Excitation_Amdt_4_Attachments.pdf

U.S. ARMY CORPS OF ENGINEERS

HARRY S. TRUMAN DAM

WARSAW, MISSOURI

EXCITER REPLACEMENT

LIMITED ASBESTOS

INSPECTION REPORT

of the

HYDRO EXCITATION SYSTEM

October 19, 2016

Prepared for:

US Army Corps of Engineers ® Kansas City District

Prepared by:

02 82 13.00 10 Attachment Amendment 0004

2200 W. 25th St. Lawrence, Kansas 66047 Main: 800.444.6382 Fax: 785.842.6993 www.metaenvironmental.net

TABLE OF CONTENTS

1.0 INTRODUCTION

2.0 SCOPE AND PURPOSE

3.0 ASBESTOS SURVEY REPORT

3.1 Homogeneous Areas

3.2 Sampling Strategy

3.3 Laboratory Analysis

4.0 FINDINGS

5.0 CONCLUSIONS

APPEDICIES

Appendix 1 Bulk Sample Log

Appendix 2 Analytical Results

Appendix 3 Photographs

HARRY S. TRUMAN DAM

LIMITED INSPECTION OF

ASBESTOS CONTAINING MATERIALS

1.0 INTRODUCTION

META Consulting LLC (META) has conducted a limited inspection for asbestos containing materials

(ACM) on the Hydro Excitation System at Harry S. Truman Dam, Warsaw, Missouri. The visual inspection and sampling was conducted on October 19, 2016 by Robert Baer, a Missouri licensed and EPA accredited

Asbestos Inspector.

2.0 SCOPE AND PURPOSE

META performed this survey to determine whether asbestos was present in the Hydro Excitation Systems

Electrical Cabinets in preparation for the removal and disposal of these cabinets as part of the Exciter

Replacement project. The inspection was conducted to determine the possible presence of asbestos and to ensure compliance with OSHA requirements and protocols.

2.1 Responsibilities

META’s responsibilities on this project were limited to performing the inspection and sample collection according to the agreed upon standards, personal protection for its employees, arranging for analysis at a qualified laboratory, and reporting the results. The client was responsible for providing safe access to all spaces to be inspected and for determining the scope of the project. Plant personnel ensured power to the area was locked-out to be able to safely access the interior and exterior of the cabinets during the inspection.

3.0 ASBESTOS SURVEY REPORT

3.1 Homogeneous Areas

Homogeneous Areas were identified by the accredited inspector. A Homogeneous Material or

Homogeneous Area (HA) is a material component in a building that is of the same color, texture, and date of application or construction. (ex. Same exact floor tile in different rooms in a building).

3.2 Sampling Strategy

The inspection sampling strategy was to conduct a visual inspection and then collect samples of all suspect asbestos containing materials located in or on any of the cabinets. After completing the visual inspection it was determined that sampling would not (or could not) be conducted because of the large number of suspect electrical components consisting of individual wire jacketing, wire insulations, connectors, mounting blocks, and non-conductive panels and shields that were located in the cabinets.

3.3 Laboratory Analysis

Bulk samples were analyzed by QuanTEM Laboratories, Oklahoma City, OK using Polarized Light

Microscopic analysis, EPA Method 600/M4-82-020 with dispersion staining techniques to determine the asbestos content of the bulk samples. Any material that contains greater than one (1) percent asbestos is considered an ACM and must be handled according to Occupational Safety and Health Administration

(OSHA), Environmental Protection Agency (EPA), and all applicable state and local regulations. Analytical results are located in Appendix 2.

4.0 FINDINGS

Asbestos Containing Material (ACM) was not identified during the limited sampling of dust and a cloth cable covering in the cabinets.

** A sample not related to the Hydro Excitation System was collected of the Transite wall panels located in the Electronics Shop. This material contained 25% Chrysotile asbestos.

The analytical results for all suspect materials sampled are located in Appendix 2.

5.0 CONCLUSION

Without extensive sampling of the numerous electrical components or contacting manufactures of the equipment for documentation that all the materials included in the cabinets are not ACM, the only other option is to assume the materials are indeed asbestos containing. Since the cabinets were still in service, and would be re-energized after the inspection, sampling of the electrical wiring and electrical components was not considered practical. Instead it was determined that the materials would be assumed to be asbestos containing, and removed and disposed as asbestos.

Each cabinet will be removed as an entire intact unit by unbolting it from the structure and slicing or shearing the cables connecting the cabinets to the power supply. An Asbestos Awareness Training class of approximately 2-hour will be required for anyone participating in the actual hands-on removal operations of the cabinets.

Personal air monitoring will be conducted during the cabinet removal operations to document employee exposures. The monitoring will last for approximately 8-hours, or for the removal of all the cabinets, which ever duration is less.

The monitoring along with documentation of the work practices will be used for the purpose of determining the worker exposure with the intent of establishing a Negative Exposure Assessment for this specific type of operation.

APPENDICES

APPENDIX 1

BULK SAMPLE LOG

APPENDIX 2

ANALYTICAL

RESULTS

Date Received: 10/24/2016

Project: ACM Sampling

QuanTEM Lab No. 271565

Analyzed By: Gayle Ooten

Methodology: EPA/600/R-93/116

Polarized Light Microscopy Asbestos Analysis Report

Project Location: Truman Dam, MO

Project Number: 101916ACM01

Account Number: B614

Received By: Peyton Awbrey

Date Analyzed: 10/30/2016

QuanTEM

Sample ID

Client

Sample ID Composition

Color /

Description Asbestos (%)

Non-Asbestos

Fiber (%)

