GE MARK VI

7/22/2019 GE MARK VI

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GE Energy

Mark VI for Gas Turbine Control Retrofits

Application OverviewThis document is distributed for informational purposes only.It is not to be construed as creating or becoming part of anyGeneral Electric Company contractual or warranty obligationunless expressly stated in a written sales contract.

!2002 - 2005 by General Electric Company, USA. All rights reserved.

GEI-100538A


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Section Page

Introduction .................................................................................................................3Acronyms and Abbreviations ......................................................................................3Product Options...........................................................................................................4Architecture.................................................................................................................6I/O Interface.................................................................................................................8

Diagnostics ................................................................................................................10Communication .........................................................................................................10Control Functions ......................................................................................................12HMI ...........................................................................................................................16Typical Turbine Instrumentation...............................................................................18Packaging ..................................................................................................................19Typical Power Requirements.....................................................................................20

Ethernet is a registered trademark of Xerox Corporation.CIMPLICITY is a registered trademark of GE Fanuc Automation North America, Inc.Microsoft and Windows are registered trademarks of Microsoft Corporation.

Modbus is a registered trademark of Schneider Automation.Proximitor is a registered trademark of Bently Nevada.


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IntroductionMost existing transmitters,

sensors, and switches arecompatible with the Mark

VI I/O, and, in some cases,

the I/O is totallycompatible.

The Mark VI is a fully programmable gas turbine controller with its own power

supply, processor, communications, and I/O for turbine control, and protection.

Critical functions, such as emergency overspeed, redundant exhaust over-temperature protection, and backup synchronous check protection are provided by

the backup protection module.

Application software is derived from current control and protection algorithms,

originally designed for new gas turbines, and modified only where it is necessary for

compatibility with the existing site conditions. In addition, the controller has thespeed and capacity to implement many new advanced features such as Dry Low

NOx technology. All Mark VI controllers are shipped with application software and

display software.

Acronyms and Abbreviations

ADL Asynchronous Drives Language

DCS Distributed Control System

EGD EthernetGlobal Data

FSR Fuel Stroke Reference

GSM GE Standard Messages

GUI Graphical User Interface

HMI Human-Machine Interface

LVDT Linear Variable Differential Transformer

PDH Plant Data Highway

rms root mean square

RTD Resistance Temperature Detector

TMR Triple Modular Redundant

UDH Unit Data Highway

UPS uninterruptible power supply

VME VERSA module Eurocard

GEI-100538A Mark VI for Gas Turbine Control Retrofits 3


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Product OptionsThe Mark VI controller is available in two state-of-the-art types: simplexand Triple

Modular Redundant (TMR). These vary in cabinet size and I/O configuration

based on the turbine type, application (generator or mechanical drive), and I/Orequired at a particular site.

A simplex controller is available in two sizes:

36x 36 (900 mm x 900 mm), which fits into the standard Mark I or Mark IIcontroller footprint

54x 36 (1350 mm x 900 mm), which fits into the standard Mark II with ITS

controller footprint. This version also provides increased I/O capacity, as well asa redundant VME rack-power supply.

The standard size of the TMR unit is 54x 36 (1350 mm x 900 mm), which fits intothe standard Mark IV controller footprint (refer to the following diagram).

4 Mark VI for Gas Turbine Control Retrofits GEI-100538A Application Overview


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P

S

Control Module

X

P

S

Y

P

S

Control Module

Z

Control Module

Protection Module

Emergency Overspeed

Emergency Overtemp

Backup Synch Check

Control

Protection

Monitoring

Communication from Control Module:

Serial Modbus Slave

Serial Modbus Master

Ethernet TCP-IP Modbus Slave

Ethernet UDP-IP (UDH)

Additional

Communications(if required)

Devices on UDH:HMI, EX2000, Mark VI

P.S.

CPU

I/O

P.S.

CPU

I/O

P.S.

