The Woodward ProTech-GII is an IEC 61508 SIL-3 certified overspeed protection device designed to safely shut down steam, gas, and hydro turbines upon sensing an overspeed or over-acceleration event. Its 12 millisecond response time, 0.5 to 32,000 rpm speed range, and triple-modular architecture with online testing and repair capability give it one of the highest availability and reliability ratings in the industry.
Key Features
Protection
- IEC 61508 SIL-3 certified safety device
- 12 millisecond total response time
- Speed range: 0.5 to 32,000 rpm
- Overspeed and over-acceleration detection
- Active or passive MPU (magnetic pickup) speed inputs
- Two dual-redundant trip relay outputs (2-out-of-3 voted), or three independent non-voted outputs
- Individual alarm relays and 4–20 mA speed readouts
Reliability & Integration
- Triple-modular architecture (A, B, C modules)
- Online testing and online repair capability
- Dual power inputs: high-voltage (90–240 Vac / 100–150 Vdc) or high + low voltage (18–32 Vdc)
- High-signal-select power: operates with either or both sources
- Triple-redundant serial Modbus communications
- Optional Ethernet gateways for plant network integration
- Flush-mount or bulkhead-mount models
- IP56 ingress protection for harsh environments
Applications
- Steam, gas, and hydro turbine overspeed protection
- Critical turbomachinery safety systems (IEC 61508 / IEC 61511)
- Simplex or dual-redundant trip block assemblies
- 2-out-of-3 voted trip systems
- Paired with QuickTrip trip block and ProTech-TPS logic solver
Drake Controls Services
Drake Controls is a Woodward Authorized Distributor. We stock ProTech-GII units and provide installation support, configuration, and repair. The ProTech-GII is a core component of Drake turbine safety system packages alongside the QuickTrip trip block and ProTech-TPS logic solver.