This fast acting overspeed protection device is designed to be applied in conjunction with a turbine control or trip system to safely shut down the turbine in the case of a turbine overspeed event. Interface with related control systems or plant DCS(s) (Distributed Control Systems) can be performed via the ProTech-GII’s redundant hard-wired input and output signals or through its triple-redundant serial Modbus communications ports.
On-line Testing
- Each ProTech-GII module can be tested manually from the module’s front panel, Modbus communications port, or automatically via its auto-test routine function. The ProTech-GII allows users to configure an overspeed test to be performed automatically on a periodic basis, testing each module (A, B, C) one at a time, and logging the result of each test or halting the test for a sensed error.
Trip, Alarm, & Overspeed Logs
- The ProTech-GII log function logs (saves to memory) all trips, alarms, trip valve response times, and overspeed events. The trip-log function uses a scrolling buffer and records the last 50 sensed trip or alarm events and the last 20 overspeed events to memory, with associated times. Each log file can be viewed from the unit’s front panel, or downloaded to a computer via the ProTech-GII service tool program. Each module utilizes non-volatile memory to ensure that all logged events are saved, even on loss of power.
Real Time Clock
- Each ProTech-GII module utilizes a real-time clock to ensure accurate time logging. A special timeaveraging function is utilized between modules to to ensure module-to-module clock synchronization.