Brand: Siemens
Part No: 6ES7421-1BL01-0AA0
Type: Digital Input Module SM421
System: Simatic S7-400
Condition: New Factory SealedThe Siemens 6ES7421-1BL01-0AA0 is a digital input module SM421 compatible with the SIMATIC S7-400 system, providing isolated 32 digital inputs at 24 V DC. This module supports industrial automation applications requiring precise digital input handling within control systems.
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✓ Ships within 24 hours from stock
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✓ Worldwide insured shipping via UPS & DHL
✓ Includes 30-day warranty

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We supply industrial automation spare parts including PLCs, HMIs, CPUs, I/O modules, drives, sensors, and control components from leading brands such as Siemens, Beckhoff, Allen-Bradley, Omron, Schneider Electric, Eaton, and more. All parts are available from stock and ready for fast worldwide shipping. Aegean Automation is a trusted supplier of industrial automation components for production systems, machinery, and factory automation worldwide.
This product is used in industrial automation systems to support reliable operation and integration within control and monitoring environments.
It is commonly applied in PLC systems, control panels, and automation processes where stability and long-term performance are required.
Suitable for maintenance, replacement, or expansion of existing industrial automation systems.


















