Digital input module – Siemens SIMATIC SM421

The module Siemens SIMATIC SM421 This is a digital input module for SIMATIC S7-400 PLCs. It features 16 optocoupler-isolated 24 V DC inputs, ensuring reliable signal acquisition from industrial sensors and switches.

Optocoupled isolation for robust acquisition

Optocoupled isolation protects internal circuits from electrical interference from connected sensors. Therefore, this module is suitable for robust PLC architectures requiring reliable handling of field signals. Furthermore, its design ensures stable reading of digital inputs in demanding industrial environments. In addition, a faulty module will interrupt the acquisition of multiple signals simultaneously.

Part tested, available immediately

Having a tested replacement module allows for a quick restoration of signal acquisition. Therefore, our team checks each module before shipping. Furthermore, we guarantee its reliability from the first commissioning. We ship in secure packaging with tracking. For any inquiries, Our team is at your service..

Key points & details:

Model : SIMATIC S7-400 SM421 (6ES7 421-1BL01-0AA0)

Brand : Siemens

Kind : Digital Input Module (16 DI, 24 V DC, optocoupled isolation)

Function : Acquisition of digital signals from sensors and peripherals

Application : Industrial automation / SIMATIC S7-400 PLC systems

Weight : 1 kg

Shipping : Fast delivery via courier, secure and tracked shipping