Client: META Environmental

Bob Baer

2200 West 25th St.

Lawrence, KS 66047

Non Fibrous

001 01 Homogeneous Insect PartsAsbestos Not Present 50Cellulose

Debris

Brown

002 02 Homogeneous CaCO3

Insect Parts

Asbestos Not Present 40Cellulose

Debris

Brown

003 03 Homogeneous CaCO3

Insect Parts

Asbestos Not Present 40Cellulose

Debris

Brown

004 04 Homogeneous Asbestos Not Present 100Cellulose

Fabric

Black

005 05 Homogeneous Asbestos Not Present 100Cellulose

Fabric

Black

006 06 Homogeneous CaCO3

25Chrysotile

Asbestos Present NA

Transite

Gray

Date of Report

10/30/2016

Gayle Ooten, Analyst

QuanTEM is a NVLAP accredited PLM laboratory (Lab Code: 101959-0). This report relates only to the specific items tested. NVLAP accreditation applies only to analysis performed utilizing EPA/600/M4-82-020 and EPA/600/R-93/116 methods. This report may not be used to claim product endorsement by NVLAP or any agency of the US Government. This report may not be reproduced except in full, without the written approval of the laboratory.

Unless otherwise noted, upon receipt the condition of the sample was acceptable for analysis.

APPENDIX 3

PHOTOGRAPHS

Photo

#1:

View of one side of the Exciter Cabinets Photo

#2

View of electrical components in a cabinet that is suspect and was not sampled

#3:

View of area on floor in cabinet that had a dust sample collected that contained no asbestos.

Photo

#4:

View of electrical components in a cabinet that is suspect and was not sampled

#5:

Cloth Jacket/Covering from cabinet to door sampled and was not ACM.

Photo

#6:

View of vinyl and cloth covered cables that were not sampled.

SSN: XXX-XX-2561

P.O. Box 4693 - Lawrence, KS. 66047 - 800.444.6382 Expiration: 12/15/2016

Certificate # MEFFDBBF2BD4A845E

Robert J. Baer has on 12/15/2015, in Lawrence, KS completed the requirements for asbestos accreditation under Section 206 of TSCA Title II, 15

USC 2646

4-hr. Asbestos Building Inspector Refresher as approved by the US EPA under 40 CFR 763 (AHERA) from 12/15/2015 to 12/15/2015 and passed the associated exam on 12/15/2015 with a score of at least 70%

Instructor

Thomas Mayhew

Thomas Mayhew

President www.metaenvironmental.net

48 19 26.00 26 Attachment 1

HARRY S. TRUMAN POWER PLANT

DESIGN MEMORANDUM NO. 38

ANALYSIS OF DESIGN

SECTION V - ELECTRICAL DESIGN

CHAPTER NO. EI05

CONTROL AND COMMUNICATION SYSTEMS

EI05-LGENERAL. The Harry S. Truman Power Plant consists of six (6) hydro electric, slant-shaft synchronous generator/motors with six (6) reversible slant-type, adjustable-blade, pump/turbines. Operation as a generator is accomplished by conventional control methods. Selective and operational con trols for all modes of operation are located in a duplex type main control board in the control room. For motor operation, any 5 of the 6 generator/ motors can be started as a motor, apart from the system, using the back-to back synchronous start method. With the synchronous start method, any 2 of the 6 units are connected at standstill, field excitation is applied to both machines and then one of the units. is started as a generator. The second unit, as a motor, then comes up to the rated speed in synchronism with the starting unit and both units are automatically synchronized to the system.

After both units are synchronized to the system, automatic shutdown of the starting unit takes place and the starting unit is separated from the motor and system. The pump/turbine impeller blades are submerged at all times and no provision is made for condenser operation. Turbine blade pitch is automatically controlled by the governor.

EI05-2. ·UNIT·CONTROLS AND-EQUIPMENT.

EI05-2.1 GENERAL. Unit Controls are shown schematically on Plates 24 through 29.

The'control equipment consists of the following:

Duplex Main Control Board Duplex Recorder Board Duplex D.C. Switchboard Digital Central Processor Unit Auxiliary Relay Cabinet Battery Charging System UPS System for Digital Processor

Unit control logic is provided by a hardwired relay scheme with mUlticontact auxiliary relays and multicontact control switches. Indicating lights inform the operator how far the automatic sequence has progressed. The control scheme is fully automated in that by operating a start switch the unit will ready all auxilia~i~s. start itself, synchronize to the system and go to the load setting provided at the central processor.

El05-1

48 19 26.00 26 Attachment 2

E105-2.2 DUPLEX MAIN CONTROL BOARD consists of fourteen 28" front and rear control board panels with provisions for a future line panel at the right end of the board. The board utilizes conventional hardwired controls and instru ments on the front panels. Controls are logically grouped on a mimic bus.

Grouped window type annunciators are provided for unit, station, transformer and switchyard alarms. Individual breakdown of alarms on each window are provided by the central processor. The rear panels house all the unit, transformer, and line protective relays.

E105-2.3 DUPLEX RECORDER BOARD consists of six 24" front and rear recorder panels. The front recorder board panels house the following:

1) A 2 pen megawatt-megavar recorder for each unit.

2) A 2 pen megawatt-megavar recorder for line 1 and line 3 plus adequate space for mounting recorders for the two future line bays.

3) A set of recorder jack plugs for each unit with 2 transformer ja~ks on the unit 6 jack panel. All of these points are normally monitored by the digital processor for out-of-limits alarm conditions. The jack panel permits continuous monitoring of points via 2 sixteen point portable temperature recorders. The two recorders are equipped with cords and matching plugs for the jack panel. The jack panel monitors the output of the RTD signal conditioners furnished with the digital processor.

4) A head and tailwater level recorder with retransmitting slidewire' for use on the station net head assembly. The net head assembly is located on the same panel of the board and provides input to the unit governors.

5) A 2 pen station megawatt-megavar recorder for recording station load in or out. Total station load is computed by the central processor and provides an output signal to the recorder.

6) A water temperature recorder for measuring tailrace temperature from the powerhouse. The RTD for this instrument is located on the right bank at the gauge house below the powerhouse.