CPU

I/O

Ethernet - IONet

Ethernet - IONet

Ethernet - IONet

AdditionalCommunications

(if required)

TMR only

System Architecture



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ArchitectureScalable hardware and software make the Mark VI architecture well-suited for gas

turbine control retrofits.

A TMR system is generally

recommended for base load,DLN, and cogen

applications.

The TMR and simplex versions of the Mark VI controller have equivalent control

and turbine protection capabilities. The primary difference is running reliability.Running reliability is based on the percent of I/O used in the system, the percent of

I/O classified as critical, and the amount of redundancy.

TMR systems have the highest running reliability, represented by a longer Mean

Time Between Forced Outage (MTBFO) than other types of controllers.

Select a TMR system when:

Co-generation (cogen) plants where the gas turbine exhaust is the only source of

heat to generate steam for the production process and steam turbines

Turbines are equipped with triplicated field devices, for maximized runningreliability

Dry Low NOx (DLN) combustion system upgrades, where instrumentationstandards often require more replicated field devices than standard combustion

systems

Generator drive applications that require continuous base-load operation

Mechanical drive applications where compressors or pumps are critical to theproduction process

Select a simplex system when:

Using non-base load applications that are not critical to other plant processes

Customer operating experience indicates this system is adequate



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s

Mark VI Simplex 36" by 36" Cabinet



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I/O InterfaceTerminations support the

existing #12 AWG (3.0mm2) wires at site with

barrier type terminal blocks

or ease ofmaintenance.

The Mark VI is designed for direct interface to turbine and generator devices such as

vibration sensors, flame scanners, linear variable differential transformers (LVDT),

magnetic speed pickups, thermocouples, and resistance temperature detectors(RTD). Direct monitoring of these sensors reduces the need for interposing devices

with their associated single-point failures. Direct connection to a field device reduceslong-term maintenance, and enables diagnostics to directly monitor the health of

devices mounted on the machinery.

Contact inputsare normally powered from the 125 V dc battery bus (optional 24and 48 V dc) through the Mark VI termination boards. Each contact input is optically

isolated and has a 1ms time stamp for Sequence of Events (SOE) monitoring.

Terminations for existing contact inputs can be replaced 1-for-1 or split up for

greater alarm resolution. For example, instead of having several field contacts wired

to a single contact input for theLube System Troublealarm on the enunciatorwindow, they can be separated into multiple contact inputs to provide a separate

alarm message for each problem in the lube oil system.

Diagnostics monitor the

secondary side of each fuse.Contact outputsare from plug-in, magnetic relays with dry, Form-C, contact

outputs. Turbine solenoids are normally powered from the 125 V dc battery bus with

suppression for each solenoid with a 3.2 A slow-blow fuse on each side of the feeder

circuit.

Analog inputsmonitor 4 20 mA (250 ), which can be configured for self-powered, differential inputs, or as sensors that use a +24 V dc supply from the Mark

VI. Selected inputs can be configured for 0 1mA inputs (5,000 ) or 5, 10 V dc

inputs. This interfaces to

existing 0 1mA generator MW and MVAR transducers

existing Dynesco-type gas fuel pressure and compressor discharge pressure

transducers with 12 V dc supply and 0 5 V dc inputs

Most Mark II generator drive systems already have these transducers; however,

Mark I systems do not. Compressor discharge pressure biases the temperaturecontrol system to improve turbine operation.

Analog outputscan be configured for 4 20 mA output (500 maximum) or 0

200 mA output (50 maximum).

Thermocouple inputscan be grounded or ungrounded. Software linearization is

provided for type J and K thermocouples used on GE gas turbines plus types E, S, orT thermocouples. Existing control and overtemperature thermocouples are retained

and divided between the Mark VI controller and the backup protection module for

temperature control and overtemperature protection, respectively.

