ABB DO821 Key features
High Isolation: Individually isolated channels (250 V insulation) ensure reliable operation in noisy environments.
Wide Voltage Support: Handles 5–250 VAC/DC, adaptable to both AC and DC actuators.
Fast Response: ≤ 9 ms pick-up and ≤ 5 ms release times meet tight control requirements.
Robust Mechanical Design: Durable relays rated for >20×10⁶ mechanical and >1×10⁶ electrical operations.
Simple Diagnostics: Front-panel LEDs for module, warning, fault, and per-channel status expedite troubleshooting.
Integration: Seamlessly fits S800 I/O racks with TU8xx MTUs, simplifying rack wiring.
Typical cooperation cases
Process Automation: Drives solenoid valves and actuators in chemical, petrochemical, and pharmaceutical plants.
Power Generation: Controls cooling fans, breaker coils, and turbine tripping circuits in power stations.
Water & Wastewater: Manages pump start/stop commands, valve actuators, and warning indicators in treatment facilities.
Building & Infrastructure: Interfaces with HVAC dampers, lighting controls, and emergency alarm systems.