7) A high resolution frequency recorder for monitoring station fre quency between 59 and 61 hertz. Input is from a high resolution frequency transducer located on the same panel. The frequency transducer is equipped with high and low level limit switches that are independently adjustable.

When frequency deviates by ± .2 hz, all six load control switches on the front of the MCB are tripped to OFF.

8) Vibration Monitors for detecting abnormal unit shaft vibrations.

The rear recorder board panels house the following:

a. In and Out watthour meters for each unit and line with pulse initiating devices for input to the central processor. Space is provided for the two future sets of line In and Out Watthouse Meters.

E105-2

b. A station voltage recorder to provide a record of terminal voltage of any generator or line.

c. Two automatic synchronizers to provide speed and voltage matching pulses to the units and syncho-verifier outputs for switchyard breakers. On the same panels are all the speed and voltage matching auxiliary relays and the synchronizer ON-OFF control switches.

E.105-2.4 DUPLEXD~C~-SWITCHBOARD consists of six 24" front and rear switchboard panels. The front panels house the following:

1) Controls, instruments, and relays for the main station battery chargers.

2) Controls, instruments, and relays for the digital processor U.P.S.

system.

3) Essential A.C. distribution circuit breakers.

4) Instruments and relays for the station essential AC inverter.

The rear panels house all the 125VDC breakers for plant D.C. power. The D.C.

busses have guards to prevent accidental personnel contact.

E105-2.5 DIGITAL CENTRAL PROCESSOR provides the following functions:

1) Sequential events recording.

2) RTD analog monitoring and scanning for alarm conditions.

3) Equipment status monitoring.

4) Data logging for hourly, daily, and monthly operating logs.

5) MWh pulsercounting and totalizing Unit Load In or Out for Station Load recorder and telemetering to SPA.

6) Line MW totalizing for telemetering to SPA.

7) Unit Load Control.

8) Continuous monitoring of RTDs via portable recorders when so con nected. The central processor is housed in a six panel duplex board located in the control room. All peripheral equipment except the printers, portable recorders, and RTD jack panels are located in the duplex control board. The processor has a load center in the control board to feed all peripheral equipment. The load center is fed by a UPS system installed especially for the central processor. The processor continuously scans the unit. bearing, oil head, stator, and main power transformer temperatures as measured by local RTDs and signal conditioners. The load control equipment provides a

EI05-3

set point load control with setters at the operator console and the unit panel on the main control board. This system causes the generator to main tain base load for generating or pumping modes. The load control can also load and unload units at an adjustable MW per minute rate. The rate is settable from the operator's console. The portable recorders are for contin uously monitoring of any quantities that become questionable. The recorders are furnished with cords and plugs to match the jacks on the front of the recorder board.

E10S-2.6 UNIT AUXILIARY RELAY CABINET is provided to house the large number of relays required to provide automatic control of the station using relay control logic. This eliminates the need of using swinging panels on the main control board. The cabinet is conveniently located in the cable spread area immediately below the control room, adjacent to the 13.8kV switchgear.

Outline drawings showing equipment in the cabinet are found on Plate 6.

E10S-2.7 BATTERY CHARGING SYSTEM. Two static battery chargers are provided for maintaining the 12SVDC station battery. The two chargers' are interlocked so that only one can run at a time, providing backup should one fail. The chargers are located in a room for battery chargers adjacent to the station battery room. A 7.SkVA single phase essential A.C. inverter is connected to the battery and normally turned on but left unloaded to provide a hot standby A.C. source should the normal source fail. Schematics of chargers and inverter are shown on Plate S2.

E10S-2.8 uPS SYSTEM FOR DIGITAL PROCESSOR. A separate battery system, driven by a special static battery charger feeds a 10kVA inverter. If the A.C. power fails the inverter will continue to run from the battery. Battery voltage is 12SVDC. Battery capacity is adequate for one hour of operation with the normal source failed. The inverter is provided with a 120 volt panel for distribution. A single feeder feeds the digital processor load center. Schematic of equipment is shown on Plate S2 ••

E10S-3. AUTOMATIC CONTROL OF UNIT AS A GENERATOR. Refer to Plates 21 through 33 for schematics of unit controls.

~10S-3.1 GENERATOR STARTUP (unit 1 illustrated - others similar).

1) Operator makes following prestart checks:

a. Checks for off normal conditions on annunciator displays.

b. Ve.rifies that gate limit is at 0%.

c. Verifies control switch 43MA is in the "AUTO" position.

d. Verifies auto synchronizer switch 1A1 on the recorder board is ON.

e. Verifies that manual synchronizing switch 1GI is OFF.

E10S-4

f. Verifies that control switch lGP is in the "GEN" position.

g. Verifies that there are no clearances on the unit.

h. Desired load setting and loading rate entered on operator's console and load control turned on at operator's console.

1. Control switch lLC in "AUTO" position.

2) Operator then momentarily operates control switch lUG to the START position, initiating the automatic sequence.

3) The master relays (4-1, 4-2, and 4-3) pickup and seal-in.

Simultaneously the master unit stop relays pickup and seal-in (?-l, 5-2, 5-3, and 5-4). The 4 relays cause the following to occur:

-Unit cooling water valve opens (via 20WU) ~Inflatable gate seal deflates -Stub shaft oil cooler water solenoid valve (20SB) opens -Stab shaft packing box water solenoid valve (20SP) opens -Main shaft packing box water solenoid valve (20WS) opens -Main shaft oil cooler water solenoid valve (20SQ) opens -Generator lower journal bearing oil cooler water solenoid valve (20LG) opens -Generator thrust bearing oil cooler water solenoid valve (20TG) opens -Generator upper journal bearing oil cooler water solenoid valve (20UG) opens -Temperature scanning and recording functions activate -Generator heaters are disconnected (via 73GH) -The grease pump is turned on to start timers -Regulator startup relay 1 and LA pickup at excitation cubicle -Auxiliary relays 4X, 4Y, 4Z, 2U, and 4Xl pickup. RelaY'4X starts all five bearing high pressure pumps. Relay 4Y prevents high pressure pump startup from a creep signal after unit start is given. Relay 4Z starts all five bearing low pressure pumps. Relay 2U provides a time delay to r,elay 2UX. Relay 2UX starts the D. C. pumps after time delay 2U if the low pressure system has not developed sufficient pressure to open the control circuit pressure switch. Relay 4Xl picks up to prevent opera tion of the D.C. oil pump from a unit creep signal after the unit start signal has been given.