RTD inputs can be grounded or ungrounded. Software linearization is provided for

10 copper, 100/200 platinum, or 120 nickel RTDs. The generator or load

compressor RTDs can be monitored directly by the Mark VI with all turbine anddriven-load temperatures being collected in a common database with other turbine-generator parameters.



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Speed inputs.Redundant, passive, magnetic speed sensors provide an input to the

control module(s) for speed control and overspeed protection. Emergency overspeed

protection is provided electronically; mechanically on older turbines. A separate

backup protection module is provided with separate power supplies, processors, and

I/O cards to provide enhanced machine protection. Overspeed detection by either theprimary or emergency electronic trip systems or the mechanical overspeed bolt

automatically de-energizes the hydraulic solenoids.

Flame inputs.A direct interface is provided for ultra-violet flame scanners that

produce a pulsed output. This eliminates any interposing transducers and enables the

diagnostics to monitor the actual light level. An alarm is initiated if the light leveldiminishes below an acceptable level due to carbon or other deposits on the scanner

window.

Integrating servo interface. The Mark VI provides a direct interface to the bipolar

servo actuator and LVDT valve position feedback. Bi-polar integrating servo current

outputs are provided in 10, 20, 40, 80, and 120 mA ranges for fuel valves and InletGuide Vane (IGV) control. Mark VI LVDT excitation is 7.0 Vrms at 3.2 kHz. Pulse

rate inputs are also provided for servo control loops using liquid fuel-flow, pulse-rate

feedback.

Vibration protection.A direct interface is provided for vibration protection sensors,which are required to trip the turbine. This includesseismic (velocity) type sensors

used on heavy-duty gas turbines and accelerometerson aircraft-derivative gasturbines. This eliminates the single-point failure of a separate monitoring system, and

allows Mark VI diagnostics to monitorseismic sensorswhen the turbine is runningor stopped. Aircraft derivative applications primarily use accelerometers,which

produce a velocity signal from external charge amplifiers. The Mark VI contains

speed-tracking filters to isolate the appropriate vibration frequencies of each shaft for

the display, alarm, and trip.

Proximitor

monitoring provides monitoring and protection for GE gas-turbine

applications. Mark VI provides a direct interface to the keyphasor, radial proximitor,

and axial proximitor inputs, which are collected in a common database with turbineparameters. The fundamental (1X), first harmonic (2X), and composite vibration

signals are collected by the Mark VI and displayed with both magnitude and phaseangle on the Human-Machine Interface (HMI). Active isolators provide buffered

outputs to BNC connectors on the Mark VI termination boards for temporary

connection to portable analysis equipment.

The PTs are paralleled to

the backup protectionmodule for redundant

backup synch check

rotection.

Synchronizing interfaceincludes one generator PT and one line PT to match the

generator frequency (turbine speed) to the line frequency and match the generator

voltage to the line voltage through commands to the generator excitation control.The Mark VI monitors actual breaker closure time and self-corrects each time the

breaker closes.



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DiagnosticsMark VI diagnostics include power-up, background, and manually initiated

diagnostic routines capable of identifying both control panel, sensor, and output

device faults. These faults are identified down to the VME board and terminal boardlevel for the panel, and to the circuit level for sensors and actuators.

CommunicationThe Mark VI uses the following communication networks.

I/O Netis an Ethernet-based network between a control module, the three

sections of the backup protection module, and expansion I/O modules (if

required). I/O Net uses Asynchronous Drives Language (ADL) topollthemodules for data instead of using the typical collision detectiontechniques used

in Ethernet LANs.

Unit Data Highwat (UDH) is an Ethernet-based network that provides peer-to-peer communication between the Mark VI and a GE generator excitation

control. The network uses Ethernet Global Data (EGD), a message-based

protocol with support for sharing information with multiple nodes based on theUDP/IP standard. Data can be transmitted unicast or broadcast to peer

controllers on a network with up to 10 network nodes at 25 Hz.

Refer to the section, HMI,

or information on the user

interface.

