WOODWARD ® ProTech‐SX Safety System with Integrated Overspeed Protection

WOODWARD ® ProTech-SX Safety System with Integrated Overspeed Protection

Description

The ProTech-SX ("ProTech Simplex") is a safety PLC (programmable logic controller) with integrated overspeed protection designed to safely shut down any plant process equipment, engine, or steam, gas, or hydro turbine upon sensing a safety event. This stand-alone safety system accepts two speed inputs and seven discrete/analog inputs, uses programmed logic to determine when a safety event has occurred, then issues system shutdown commands and alarms. The ProTech-SX uses five fastacting, configurable relay outputs and a speed meter output to interface with/command protection to the specific system or device.

Designed to safely protect high-speed rotating equipment in system-critical applications, this safety PLC’s total response time is less than 12 milliseconds. Programmable inputs and outputs, a 4–20 mA speed readout, and Modbus® * communications make this device easy to integrate into any plant, engine, or turbine safety system.

The ProTech-SX is available in a flush-mount model designed to be installed within a panel or cabinet door located in a control room or on the turbine skid. Designed for harsh environments when installed within an enclosure, this device has an ingress protection rating of IP56 (protected against dust and completely protected against jets of water of similar force to heavy seas).

Depending on the model ordered, the ProTech-SX accepts either two high-voltage power inputs (90–240 VAC / 100–150 VDC) or one high-voltage power input (90–240 VAC / 100–150 VDC) and one low-voltage power input (18–32 VDC). This design works on a high-signalselect basis, allowing the unit to fully operate with either or both power sources available. *—Modbus is a trademark of Schneider Automation Inc.

Applications

The ProTech-SX safety system is designed to be applied as a safety system for small engines, steam, gas, or hydro turbines, or related plant systems. This safety PLC’s fast (12 millisecond) response time, 0.5 to 32 000 rpm speed range, and integrated overspeed and acceleration detection/protection functionality, make it ideal for application on all types and sizes of turbines or engines.

Alternatively, this stand-alone safety device can be configured to protect any plant system or device, and report the system’s/device’s status to the plant DCS. The ProTech-SX’s versatile inputs, outputs, programming environment, and communications make it ideal as a safety protection device for use in small applications that could possibly reach an unsafe state or condition and that must communicate directly to the plant DCS.

The ProTech-SX is designed for critical applications where both personnel safety and unit availability (operation run time) is a concern or necessity. Certified as an IEC61508 SIL-2 (Safety Integrity Level 2) safety device, the ProTech-SX can easily be applied as a standalone IEC61508-based device or within an IEC61511-based plant safety system. A thorough product manual is provided to instruct users on how to apply the ProTech-SX to meet IEC based requirements.

The ProTech-SX’s high-end functionality, like first-out trip indication, alarm & trip logs, valve response monitoring, and programmable auto-test routines, coupled with its cost-effective price, make it useful as a safety device, as a cost effective speed switch (four programmable relays), or as a valve health monitor.

Interface with related control systems or plant DCS’s (Distributed Control Systems) can be performed via the ProTech-SX’s hard-wired inputs and outputs or through its serial Modbus communication port. Optionally, an Ethernet gateway can be purchased to easily interface with a plant Ethernet network.

Functionality

Programming—The ProTech-SX functions as a safety PLC, as it accepts seven discrete or analog inputs, and allows users to create custom safety/protection programs to protect site personnel and equipment. Programmers are able to utilize typical logic and testing sequence routines to create their application-specific safety logic and tests.

On-Line Testing—The ProTech-SX can be tested manually from the module’s front panel, Modbus communications port, or automatically via its auto-test routine function. The ProTech-SX allows users to configure overspeed or customprogrammed manual or automatic performance tests.

Trip, Alarm, & Overspeed Logs—The ProTech-SX 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 is viewed from the unit’s front panel, or downloaded to a computer via the ProTech-SX service tool program. Each module utilizes non-volatile memory to ensure secure capture of all logged events, even on loss of power.

Trip Valve Health Monitoring—The ProTech-SX can be configured to test, log, and alarm on the response time of a turbine trip valve. Using the trooper’s built-in valve response monitoring function, users can connect a valve position sensor (limit switch, pressure switch) to a ProTech-SX input and configure the ProTech-SX to monitor, log, and alarm the period between sending a trip command and receipt of a valve-closed indication.