-Relay 74G2 picks up to operate fisherman's warning horn, pump-turbine pit horns, and generator/motor gallery horns.

-Mode relays 4G pick-up and seal in. Relay 4Gl positions l3.8kV break ers 52Gl, 52Pl, and 52PSl for generating and provides a contact to per mit synchronized closing of 52GM1. Relay 4G2 closes permissive contact in the incomplete sequence timer circuit (4Z), closes permissive con tacts in the 25Xl and 65MS circuits for generate mode synchronizing, and provides seal-in for the 5 relays so that generator stop can be initi ated by control switch lUG. Relay 4G3 provides a permissive contact for the 4XG circuit, provides the correct trip circuit during normal shut down for 52GM1, operates 65BA to position turbine blades to 8 degree

E105-5 blade pitch for generator startup, prepositions gate limit to the upper limit, and activates device 65SNL2 to permit gate opening beyond its set point of 65SNL2 (used in motor-start sequence). Relay 4G4 provides mode status to the digital processor, operates the GM relays at the excita tion cubicle, provides a synchronizing mode interlock in the 25Xl cir cuit, and prevents the 4P relays from picking up. Relay 4G-5 operates the 65PG relay at the governor to select the 3-D cam and net head controls for generate mode.

The 5 relays pick up and seal in simultaneous with the 4 relays. They cause the following actions to occur:

-Relay 5-1 causes breakers 52G1, 52P1, and 52PSl to preposition for generation as dictated by the 4G relays and provides seal in to the "stop" circuit.

-Relay 5-2 releases the gate limit lower circuit, closes permissive contacts in the 65SD and 25Xl circuits, opens a permissive contact in the 62 circuit and provides permissive operation of the 94 circuit (breaker 52GM1 trip free ckt).

-Relay 5-3 provides permissive contacts in gate lock circuit 65GL, mode permissive circuit 4XG, unit speed level raise circuit 65MS, and in speed no load circuit 65SNLlj and opens the normal trip circuit of breaker 52GMl.

-Relay 5-4 drops out regulator stop relays 5YA and 5YB at excitation cubicle, and operates with mode relays to start incomplete sequence timer 48.

4) Automatic sequencing proceeds from the above initializing events •.

Permissive relays 2Q, 3, and 4XG must have their conditions satisfied and pick up in sequential order for generator start to proceed.

-All unit bearing high pressure pumps must establish pressure and low pressure pumps must establish flow in order for relay 2Q to energize.

Flows and pressures must be maintained for the set time of 2Q in order for the sequence to proceed. After the delay, a 2Q contact closes in the 3 circuit.

-After 2Q circuit is satisfied, the 3 circuit must be satisfied. ~e following are conditions to be met:

No turbine shear pins failed (65SPF), inflatable gate seal down (63SP), brake air supply up (63ABSX), governor oil pressure up (63QG2), unit air cooler water flow established (8OWAl or 8OWAZ) and packing box and oil cooler water flow established for all the unit bearings. When these conditions are satisfied, the 3 relay will pick up and close a contact in the 4XG circuit.

-In order for 4XG to operate the unit, l3.8kV breakers 52G1,52Pl, and 52PSl must be properly positioned for generating, and the regulator positioned for startup. The A.C. regulator must position to ··Normal Synchronizing Voltage" and the D.C. regulator mus t position to '·Rated Voltage No Load." When these conditions are satisfied, relay 3CR and 6CR will operate and permit 4XG to operate.

E105-6

5) Operation of 4XG causes the brake air solenoid _(20AB) to bleed air pressure, operates the unit start sequence lights (Green "OFF", White "ON"), and closes a permissive contact in the gate lock control circuit (65GL).

6) When air brake pressure at the governor reaches 5 p.s.i., pressure switch 63AB will open to start timer 63ABY. After a delay long enough for all brake shoes to have released, the unit brake light will turn off and relay 63ABX will drop out. This will close the final contact in the gate lock circuit (65GL) and cause it to pick up. 65GL operates a limit switch when released and is the last contact to close in the 65SD circuit, thus picking up the shutdown solenoid.

7) The turbine runner blades are at fixed pitch (65BA circuit) and wicket gate travel is limited to about speed-no-Ioad by device 65SNL1.

Wicket gates open to maximum position and unit accelerates. As gates open, Unit Run Relays (95) operate and Unit dome light turns on, Generator symbol on main board turns on, C02 system is placed in service.

As unit reaches 95% speed, relays 13X and l3Y pick up and close exciter/ regulator breaker 41E and field breaker 41G. Transfer relays 83A, B, and C are picked up placing automatic A.C. regulator 90VA in service. When the machine terminal voltage reaches the setting of relay 27G, the 25Xl circuit will pick up and place the automatic synchronizer in service. Raise and lower pulses will be sent to the governor speed level motor 65MS via speed

EI05-7

matching auxiliary relays l5RX and l5LX. When terminal voltage is 95% (as determined by device 95VT at excitation cubicle), voltage matching pulses from the synchronizer are sent to device 90VM to match terminal voltage using the A.C. regulator. When speed and voltage are matched, the synchronizer closes its output contact to close synchronizing breaker 52GM1. For a unit in generate mode, relays 25Xl-l, 25Xl-2, and 25Xl-3 will pick up for auto matic synchronizing.

