2022 Design and Construction Standards - Section 6 Generator Set

10 SECTION 6 – STANDBY POWER GENERATION SYSTEMS PART 1 - GENERAL 11 Description of Work It is the intent of this specification to describe an emergency standby power generator system that has been prototype tested , factory built , production tested , site tested , of the latest commercial design , together with all accessories necessary for a complete installation for all wastewater pumping stations and well community pumping systems The equipment supplied and installed shall meet the requirements of the National Electrical Code and all applicable local codes and regulations All equipment shall be new , of current production by a national firm which manufacturer the generator , controls , and assembles the generator set as a matched unit so that there is one source responsibility for warranty , parts , and service through a local representative with factory - trained service personnel The firm shall have a minimum of 10 years experience in manufacturing systems of the type specified herein 12 Submittal Submittal shall include specification sheets showing all standard and optional accessories to be supplied , schematic wiring diagrams , dimension drawings , and interconnection diagrams identifying by terminal number each required interconnection between the generator set and other remote devices if included elsewhere in these specifications Generator sizing calculations as well as fuel tank sizing calculations shall be included in submittal Equipment manufacturers shall furnish six 2 copies of an operating and service manual covering their equipment The manual shall contain complete descriptions of each item of equipment and a complete parts list showing factory parts numbers It shall also contain complete operating and service instructions and shall be tabbed and indexed for easy use Manuals shall be submitted within 60 days after final approval of shop drawings Parts and certified service technicians local 150 miles and statement of 10 - year manufacturing experience List of establishments providing certified part including contact addresses , websites , and telephone numbers , and spare parts item numbers 13 Testing To assure that the equipment has been designed and built to the highest reliability and quality standards , the manufacturer shall be responsible for design prototype tests as described herein Components of the emergency system , such as the engine generator set , transfer switch , and accessories shall not be subjected to prototype tests since the tests are potentially damaging Rather , similar design prototypes , which will not be sold , shall be used for these tests Prototype test programs shall include the requirements of NFPA - 110 and the following 1 Maximum power kw 2 Maximum starting kva at 35 instantaneous voltage dip 3 Alternator temperature rise by embedded thermocouple and by resistance STANDBY POWER GENERATION SYSTEMS SECTION 6 - 1 2022 RevisionPageSECTION 6 – STANDBY POWER GENERATION SYSTEMS method per NEMA MG1 - 2240 and 1640 4 Governor speed regulation under steady - state and transient conditions 5 Voltage regulation and generator transient response 6 Fuel consumption at ¼ , ½ , ¾ , and full load 7 Harmonic analysis , voltage waveform deviation , and telephone influence factor 8 Three - phase line - to - line short circuit test 9 Cooling airflow 10 Torsional analysis testing to verify that the generator set is free of harmful torsional stresses 11 Endurance testing 14 Warranty The emergency generator system shall be warranted by the manufacturer for one year or 2,000 hours , whichever occurs first , from the date of the site start - up PART 2 - PRODUCTS 21 The standby generator set shall be rated standby power defined as continuous operation for the duration of any power outage volts , 3 phase , 4 wire , 08 power factor , kw , kva , amperes at feet altitude , and ° Fahrenheit The generator shall be capable of starting and running all pumps installed at the station 22 Final Production Tests Each generator set shall be tested under varying loads with guards and exhaust system in place The tests shall include the following 1 Single - step load pickup 2 Transient and steady - state governing 3 Safety shutdown device testing 4 Voltage regulation 5 Rated power 6 Maximum power Upon request , arrangements to witness this test will be made or a certified test record will be sent prior to shipment 23 Engine The cubic inch displacement engine shall deliver a minimum of hp at a governed speed not to exceed 1,800 rpm The engine shall be equipped with the following 1 Engine driven or electric fuel transfer pump , fuel filters and electric fuel shut - off valve STANDBY POWER GENERATION SYSTEMS SECTION 6 - 2 2022 RevisionPageSECTION 6 – STANDBY POWER GENERATION SYSTEMS 2 Gear driven governor capable of regulating the no load to full load frequency to a 5 maximum and capable of 033 Steady State frequency regulation 3 