The Mark VI can communicate to a GE HMI or directly with a plant Distributed

Control System (DCS) network or Plant Data Highway (PDH) through Ethernet

serial Modbus

slave/master, Ethernet TCP/IP Modbus slave, or Ethernet TCP/IP

with GE Energy Standard Messages (GSM).

GSM is only available from a Mark VI HMI; its protocol provides

Administration messages

Spontaneous event-driven messages (with local time tags)

Periodic group data messages at rates to one second

Common request messages



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EX2100

Unit Data Highway

Gas Turbine

Control

Mark VI

Generator

Excitation

Plant DCS

HMIOperatorStation

HMIOperatorStation

Ethernet TCP/IP GSMEthernet TCP/IP ModbusRS-232C/RS-485 Modbus

IRIG-B

Time Sync

Ethernet TCP/IPModbus

RS-232C/RS-485Modbus

Plant Data Highway

Ethernet UDP/IP

Typical Network for Mark VI and EX2100 with Direct Connect to DCS Option



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Control FunctionsThe control functions below are typical for a single-shaft generator drive application.

Nozzle control for two-shaft machines and load compressor controls are also

supported by Mark VI.

Startup controlis an open-loop system that increases the fuel stroke reference as theturbine startup sequence progresses to preassigned plateaus.

Acceleration controladjusts the fuel stroke reference according to the rate ofchange of the turbine speed to reduce the thermal shock to the hot gas path parts of

the turbine.

Speed controluses the median speed from three speed sensors for droop and

isochronous speed control with an automatic transfer to isochronous upon loss of the

tie-line breaker. Separate shaft speed-control algorithms are provided for each shaftin multi-shaft machine applications. The Mark VI varies shaft speed to control real

power (megawatt) output in a mechanical (compressor or pump) drive application. In

a generator drive application, the Mark VI maintains a constant generator shaft speedto meet the electrical power demand and also controls the generator field through the

use of VAR/Power Factor (PF) control algorithms to generate excitation raise and

lower commands.

Generator load controlcompares the load setpoint with the MW feedback from a

single-phase transducer and adjusts the speed setpoint to regulate the load. ASpinning Reserveselection allows the machine to start automatically and await an

operator input to synchronize to the grid. Selection ofFast Load StartorPre-

selected Loadraises the output to thePre-selected Loadsetpoint limit. Selection of

base or peak raises this setpoint to the maximum limit.

Exhaust temperature controlalgorithms sort the input from each thermocouple

from the highest to the lowest temperature. They automatically reject badthermocouple data, average the remaining data values, and execute the control

algorithm based upon the average calculated temperature. Redundant transducers

monitor the compressor discharge pressure and bias the temperature control to

correct for ambient conditions and the corresponding variations in mass flow.

Inlet guide vane controlmodulates the position of the compressor stator vanes toprovide optimum compressor and unit operation. During startup, the guide vanes

open as the turbine speed increases. When the unit is online, the guide vanes

modulate to control turbine airflow temperature to optimize combustion system and

combine-cycle performance.

Fuel control is a reference from the governor and feedback of the fuel controlvalves. The Fuel Stroke Reference (FSR) is determined by the turbine parameter

(speed, temperature, and so on) calling for the least fuel. FSR calculation occurs in

the main processor, then is transmitted to the servo valve cards on the backplane of

the control module(s). Liquid fuel control establishes the FSR of the bypass valve.

Fuel flow is proportional to the speed (Fuel Flow = Speed X FSR). Gas fuel control

uses a Gas Control Valve (GCV), where fuel flow is a function of pressure (FuelFlow = Fuel Pressure X FSR). An added Stop/speed Ratio Valve (SRV) opens as a

turbine speed function, so pressure becomes a function of speed and the liquid fuel

control system and the gas fuel control systems have the same characteristic.