8) When 52GMl closes, the speed-no-load solenoid (65SNL1) is released, the incomplete sequence timer is stopped, the synchronizer is turned off, l3.8kV breaker close circuits for 52Gl, 52Pl, and 52PSl are opened, unit loss of field relay (40) is placed in service and governor relay 65DCO operates to permit the gains on the electronic governor circuits to go to the on-iine position (increases gains of proportional, integral and derivative modules to permit improved response).

9) The digital processor now automatically loads the ~nit by operating the speed level motor 65MS. When the unit wicket gates open to 50% the high pressure oil pumps shut down. The desired set point for load is entered at the main board load setter panel or at the plant control console. The unit loading rate is settable in megawatts per minute at the operator's console.

The guard and dead bands for the set load are also adjustable from the con sole. Once the unit reaches the desired load, the load setter can be turned off as the electronic governor will maintain the power output. If the load setting needs to be changed, the load control is turned on and the new load setting is entered at console or main control board. The unit will go to the new load setting.

10) To reactively load a unit (VARS), operate control switch 90VA on main control board to raise or lower until the desired reactive load is obtained. Then operate control switch 90ES on main control board the same direction until the null-balance meter on the main control board is centered.

E105-8

The need for this is because the regulator is actually d~signed with two regulators, an A.C. regulator to regulate the machine terminal voltage and a D.C. regulator to regulate the generator field voltage. Both regulators control the same bridge circuits, but only one can be in control at a time as determined by the 83 relays. Normal control is on the A.C. regulator. If the A.C. regulator fails, the 83 relays transfer and the D.C. regulator is in control. It is desirable to have both regulators set at the same point so that no disturbances will occur from a regulator transfer. When the null balance meter is centered, both regulators are set the same.

E105-3.2 GENERATOR RUNNING PROTECTION is provided by the following protec tive relay functions:

1) Generatordifferential87G provides fault protection of the unit within the zone provided on the current transformers. Any fault it sees will be tripped instantaneously via the 87GX lockout relay. In addition to trip ping the necessary breakers and device 5C, the C02 system releases C02 into the unit housing to extinguish any fire that might be present.

2) Generator Ground' Fault 64G provides backup to the·87G relay and also detects low level ground faults that 87G may not see or that are out of the 87G protective zone. The drawback to this scheme is that 64G sees the ground fault on all unit.s that are connected together and selective tripping is by an automated trial and error method. For units 1, 2, and 3: When 64G oper ates on a unit, first 87G is given a chance to clear the ground fault. If 87G does not operate after 4 seconds, breaker 52GM1 is tripped by 64GY1. If the ground fault is on unit 1, device 64G on the other units will clear, but 64G on unit 1 will remain operated and 4 seconds later .device 5C will operate for unit 1 and the ground fault is cleared from the system. The timers pro gress in 4 second increments to trip breakers and operate 5C only if the ground fault is on that unit. After a fault is cleared, any units tripped off can be resynchronized by manually operating their 52GM breaker control swit'ch to close. (64GY operates device 94 to lock out the automatic synchronizer. )

3) Overcurrent Relays51G operate on 120% unit current. These devices only annunciate and do not trip any breakers. The first reason for this is that it would only aggravate the operator if unit is running close to the trip level. The second reason is that during a fault, the unit impedance changes and the relay would not be able to operate at the overcurrent setting anyway.

4) Voltage'Controlled u OvercurrentRelay51V operates the overcurrent device at 67% unit current so that it can function during a fault. The breaker tripping contact is prevented from operating unless the voltage drops also, hence the voltage controls the output of the overcurrent device. The time dial is set on 51V so that it acts as a system backup relay to clear the generator if an external fault does not clear.

E105-9

5) Overvoltage Relay 59 operates at l8kV unit terminal voltage to protect the unit from overvoltage during load rejection by operating 5C and hence 4lE and 4lG thereby discharging the field.

6) Negative-Sequence 46G functions to prevent rotor heating during external faults. It will operate if a phase reversal occurs such as during a power swing or a fault that ~oesn't clear. 46G trips 5C when operated.

7) Phase -Balahce- Relay 46 functions to prevent unbalanced loading on the generator. If the imbalance exceeds its setting, it closes its output contact to trip device 5C.

8) Loss- of-Field AO detects loss of field by vars flowing into the unit. Relay 40 is not put into service until breaker 52GM is closed to prevent improper operation. 5C is operated when device 40 operates.

9) Stator Overtemperature Relay49G functions from 2 RTDs embedded in the generator stator windings. If the temperature exceeds the set limit,_ the 5M lockout relay shuts the unit down. 49GX prevents the unit from being re started until the unit has cooled back to limits of relay 49G. These limits may be restored quite rapidly as relay 49G functions not only from RTD tem perature but also unit current. Restart should be judged from temperature data rather than the relay resetting.

10) Excitation transformer unbalance 46ETX and overcurrent 5lETC detect the stated conditions and operate relay 5C.

El05-3.3 AUTOMATIC SHUTDOWN OF UNIT BY RELAY ACTION. Four types of shutdown can occur:

1) Operation of speed-no-load solenoid 65SNLl,

2) Mechanical shutdown 5M,

3) Complete shutdown 5C,

4) Regulator transfer.

-65SNLl is actuated by 115% unit speed or by transformer overtempera ture. When transformer temperature drops, 65SNLl will release and generator will return to its previous setting. Overspeed means that the unit will have to resynchronize and therefore 65SNLl will release when breaker 52GMl closes again. If unit speed does not reach load reject setting, unit will resynchronize automatically.

-5M is actuated by unit bearing overtemperatures, loss of critical flows and pressures, generator overtemperature and unit incomplete sequence.