12 - volt positive engagement solenoid shift - starting motor 4 Battery charging alternator with solid - state voltage regulation 5 Positive displacement , full pressure lubrication oil pump , cartridge oil filters , dipstick , and oil drain 6 Dry - type replacement air cleaner elements 7 NOTE Engines requiring glow plugs will not be acceptable when NFPA - 99 or NFPA - 110 Type 10 ten - second transfer requirement must be met The naturally aspirated or turbo charged engine shall be fueled with No 2 diesel , and shall be liquid cooled A unit - mounted radiator , blower fan , water pump , thermostat , and radiator duct flange unhoused only shall properly cool the engine with up to 05 inches H 0 external static pressure on the cooling system 2 24 Generator The alternator shall be salient - pole , reconnectable , 12 - lead , self ventilated , of drip - proof construction with amortisseur rotor windings and skewed for smooth voltage waveform The insulation material shall meet the NEMA standard MGI - 2240 and 1640 for Class H and be vacuum impregnated with epoxy varnish to be fungus resistant per MIL I - 24092 or be multiply dipped and baked with nonhygroscopic varnish with a final dip of epoxy The excitation system shall be brushless construction controlled by a solid - state voltage regulator with adjustable volts - per - Hertz operation capable of maintaining voltage within ± 2 at any constant load from 0 to 100 of rating The regulator must be sealed from the environment and isolated from the load to prevent tracking when connected to SCR loads On application of any load up to the rated load , the instantaneous voltage dip shall not exceed 20 and shall recover to ± 2 of rated voltage within one second The generator shall be capable of sustaining at least 250 of rated current for at least 10 seconds under a 3 - phase symmetrical short by inherent design or by the addition of an optional current boost system The generator shall be capable of accepting the loads that were specified with kva , kw being the largest running loads and 15 being the largest instantaneous voltage dip when loads are started as specified on the loads report A resettable line current sensing circuit breaker with inverse time versus current response shall be furnished and shall not automatically reset preventing restoration of voltage if maintenance is being performed This breaker shall protect the generator from damage due to its own high current capability and shall not trip within the 10 STANDBY POWER GENERATION SYSTEMS SECTION 6 - 3 2022 RevisionPageSECTION 6 – STANDBY POWER GENERATION SYSTEMS seconds specified above to allow selective tripping of downstream fuses or circuit breaker under a fault condition The generator , having a single maintenance free bearing , shall be directly connected to the flywheel housing with a semiflexible coupling between the rotor and the flywheel 25 Controller Set - mounted controller capable of facing right , left , or rear shall be vibration isolated on the generator enclosure The microprocessor control board shall be moisture proof and capable of operation from - 40C to 85C Relays will only be acceptable in high current circuits Circuitry shall be of plug - in design for quick replacement Controller shall be equipped to accept a plug - in device capable of allowing maintenance personnel to test controller performance without operating the engine The controller shall include the following 1 Fused DC circuits 2 Complete two - wire start stop control , which shall operate on closure of a remote contact 3 Speed sensing and a second independent starter motor disengagement system shall protect against the starter engaging with a moving flywheel Battery charging alternator voltage will not be acceptable for this purpose 4 The starting system shall be designed for restarting in the event of a false engine start , by permitting the engine to completely stop and then reengage the starter 5 Cranking cycler with 15 - second ON and OFF cranking periods 6 Over crank protection designed to open the cranking circuit after 75 seconds if the engine fails to start 7 Circuitry to shut down the engine when signal for high coolant temperature , low oil pressure , or over - speed is received 8 Engine cool down timer factory set at five minutes to permit unloaded running of the standby set after transfer of the load to normal 9 Three - position AUTOMATIC - OFF - TEST selector switch In the test position , the engine shall start and run regardless of the position of the remote starting contacts In the automatic position , the engine shall start when contacts in the remote - control circuit close and stop five minutes after those contacts open In the off position , the engine shall not start even through the remote start contacts close This position shall also provide for immediate shutdown in case of an emergency Reset of any fault lamp shall also be accomplished by putting the switch to the off position 10 Indicating