Honeywell FC-SDI-1624M Safe Digital Input Module

Certified Safety Input Processing

The FC-SDI-1624M provides 16 fail-safe digital input channels for the Honeywell Safety Manager system. This module complies with SIL 3 and IEC 61508 standards for functional safety applications. It accepts 24 VDC nominal inputs with a wide tolerance range of 18–30 VDC . The module’s dual-channel architecture ensures failsafe operation for emergency shutdown and fire and gas systems. Therefore, it delivers dependable signal acquisition in the most critical process safety loops.

Redundant Architecture and Fault Tolerance

The FC-SDI-1624M utilizes a 1oo1 architecture for each channel but maintains dual microprocessor paths for diagnostics. This design generates a safe state when it detects any internal or external fault condition . The module performs extensive self-tests every 200 milliseconds to validate input circuitry integrity. Moreover, it actively monitors open circuits and short circuits on each field connection . This comprehensive diagnostic coverage ensures the module achieves the required probability of failure on demand (PFD) for SIL 3 compliance.

Smart Field Power Management

The module supplies a regulated 24 VDC field power output to energize connected field sensors . Current-limiting and overvoltage protection circuits safeguard the module and the field devices from electrical faults . Each input channel draws approximately 6 mA when active, minimizing power consumption. The module also supports redundant field power inputs for enhanced system availability .

Technical Specifications