Incomplete sequence is when the unit does not start and synchronize within the normal time span. The 5M relay is a lockout device that must be reset manually at the main board after the problem has been resolved

El05-l0 and the protective device reset. When the 5M relay operates, the 5 relays drop out and the shutdown solenoid 65SD is dropped out. This causes the wicket gates to close. At speed-no-load setting the unit breaker 52GM trips so as to avoid overspeed on a possible failed bearing.

-5C is actuated by emergency shutdown, low governor oil pressure, transformer lockout and unit protective devices that indicate possible faults on the generator. The 5C relay functions the same as the 5M relay except that the unit breaker 52GM1 is tripped immediately and overspeed will occur. 5C also immediately trips the exciter/regulator and field breakers.

-Regulator transfer: If the unit develops a field overcurrent (Maximum excitation limit) the regulator JK relays will function as follows:

a. First the A.C. regulator is given 30 seconds to correct the problem.

b. If not corrected, J2KX operates and JK3TD-starts a 10 second time cycle. J2KX functions to return 90EM to RVNL position if not there and annunciates.

c. J3KTD times out to then transfer to D.C. regulator control. If regulator still does not come down, operator should operate emergency shutdown.

E105-3.4 NORMAL GENERATOR SHUTDOWN. To remove a unit from service, the operator unloads the unit either by manual operation of the speed level control switch 1MS or by use of the load setter by setting for zero megawatts and turning on the load control. The vars are removed from the unit by operating control switch 90VA and following with control switch 90ES to maintain the null on the balance meter. The load control is turned off and the operator operates control switch lUG to "STOP." Automatic sequencing takes place as follows:

1) When wicket gates are at less than 50% gate, all high pressure oil pumps are turned on.

2) 5 relays drop out.

3) 65SNL1 circuit is opened causing the gates to rapidly close to the SNL position.

4) A.C. regulator positions to "Normal Synchronizing Voltage" and D.C.

regulator positions to "Rated Voltage-No Load" if not already there by the above. manual unloading actions.

5) When the gates are lowered to the speed-no-load point, breaker 52GM1 trips which in turn trips breakers 41G and 41E in order. Exciter/regulator tripping causes 90VM and 90EM to position to the full lower position.

6) The unit exciter/regulator is now off and the generator separated from the system and the shutdown solenoid drops out causing the wicket gates to close.

E105-11

7) With the water supply off, the unit coasts downs. At 30% speed the air brakes (20AB) are applied continuously and device 65BA is operated to increase blade pitch to 8 degrees to aid in slowing the unit. The unit run relays change to the unit stop condition and cause the following to occur:

-gate limit is lowered to the lower limit.

-dome light and main board generator symbol turn off.

-timer 62 starts.

-C02 system is deactivated.

-gate limit lowers to zero.

8) When device 62 times out, the 4 relays drop out and the unit auxili aries, recorders, temperature scans, etc., cease to function for the unit until the unit is restarted.

E105~4. AUTOMATIC CONTROL OF A UNIT AS A GENERATOR TO START A PUMP.

Operator selects one unit as a starting generator and one unit as a pump.

Refer to E105-5 for startup of unit as a pump. Unit 1 is selected for illustration as the starting unit.

1) Operator makes following prestart checks:

a. Checks for off normal conditions on annunciator displays.

b. Verifies that gate limit is a 0%.

c. Verifies control switch 43MA is in the "AUTO" position.

d. Verifies auto synchronizer switches lAl and lA2 on the recorder board are "ON."

e. Verifies that manual synchronizing switch lGl is "OFF."

f. Verifies that control switch lGP is in the "START PUMP" position.

g. Verifies that there are no clearances on the unit.

2) Operator then momentarily operates control switch lUG to the "START" position, initiating the automatic-sequence (the operator then operates control switch lUP of the unit to be started as a pump to the start

___ position) •

3) The master relays (4-1, 4-2 and 4-3) pick up and seal-in.

Simultaneously the master unit stop relays and the start pump mode relays ~ick up and seal-in (5-1, 5-2, 5-3, 5-4 and 4GP-l thru 4GP-7). The 4 relays cau~~_!he following to occur:

E105-l2

-Unit cooling water valve opens (via20WU) -Inflatable gate seal deflates -Stub shaft oil cooler water solenoid valve (20SB) opens -Stub shaft packing box water solenoid valve (20SP) opens -Main shaft packing box water solenoid valve (20WS) opens -Main shaft oil cooler water solenoid valve (2OWSQ) opens -Generator lower journal bearing oil cooler water solenoid valve (20LG) opens -Generator thrust bearing oil cooler water solenoid valve (20TG) opens -Generator upper journal bearing oil cooler water solenoid valve (20UG) opens -Temperature scanning and recording functions activate -Generator heaters are disconnected (via 73GH) -The grease pump is turned on to start timers -Regulator startup relay 1 and lA pickup at excitation cubicle -Auxiliary relays 4X, 4Y, 4Z, 2U and 4Xl pick up. Relay 4X in conjunc-tion with relay 4GP-7 starts all five bearing high pressure pumps.

Relay 4Y prevents high pressure pump startup from a creep signal after unit start is given. Relay 4Z starts all five bearing low pressure pumps. Relay 2U provides a time delay to relay 2UX. Relay 2UX starts the D.C. pumps after time delay 2U if the low pressure'system has not developed sufficient pressure to open the control circuit pressure switch. Relay 4Xl picks up to prevent operation of the D.C. oil pumps from a unit creep signal after the unit start signal has been given.

-Relay 74G2 picks up to operate fishermans warning horn, pump turbine pit horns and generator/motor gallery horns.

-Mode relays 4G and 4GP pick up and seal in. Relay 4Gl positions l3.SkV breakers 52Gl, 52Pl and 52PSl for starting a pump except as modified by relay 4GP5. Relay 4G2 closes permissive contacts in the 25Xl and 65MS circuits for synchronizing the pump mode unit. Relay 4G3 provides the correct trip circuit during normal shutdown for 52GMl.