lights to signal 1 Not - in - auto flashing red 2 Over - crank red 3 Emergency Stop red STANDBY POWER GENERATION SYSTEMS SECTION 6 - 4 2022 RevisionPagePage pageNumber5SECTION 6 – STANDBY POWER GENERATION SYSTEMS 4 High engine temperature low coolant level red 5 Over - speed red 6 Low Oil Pressure red 7 Battery charger malfunction red 8 Low battery voltage red 9 Low fuel red 10 System ready green 11 Pre - alarm high engine temperature yellow - liquid cooled models 12 Pre - alarm low oil pressure yellow 13 Low coolant temperature red - liquid cooled models Required to meet NFPA - 99 or NFPA - 110 Level 1 regulations 11 Test button for indicating lights 12 Alarm horn with silencer switch per NFPA - 110 13 Terminals shall be provided for each signal in 10 above for connection to remote monitoring devices 26 Instrument Panel A set instrument panel shall include the following 1 Dual range voltmeter , 3 ½ , ± 2 accuracy 2 Dual range ammeter , 3 ½ , ± 2 accuracy 3 Voltmeter - ammeter phase selector switch 4 Lights to indicate high or low scale 5 Direct reading pointer - type frequency meter , 3 ½ , ± 5 accuracy , 45 to 65 Hertz scale 6 Panel illuminating lights 7 Battery charging meter 8 Coolant temperature gauge liquid cooled models 9 Oil pressure gauge 10 Running time meter 11 Voltage adjust rheostat ± 5 range 27 Accessories The following accessories shall be provided 1 Over voltage protection will shut down the unit after one second of 15 more over voltage 2 Battery rack , battery cables , 12 - volt battery ies capable of delivering the minimum cold - cranking amps required at 0 ° Fahrenheit per SAE Standard J - 537 3 Gasproof , seamless , stainless steel , flexible exhaust connector s ending in pipe thread or SAE flange 4 Flexible fuel lines rated 300 ° F and 100 PSI ending in pipe threads 5 Engine exhaust silencer , coated to be temperature and rust resistant , rated STANDBY POWER GENERATION SYSTEMS SECTION 6 - 5 2022 RevisionPagePage pageNumber6SECTION 6 – STANDBY POWER GENERATION SYSTEMS for critical applications Exhaust noise shall be limited to 85 dba as measured at 10 feet in a free - field environment 6 Block heater of proper wattage and voltage , thermostatically controlled to maintain engine coolant at 90 ° F 32 ° C to meet the start up requirements of NFPA - 99 or NFPA - 110 regulations 7 Trickle type battery charger with an adjustable low charge rate of 50 to 300 mili - amperes and a manual , high charge rate of 2 amperes 8 Steel weather - protective enclosure with removable or hinged side panels to allow inspection and maintenance The enclosure shall be coated with ASA gray primer and two coats of high - gloss , weatherproof , sag resistant vinylac in the manufacturer’s standard color through an electrical bonding process The specific exhaust silencer shall be vibra - mounted on the roof of the enclosure 9 Vibration isolators shall be provided between the engine - generator and welded steel base 10 A - gallon sub - base mounted double wall steel fuel tank with level gauge and low - level alarm contract Note fuel tank volume shall be sufficient for operation under full load for 48 hours 11 Four 4 sets of keys shall be provided to the County 28 Automatic Transfer Switch 1 Except as otherwise indicated , provide manufacturer’s standard design , materials and components as indicated by published project information , designed and constructed as recommended by manufacturer for duty indicated , and as required for a complete installation 2 Transfer switch shall be capable of switching all classes of load and for continuous duty at the rated current with switch mounted in the enclosure 3 The transfer switch shall be double throw , actuated by two electrical operators momentarily energized and connected to the transfer mechanism by a simple over - center linkage with a transfer time of 3 seconds The time delay of 3 seconds between the opening of the closed contacts and the closing of the open contacts is to allow the loads to be demagnetized before transfer The transfer switch shall be capable of transferring successfully in either direction with 70 of rated voltage applied to the switch terminals 4 The normal and standby contacts shall be positively interlocked mechanically and electrically to prevent simultaneous closing Main contacts shall be mechanically locked in position in both the normal and standby positions without the use of hooks , latches , magnets , or springs and shall be silver tungsten alloy protected by arcing contacts with magnetic blowouts in each pole Interlocked molded case circuit breakers will not be acceptable 5 The transfer switch shall be equipped with a safe manual operator that has been designed to prevent injury to the operating personnel if the electrical STANDBY POWER GENERATION SYSTEMS SECTION 6 - 6 2022 RevisionPagePage pageNumber7SECTION 6 – STANDBY POWER GENERATION SYSTEMS operator should suddenly become energized during manual transfer The manual operator shall