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Emissions controlis available with diluent (water or steam) injection through a

multi-nozzle quiet combustor to quench flame temperature and reduce thermal NOx

formation. Lean-burning, pre-mixed flame combustors are available for lower NOx

levels without the need for water or steam injection called Dry Low NOx (DLN).

Load compressor controladjusts the turbine power output (speed) and providesvalve sequencing and surge control to optimize compressor operation.

Generator excitation controlfor voltage matching during synchronization andVAR/PF control after breaker closure can be integrated into the turbine control.

When a reference or setpoint is entered, feedback from a single-phase VAR

transducer regulates the setpoint in the Mark VI. Mark VI calculates PF from MWand MVAR inputs, or an external PF transducer can be connected to the Mark VI.

Setpoints are transmitted from the turbine control to the generator excitation control.

Gas Fuel

Servo

90SR

LVDT

96SR

TSVO

Stop/Speed

Ratio Valve

Termination

BoardVSVO Card

A/D

VCMICard

Main Processor

FPRG

TNH (Speed)

Constants

LogicSoftware

RegulatorD/A

96FG

Gas Fuel

PressureTBAIVAIC Card

D/A

+

-

Servo

65GC

LVDT96GC

TSVO

Gas Control

ValveVSVO Card

A/D

FSROUT

FSR2

LogicSoftware

RegulatorD/A

Combustion

Chamber

Servo65FP

TSVO

Stop/Speed

Ratio Valve

VSVO Card

A/D

SoftwareRegulator

Flow

Divider

Liquid Fuel

Pulse

77FD

D/A

FSROUT

Logic

TNH (Speed)

FSR1

FuelSplitterFSR

Logic

Control Module

Typical Dual Fuel Control System



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Sequencing

Turbine control can include automated startup and shutdown sequences customized

to meet operator requirements, as well as control and monitoring of all gas turbine

auxiliary and support systems. Operators can have the turbine automatically

sequence to intermediate hold points by selecting Crank,Fire, orAutowithout

enabling automatic synchronization. All ramp rates and time delays are pre-programmed for optimum performance. Timers and counters record long-term

turbine operating information that can include:

Total fired time

Separate DLN operating mode timers

Manually initiated starts

Total starts

Fast load starts

Fired starts

Emergency trips

This automation enables gas-turbine operation from a remote site with the assurancethat the turbine fully protected. Diagnostics capture a record of any abnormal

conditions.

Protection

Turbine control monitors all control and protection parameters and initiates an alarm

if an abnormal condition is detected. If the condition exceeds a predefined trip level,

the turbine control drives the gas/liquid control valves to a zero-flow position and de-

energizes the fuel shut-off solenoids. All control, protection, and monitoringalgorithms are contained in the control modules for efficiency in sharing common

data. The protection module includes standard backup turbine protection that meets

OEM tripping reliability requirements for turbine overspeed, overtemperature, andsync-check protection.

In a typical installation, a trip solenoid is powered from the 125 V dc floating batterybus with:

Contacts from the control module in series with the negative side of the bus

Contacts from the backup protection module in series with the positive side ofthe bus

Additionally, diagnostic and

trip data is communicated

between the control moduleand the backup protection

modules on the triple

redundant I/O Nets forcross-tripping.

Diagnostics monitor:

Contact from each relay

Voltage directly across the trip solenoid

Overspeed protection includes a primary overspeed monitoring system in the threecontrol modules and an emergency overspeed monitoring system in the backup

protection module that replaces the mechanical overspeed bolt used on older

turbines. The control module and each section of the backup protection module

monitors magnetic speed sensors from 2.0 rpm on a 60-tooth wheel. Diagnostics

monitor the speed and acceleration, then exchange the data between the controlmodule and the protection module on startup to verify that all sensors are active.