Relay 4G-4 provides mode status to the digital processor, operates the GM relays at the excitation cubicle, provides a synchronizing mode interlock in the 25Xl circuit, and prevents the 4P relays from picking

up. Relay 4G-5 operates the 65PG relay at the governor to select the 3-D cam and net head controls for generate mode.

-Relay 4GP-l permits the pump mode incomplete sequence timer to operate in the starting units 5M circuit, selects the proper shutdown circuit in the 5 circuit, and locks the incomplete sequence timer off (pump mode unit times for incomplete sequence). Relay 4GP-2 de-energizes device 65BA to increase blade pitch on turbine to 8 degrees, selects device 65SNL3 to operate when unit reaches 85% speed so additional gate limit can be provided for final acceleration of unit (this circuit may not be needed), de-energizes 65SNL2 to limit gate opening to that required to give optimum starting torque for the unit (as determined by turbine model data), energizes 65SNLl to permit gate opening beyond that used during normal generator startup, selects gate limit motor setting 65MLB instead of 65MLC used for normal generation (should be a lesser set ting). Relay 4GP-3 prevents digital processor load control from func tioning on unit, selects the 4XGP circuit for operation and blocks the

El05-13

4XG circuit from operating. The 4GP-4X and 5GP relays function to allow cooldown time in the starting generator before it can be used again to start another pump (this is accomplished by holding the 5 circuit open for a set time delay on unit shutdown). Relay 4GP-5 functions to preset 13.8kV breakers 52Gl, 52Pl and 52PSI to the proper position for starting a pump (works with relay 4Gl), selects the pump start mode relays PSMI and PSM2 and locks out generate mode relays GMI and GM2 at exciter/ regulator. Relay 4GP-6 opens the 65PG circuit to prevent generate mode cam control although device 65BA prevents this by holding the turbine blades at fixed setting. 46P-6 also provides mode permissive contacts in the 33XX and 52TXX circuits and provides a bypass in the 25X circuit so that a generator can start a pump on the same generator bus. Relay 4GP-7 functions to prevent picking up relay 65PG (blades are not'on 3-D cam control at all for this mode of operation due to device 65BA) pre sets the circuit for releasing the brakes on the pump mode unit, and presets the circuit for tripping the pump start breaker 52PSI and breaker 52PS for the pump mode unit. Relay 4GP-7 functions to prevent high pressure oil pumps from stopping during the pump-start sequence (pumps normally shutdown at 50% gate and above).

The 5 relays pick up and seal-in simultaneously with the 4 relays. They cause the following actions to occur:

-Relay 5-1 causes breakers 52Gl, 52Pl and S2PSI to preposition for start ing a pump as dictated by 4G and 4GP relays and provides seal-in to "stop" ,circuit -Relay 5-2 releases gate limit lower circuit, closes permissive contacts in 65SD and 2SXl circuits and opens permissive contact in 62 circuit.

The 94 circuit, 52GMI trip free relay cannot be put into service since breaker S2GMI is held in tripped position by a contact from switch "lGP ...

-Relay 5-3 provides permissive contacts in gate lock circuit 6SGL, mode permissive circuit 4XGP, unit speed level raise circuit and in the 65SNLI circuit.

-Relay 5-4 drops out regulator stop relays 5YA and 5YB.at excitation cubicle.

The start pump mode is similar to generate mode and varies only as modified by the 4GP relays and control switch IGP.

4) Automatic sequencing proceeds from the above initializing events~ Permissive relays 2Q, 3 and 4XGP must have their conditions satisfied and pick up in sequential order to pump start to proceed.

-All unit bearing high pressure pumps must establish pressure and low pressure pumps must establish flow in order for relay 2Q to energize.

Flows and pressures must be maintained for the set time of 2Q in order for the sequence to proceed. After the delay, a 2Q contact closes in the 3 circuit.

EIOS-14

-After 2Q circuit is satisfied, the 3 circuit must be satisfied. The following are conditions to be met: no turbine shear pins failed (65SPF), inflatable gate seal down (63SP), brake air supply up (63ABSX), governor oil pressure up (63QG2), unit air cooler water flow established (8OWAl or 8OWA2) and packing box and oil cooler water flow established for all the unit bearings. When these conditions are satisfied, the 3 relay will pick up and close a contact in the 4XGP circuit.

-In order for 4XGP to operate the unit 13.8kV breakers 52Gl, 52Pl and 52PSI must be properly positioned for starting a pump and the regulator positioned for startup. The A.C. and D.C. regulators try to position to the full lower position if not already there via "PSB" and "PSBY" relay contacts in the 90VM and 90EM circuits. The lower circuit is also interrupted when breakers 41E and 41G are both closed via relay lCRA.

Breakers 41G and 41E are closed immediately on start signal. Regulator selector relay 83 is not picked up, therefore the D. C. regulator is in control. 90VM and 90EM position themselves to NSV and RVNL and then close checkback contact 6CR in the 4XGP circuit. Note that the A.C.

regulator is not put in service on the unit in this mode. Also, the D.C. regulator is positioned and checked, but control of the regulator is by the local manual device 90EFA instead of by 90EM. If the setting on 90EFA is changed from the required setting a limit switch will open and prevent 4XGP from picking up. When field flux is established on the unit, device 2FD will close a permissive contact in the 4XGP circuit.

The last condition for ,picking up 4XGP is that the pump mode unit being started must have its 4XP circuit picked up which in turn picks up common relay 4XXX after a short stabilizing delay. With all conditions met, relay 4XGP picks up and seals in.

5) 4XGP causes the following actions to occur:

-The unit start sequence lights on the main board change from green "on" to white "on."

-A permissive contact closes in the starting unit gate lock circuit

65GL.

-Device 20AB is de-energi,zed to release the brakes on the starting unit.

(Note: this is not an instantaneous process.)

