Module overview
The Siemens 6ES7521-7EH00-0AB0 is a digital input module for the S7-1500 system, supporting both source/sink inputs and motion-sensing interface (MSI) inputs. Diagnostic alarm, hardware interrupt, and prioritized startup are included. Firmware version V1.0.0 is field-updatable.
Input voltages and signal thresholds
Rated for 24 V, 48 V, and 125 V in both AC (50-60 Hz) and DC variants. Signal '0' spans -5 to +5 V; signal '1' requires +11 to +146 V. Typical input current at 24 V DC is 3 mA. Wire-break detection triggers below 550 µA.
Lifecycle and sourcing
Marked as current production. Firmware V1.0.0 includes I&M data (I&M0–I&M3). Available to order against RFQ.