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Typical gas turbine trip protection system

Trips Types

Pre-ignition Auxiliary check (Servos)

Seal oil dc motor undervoltage

dc lube oil pump undervoltageStartup fuel flow excessive

Failure to ignite

Post-ignition Loss of flame

High exhaust temperature

Exhaust thermocouples open

Compressor bleed valve position trouble

Load tunnel temperature high

Gas fuel hydraulic pressure low

Turbine lube oil header temperature high

Turbine electronic overspeed

Protective Status Starting device trouble

Inlet guide vane trouble

Manual trip

Control speed signal lost

Exhaust pressure high

Protective speed signal trouble

Control speed signal trouble

Breaker failure trip lockout

Vibration tripLoss of protection HP speed inputs

Customer trip

Control system fault

Low lube oil pressure

Fire indication

Generator lockout trip



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HMI

The HMI or user interface is provided through a GE CIMPLICITY

graphics

window with unit-specific screens, a Microsoft

Windows

operating system, and a

Control Systems Toolbox with editors for application software. It can be applied as:

Primary user interface for single or multiple units

Gateway for communication links to other controllers

Permanent or temporary maintenance station

Engineering workstation

All control and protection is resident in the Mark VI controller, which allows the

HMI to be a non-essential component. With the turbine running, it can be

reinitialized or replaced with no impact on the controller. The HMI communicateswith the processor in the controller through the UDH.

Gas turbine control screens show a diagram of the turbine with the primary controlparameters. The diagram is repeated on most of the screens to provide a visual image

of the turbines performance while changing screens.

Typical Gas Turbine Screens

ControlScreens

MonitorScreens Auxiliaries Tests

Startup Bearingtemperature

Flame Overspeedtest

Motors Exhausttemperature

Water wash

FSR control Generator RTDs Start checkGenerator/exciter Wheelspace

temperatureTrip diagram

Synchronizing Seismic vibration Timers

Buttons on the right side of

all screens produce sub-menus of category-specific

screens.

The main screen is the Startupscreen. Since the gas turbine control provides fully

automatic startup including all interfaces to auxiliary systems, all basic commandsand all primary control parameters and status conditions start from this screen.

For example, the Startcommand can be sent to the Mark VI whenReady to Startdisplays in the startup status field. A pop-up window displays above the Start-up

button for verification. Upon verification, the application software checks the startup

permissives and starts a sequence that displays Startingand Sequence in Progressmessages.

If startup permissives were not satisfied, the messageNot Ready to Startdisplays,

with a message in the alarm field that identifies the reason. Additionally, when the

Auxbutton is clicked and the Start Checkscreen is selected, it displays graphicalinformation for the Start Check/Ready to Startpermissives.

A message reminds you to

investigate the nature of thelatched trip prior to clicking

Master Reset.

Trip conditions that display in the alarm field and in the Trip Diagram are accessed

by clicking the Auxbutton and selecting the Trip Diagramscreen. A trip duringstartup causes the messageNot Ready to Start.



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v o o

Mark VI also allows you to change a numeric setpoint, such asMegawatts (MW)fora generator drive or Speed Reference (TNPREF)for a mechanical drive, by entering

a setpoint value rather than issuing continuous discrete raise/lower commands. The

Mark VI application compares the requested setpoint with acceptable limits and the

present output to determine a suitable ramp rate to the new target.

The Mark VI supports trending displays for comparing operating parameters. A

startup trend can be set with pre-assigned parameters, such as meanExhaust GasTemperature (EGT),speed, maximum vibration, Compressor Discharge Pressure

(CPD), andFuel Stroke Reference (FSR). More detailed information and trending are

provided on supporting screens, along with the capability to create customizedtrends.

Typical Turbine Instrumentation



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Typical Turbine InstrumentationAnalog and digital devices found on a typical dual fuel gas turbine without emission

suppression are provided in the following tables.

