ProTechTPS Total Protection System
Manual 26710V1
50
Woodward
Chapter 3.
Functionality
Introduction
The ProTechTPS is an overspeed safety device designed to safely shut down
steam, gas, and hydro turbines of all sizes upon sensing an overspeed or over-
acceleration event. This device accurately monitors turbine rotor speed and
acceleration via active or passive MPUs (magnetic pickups) and issues a
shutdown command to the turbine’s trip valve(s) or corresponding trip system.
The ProTechTPS includes all the functionality of the original ProTech 203
Overspeed Protection system, but adds additional inputs, outputs, protection
features, and configurable software to allow the ProTechTPS to meet the
requirements of a Total Protection System.
Depending on the system design, the ProTechTPS can be purchased with two
dual redundant trip relay outputs using a 2-out-of-3 voted architecture, or with
three independent non-voted trip relay outputs. Individual alarm relays, 4–20 mA
speed readouts, and Modbus communications make this overspeed device easy
to integrate into any turbine safety system.
Features
Fault Tolerant Design
Each ProTechTPS consists of three independent modules referred to as A, B
and C. Each module accepts one speed input, ten configurable analog / discrete
inputs, and three dedicated-function discrete inputs. Each module also has three
configurable relay outputs and one analog output for the sensed speed output.
The ProTechTPS comes in two basic models – the “Independent Trip Relay”
models and the “Voted Trip Relay” models. This relates to the trip signal
configuration. The differences between these two models and their application
are discussed in detail in the Product Models section of this chapter. Each of the
three ProTechTPS modules A, B, and C are fully fault isolated from each other,
so that faults in one module do not affect other modules. The modules are
connected via a safety certified CAN network which allows the sharing of all
module input information (speed, acceleration, analog/discrete inputs, and
dedicated-function discrete inputs) and module configuration information. The
ProTechTPS’s configuration copy function also utilizes this network to
transfer/copy configuration data from one module to another.
Normally, each module is configured to operate the same exact application
program and with the same exact configuration settings. Monitoring logic is used
to validate that all modules are running the same exact application program as
the other modules, and the monitoring logic will issue an alarm if it detects that
one or more of the modules are not running the exact same application program.
Thus if program changes are downloaded to a module, or a change to
configuration setting is made to one module, while the ProTechTPS is in normal
operation and the turbine or equipment is on-line and operating normally, each
module will issue an alarm. Once all application programs are the same again
and all configuration settings are the same again, this alarm can be reset.