-Common auxiliary devices 25Z-SB and 33XX are energized. 33XX releases the brakes on the pump mode unit and 2SZ-SB sets up the synchronizing busses for synchronizing any pump with any generator.

6) When air brake pressure at the governor reaches 5 p.s.i., pressure switch 63AB will open 'to start timer 63ABY. After a delay long enough for all brake shoes to have released, the unit brake light will turn off and relay 63ABX will drop out. This will close the final contact in the gate lock circuit (65GL) and cause it to pick up. 65GL operates a limit switch when released and closes a permissive contact in the 65SD circuit. When air brake pressure at the pump mode unit governor drops to 5 p.s.i., its pressure switch 63AB will open to start its timer 63ABY. When the time delay is over it will operate its 63ABX relay which in turn picks up common auxiliary relay 63BXX. This will be the final contact to close in the 6SSD circuit thus picking up the shutdown solenoid.

EI05-15

7) The turbine runner blades are at fixed pitch (65BA circuit) and wicket gate travel is limited to the position that device 65SNL2 will permit which is an optimum torque position. The wicket gates open to this setting and the unit begins to accelerate, driving the pump mode unit in direct.

synchronism with it. As the gates open the unit run relays (95) operate and· unit dome light turns on, generator symbol on main board turns on and C02 system is placed in service. When the two units reach 85% speed, device 65SNL3 is energized to provide additional gate limit so that synchronous speed can be reached. As unit reaches 95% spoeed, relays 13X and 13Y pick up to close a permissive contact in the 25X circuit. When terminal voltage on the machine reaches 95% of normal, relay 27GX will close a contact in'the 25X circuit. Note that only relays 25X1-1 and 25Xl-2 pick up for a unit starting a pump. Voltage will occur at the same time on the pump mode unit and its 25X circuit will also pick up, but only the 25X-3 and 25X-P relays will pick up on the pump mode unit. The 25Xl-2 relay is the one that turns on the automatic synchronizer and the synchronizer used will always be the one on the bus of the starting generator (in this case starting generator is unit #1, therefore synchronizer is the one for main generator bus #1). Speed matching pulses will be sent via devices 15RX and 15LX to the starting unit speed level motor 65MS to match unit speed to the power system. Voltage matching is accomplished with the pump mode unit voltage regulator. When speed and voltage are matched, breaker 52GM on the pump mode unit closes.

The pump is now on line but is drawing all its power from the starting unit.

8) Closing the 52GM breaker is the beginning step in shutdown of the starting generator. The folloWing sequence automatically occurs: .

-Common auxiliary relay 52GMXX picks up to prevent 52PS breakers from tripping on starting bus differential. These breakers are not capable of interrupting a system fault and therefore only the 52GM breaker may be used. The same condition is also true for a starti~g generator differential or other protective relay actions that would normally trip the 52PS breakers.

-Common auxiliary relays 52XX1 and 52XX2 pick up. This causes a permissive con~act to close in the 52TXX circuit to prepare the 52PS breakers for tripping. The 5XX, 5RXX circuit is also energized and the 20GMLX circuit is energized via relay 5RXX to establish a slow closure rate. 52XX2 turns off the automatic synchronizer by dropping out the 25X circuit on the starting generator. After the 5XX time delay, relay 5XX1 operates to drop out the 5 circuit on the starting generator. The 5 relays open the speed-no-load circuit 65SNLI and also drops out the shutdown solenoid 65SD (Note: breaker 52GM1 was never closed, therefore the 52GMlbx contact is open). The gates close at the rate prOVided by device 20GML. As the gates pass thru speed-no-load a gate position switch 33SNL-4 closes to operate common auxiliary relay 52TXX and trip the two 52PS breakers that are closed. When breaker

E105-16

52PS1 trips, the rate limiter 20GML returns to normal and gates close at normal rate. The 5 relays also close a contact in the 62 circuit, drop out the 4XGP relay, open the 65MS raise circuit, open the 25X circuit to prevent resynchronizing attempts, picks up the 5GP circuit, and provide~ a stop signal to the regulator. When the gates close completely, contact 33-0-4 opens to start timer 5GP. Unit cannot be restarted until 5GP times out and recloses its contact in the 5 cir cuit. This is to allow for cooldown of the unit after a "start ptunp" operation. The regulator stop signal picks up relays 5YA and 5YB. The A.C. and D.C. regulators have not been adjusted and should therefore still be at the prepositioned settings of NSV and RVNL. As 52PS1 trips the exciter/regulator breakers 41E and 41G also trip. The A.C. and D.C. regulator then preposition to the full lower position~

9) With the water supply off the unit coasts down and at 30% speed, the brakes are applied, (Note: 65BA held the blades fixed through the pump start process) and the unit will come to rest. Note also that the high pressure oil pumps never stopped during ptunp start. As the brakes are applied, the unit. run relays 95 return to the unit stop position turning off the unit dome light, main board unit symbol and the unit C02 system, starts timer 62 and gate limit is lowered to 0%. When 62 times out, the 4 relays drop out and the unit auxiliaries, recorders, temperature scans, etc. cease to function for the unit until the unit is restarted. This automatic , sequence can be stopped manually at any time by operating lUG on unit 1 and lUP on the pump mode unit to "STOP."

E105-S .AUTOMATIC·CONTROL OF UNIT AS·A PUMP.

E105-5.1 STARTING PUMP. Operator selects one unit as a starting generator and one unit as a pump. Refer to E105-4 for startup of unit as starting generator. Unit 4 is selected here for illustration as the pump unit in conjunction with unit 1 as the starting unit.

1) Operator makes the following prestart checks:

a. Checks for off normal conditions on annunciator displays.

b. Verifies that gate limit is at 0%.

c. Verifies control switch 43MA is in the "AUTO" position.

d. Verifies auto synchronizer switches 1A1 and 1A2 on the recorder 1,.oard are "ON."

e. Verifies that manual synchronizing switch IG1 is "OFF."

f.