IP20 panel mounting
System Compatibility
- Compatible CPUs: S7-200 CPU 221, CPU 222, CPU 224, CPU 224XP, CPU 226
- Max Expansion Modules per CPU: Up to 7 (CPU 224/226); up to 2 (CPU 222)
- Bus Interface: S7-200 proprietary I/O expansion bus (not compatible with S7-300/400/1200/1500)
- Programming Software: STEP 7-Micro/WIN V4.0 SP9 or later
- Communication: Module is passive — no independent communication port
Selection Guide
Use the table below to select the correct EM221 variant for your application:
- 8 inputs, 24VDC → 6ES7221-1BF22-0XA0 ✓ (this model)
- 16 inputs, 24VDC → 6ES7221-1BH22-0XA0
- 8 inputs, 120/230VAC → 6ES7221-1EF22-0XA0
- 16 inputs, 120/230VAC → 6ES7221-1EH22-0XA0
- Need mixed DI/DO → Consider EM223 series (6ES7223-xxx)
- Need analog input → Consider EM231 series (6ES7231-xxx)
Tip: If your CPU 222 is already at 2 expansion modules, consider upgrading to CPU 224 to accommodate additional EM221 modules.
Quality Assurance & Sourcing
- All units sourced from authorized Siemens distribution channels or verified surplus with full traceability
- Pre-shipment inspection: visual, label verification, and functional power-on test
- Anti-static packaging with humidity indicator card
- Batch documentation and certificate of conformity available on request
- Konmask.com specializes in industrial automation components for B2B buyers globally
How to Order
- SKU / Part Number: 6ES7221-1BF22-0XA0
- Minimum Order Quantity: 1 piece
- Lead Time: In-stock items ship within 1–3 business days; contact us for bulk order scheduling
- Payment: T/T, PayPal, credit card via Shopify Payments
- Shipping: DHL / FedEx / UPS worldwide; sea freight available for large orders
- RFQ / Bulk Inquiry: support@konmask.com | +0086 19859288691
Replacement & Compatibility FAQ
Q: Can I use 6ES7221-1BF32-0XA0 instead of 6ES7221-1BF22-0XA0?
A: The -32 revision is functionally equivalent for most applications. Verify your CPU firmware version supports the newer revision via STEP 7-Micro/WIN compatibility notes.
Q: Is this module compatible with S7-1200 or S7-300?
A: No. The EM221 uses the S7-200 proprietary expansion bus and is not compatible with S7-300, S7-400, S7-1200, or S7-1500 systems.
Q: Can third-party 8DI modules replace this unit?
A: Some third-party modules claim S7-200 bus compatibility, but Siemens does not certify these. Use at your own risk; original Siemens modules are strongly recommended for production environments.
Q: What is the difference between EM221 and EM223?
A: EM221 provides digital inputs only. EM223 provides a combination of digital inputs and digital outputs in a single module — choose EM223 if you need both I/O types in one slot.
Q: Do you provide a warranty?
A: Yes. All new units carry the standard Siemens warranty. Refurbished units carry a 90-day Konmask.com functional warranty. Contact us for details.
© 2026 Konmask.com. All rights reserved.
Original Source: https://Konmask.com
Contact: support@konmask.com | +0086 19859288691
