Model Number Breakdown:

• F3SP: F3 Safety PLC series
• 76: CPU type designation — standard CPU, 7-slot rack
• 7S: 7 slots, Standard (non-redundant) configuration

Key Specifications:

• Safety Integrity Level: SIL 2 (SFT) and SIL 3 (HFT) certified per IEC 61508 Ed.2
• CPU Type: 32-bit RISC processor
• Program Memory: 512 KB (user program)
• Data Memory: 2 MB RAM
• I/O Capacity: Up to 64 I/O points (digital and analog combined) across 7 slots
• Scan Time: ≤ 50 ms (typical, depends on program complexity)
• Communication: F Safety Bus (FSB) — proprietary Yokogawa safety communication protocol
• Redundancy: Non-redundant (simplex) in -7S configuration; redundant variants available (-7R, -7D)
• Operating Temperature: -20 °C to +70 °C (extended range)
• Power Supply: 24 V DC (redundant dual supply supported)
• Power Consumption: ≤ 8 W (CPU only)

Functional Features:

• Safety Logic Execution: Supports ladder logic, function block diagram (FBD), and structured text (ST) per IEC 61131-3
• Online Program Modification: Logic can be modified and downloaded while the system remains in safe state (with restrictions)
• Diagnostic Coverage: ≥ 99% for CPU, memory, and I/O modules
• Watchdog Timer: Hardware watchdog with 100 ms timeout
• Self-Test: Periodic power-on self-test (POST) and runtime diagnostic scan
• Event Logging: Up to 10,000 events stored in non-volatile memory with timestamp accuracy of ± 1 ms
• Fail-Safe I/O: All digital I/O modules are energized-to-trip (de-energized = safe) or de-energized-to-trip configurable

Material Composition:

• Housing: Die-cast aluminum alloy with anodized finish (corrosion-resistant)
• PCB: Multi-layer FR-4 with gold-plated contacts for high reliability
• Connectors: Locking D-sub connectors for I/O bus; M12 circular connectors for field wiring
• Front Panel: Polycarbonate with UV-resistant coating

Structural Characteristics:

• Form Factor: 7-slot rack-mountable chassis (DIN rail or panel mount)
• Dimensions: 482.6 mm (W) × 220 mm (H) × 250 mm (D) (with 7 slots populated)
• Weight: Approximately 4.5 kg (empty chassis with CPU)
• Slot Configuration: 1 CPU slot + 6 I/O slots (mix of digital/analog/communication)

Operating Principle:
The F3SP76-7S continuously executes the safety logic program stored in its non-volatile memory. Input signals from safety-rated field devices (e.g., emergency stop buttons, flame detectors, pressure switches) are scanned every ≤ 50 ms. The CPU evaluates the logic and drives safety-rated output modules to activate final elements (e.g., solenoid valves, motor starters). The F Safety Bus (FSB) provides a dedicated, deterministic communication channel between the CPU and I/O modules, ensuring no interference from non-safety network traffic. All safety functions are executed in a triple modular redundancy (TMR) or dual-channel voting architecture internally to achieve the required SIL rating.

Advantages & Highlights:

• Dual SIL Certification: Certified to both SIL 2 and SIL 3 from a single hardware platform — reduces spares inventory
• Fast Scan Time: ≤ 50 ms cycle time ensures rapid response to hazardous conditions
• High Diagnostic Coverage: ≥ 99% detection of internal faults minimizes undetected dangerous failures
• Seamless DCS Integration: Communicates with CENTUM VP/CS 3000 via F Fieldbus for non-safety data exchange

Applicable Industries:

• Oil & Gas (Upstream/Midstream/Downstream)
• Chemical & Petrochemical Plants
• Nuclear Power (BOP systems)
• Pharmaceutical Manufacturing
• Mining & Minerals Processing

Installation Requirements:

• Mount in a NEMA 4 / IP65 rated enclosure in hazardous areas (Zone 1 / Zone 2 or Class I Div. 1 / Div. 2)
• Use safety-rated (SIL-certified) field devices only; do not connect non-safety devices to safety I/O
• Provide redundant 24 V DC power supply (dual-channel) for maximum availability
• Maintain minimum 100 mm clearance above and below the chassis for airflow
• Ground the chassis to the plant earthing system with ≤ 1 Ω resistance

Usage Precautions:

• Never modify safety logic without a formal Management of Change (MOC) procedure and safety review
• Do not mix safety I/O and standard I/O on the same backplane — use dedicated F3SP safety chassis
• Perform proof testing at intervals defined by the Safety Requirements Specification (SRS) — typically every 6 to 12 months
• Do not operate the unit in ambient temperatures exceeding +70 °C
• All field wiring must use shielded cable with shield grounded at the controller end only