Analog Turbine Devices

Device Parameter Device Type

28FD Flame detector Flame scanner

39V-x Vibration sensor Velocity pickup

65FP Liquid fuel pump servo Torque motor

65GC Gas control valve servo Torque motor

65NZ Nozzle control servo (2-shaft only) Torque motor

77FD Liquid fuel flow Magnetic pickup

77NH High Pressure shaft speed Magnetic pickup

77NL Low Pressure shaft speed (2-shaft) Magnetic pickup

90SR Gas ratio valve servo Torque motor90TV Inlet guide vane servo Torque motor

96FG-2 Gas fuel control pressure Transducer

96GC Gas control valve LVDT

96NC Nozzle control (2-shaft only) LVDT

96SR Gas ratio valve LVDT

96TV Inlet guide vane LVDT

CTDA Compressor discharge temperature Thermocouple

CTIF Compressor inlet temperature Thermocouple

TTWS-x GT wheelspace temperature Thermocouple

TTXD-x GT exhaust temperature Thermocouple



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Digital Turbine Devices

Device Parameter Device Type

12HA Mechanical overspeed bolt sensor Limit switch

20FG Gas fuel trip oil Solenoid valve

20FL Liquid fuel trip oil Solenoid valve

26FD Liquid fuel temperature Temperature switch

26QA/T Lube oil temperature high alarm / trip Temperature switch

26QL/M Lube oil temperature low / moderate Temperature switch

26QN Lube oil temperature normal Temperature switch

33CS Starting clutch Limit switch

33FL Liquid fuel stop valve position Limit switch

33HR Ratchet position Limit switch

45F-x Fire detector Temperature switch

63AD Atomizing air differential pressure Pressure switch

63FD Liquid fuel pressure Pressure switch

63FG Gas fuel pressure Pressure switch

63HG Gas fuel trip oil pressure Pressure switch

63HL Liquid fuel trip oil pressure Pressure switch

63LF1 Liquid fuel filter pressure Pressure switch

63LF2 Liquid fuel forwarding filter pressure Pressure switch

63QA/T Lube oil header / bearing pressure Pressure switch

63QL Lube oil pressure Pressure switch

63TF Inlet filter pressure Pressure switch

71QH Lube tank high level Pressure switch

71QL Lube tank low level Level switch

71WL Water tank low level Level switch



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Packaging

Mark VI packages can be customized to meet any site requirement. Package options

that fit into the Mark I, Mark II and Mark IV footprints are shown below.

Component Description

Card Backplane VME type (VERSA module Eurocard)

Cabinet NEMA 1 convection cooled, similar to IP-20

Cable Entrance Top and/or bottom

Material Sheet steel

Terminal Blocks 24-point, barrier type terminal blocks that can be unplugged formaintenance. Each screw can terminate two #12 AWG (3.0mm

2), 300-volt insulated wires.

Width Depth Height Weight

36" (900 mm) 36" (900 mm) 91.5" (2,324 mm) 1300 lbs(590 Kg)

Dimensions- Cabinet Option #1

- Cabinet Option #2

54" (1350 mm) 36" (900 mm) 91.5" (2,324 mm) 1600 lbs(725 Kg)



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Typical Power Requirements

The control cabinet is powered from a 125 V dc battery bus that is normally short-

circuit protected in the motor control center. Both sides of the floating 125 V dc busare continuously monitored for grounding. A floating bus eliminates the need for the

dc ground relay and dc under-voltage relay present in older controllers. The 125 V dc

bus is fuse-isolated in the Mark VI power distribution module and sent to:

VME rack power supply for each control module

Termination boards for the field contact inputs and the turbine solenoids

A separateuninterruptible power

supply (UPS) is required

to power the HMI and

network equipment.

Additional 3.2 A fuse protection is provided on the termination board for each

solenoid. A 120 V ac feed is provided for ignition transformers. Control cabinetpower specifications are shown below.

Steady-state Voltage Frequency Load Comments

125 V dc (100 to 145 V dc) 10 A dc Ripple


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g GE Energy1502 Roanoke Blvd.Salem, VA 24153-6492 USA GEI-100538ARevised 051109Issued 020525

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GE MARK VI