provide the same contact opening and closing speed as the electrical operator to prevent a flashover from switching the main contacts slowly 6 Engine starting contacts shall be provided to start the generating plant if any phase of the normal source drops below 80 of rated voltage after a nonadjustable time delay period of 3 seconds to allow for momentary dips The transfer switch shall transfer to standby as soon as the voltage and frequency have reached 90 of rating After restoration of normal power on all phases to 90 of rated voltage , an adjustable time delay period of 0 - 30 minutes shall delay retransfer to normal power until it has had time to stabilize If the standby power source should fail during the time delay period , the time delay shall be bypassed and the switch shall return immediately to the normal source After the switch has retransferred to normal , the engine generator shall be allowed to operate at no load for an adjustable period of 5 - 30 minutes to allow it to cool before shutdown The transfer switch shall include a test switch to simulate normal power failure , a test input to simulate a normal power failure upon closure of a SCADA dry contact provided for remote start , pilot lights on the cabinet door to indicate the switch closed on normal or emergency , and four spare auxiliary contacts on the main shaft , two closed on normal and two closed on emergency All relays , timers ’ controls , wiring , and accessories to be front accessible 7 The transfer switch , complete with all timers , relays , and accessories shall be listed by Underwriters ’ Laboratories , Inc at the time of the bid opening in their Electrical Construction Materials Catalogue under Standard UL - 1008 Automatic Transfer Switches and approved for use on emergency systems The UL listing shall include the specific amperage ratings that are called for in this specification 8 Transfer switch shall have adjustable over voltage , under voltage , phase reversal , and phase loss relays for the normal power source Relays shall initiate transfer to standby if any abnormal voltage condition on the normal source occurs , including motor - generated voltages that occur during single phasing of the normal source 9 The transfer switch shall have a short circuit withstand capability of 50,000 RMS amperes symmetrical minimum To establish conformance with the above , the manufacturer must produce certified test reports from an independent testing laboratory to verify that identical samples have been subjected to three phase short circuit at 480 VACS for a minimum of 3 cycles duration , without contact damage or contact welding , and without the use of current limiting fuse protection Oscillograph traces are to be supplied to verify that the test parameters have been met 10 Transfer switch shall have one full - length door in front and shall be provided in a NEMA 4X enclosure for rack mounting PART 3 - EXECUTION STANDBY POWER GENERATION SYSTEMS SECTION 6 - 7 2022 RevisionPagePage pageNumber8SECTION 6 – STANDBY POWER GENERATION SYSTEMS 31 The equipment shall be installed as shown on the plans with a reinforced concrete foundation sized in accordance with the manufacturer’s recommendations and all applicable codes All exposed edges of concrete foundation shall have a ¾ - inch chamfer The concrete pad shall be a minimum of 12 - inches in thickness with # 5 rebar at 12 - inches OC each way The generator set concrete pad shall have a minimum of 6 - inches exposed foundation on all sides of the pad 32 Site Tests The manufacturer’s local representative shall perform an installation check , start - up and a 4 - hour minimum load test The engineer and the County utility operating staff shall be notified of the time and date of the site test Contractor shall provide a full tank of fuel prior to testing Fuel , lubricating oil , and antifreeze liquid cooled models shall be checked for conformity to the manufacturer’s recommendations under the environmental conditions present and expected Accessories that normally function while the set is standing by shall be checked prior to cranking the engine This shall include engine heaters , battery charger , generator strip heaters and remote annunciator , etc Start - up under test mode to check for exhaust leaks , path of exhaust gases , cooling air flow , movement during starting and stopping , vibration during running , normal and emergency line - to - line voltage , and phase rotation Automatic start - up by means of simulated power outage to test remote - automatic starting , transfer of load and automatic shutdown shall be performed Engine temperature , oil pressure , and battery charge level along with generator voltage , amperes , and frequency shall be monitored throughout the test Following testing and acceptance , the fuel tank shall be left at a full level , and a start - up report and spare parts must be furnished to the County 1 paper and 1 electronic copy of the O & M manual END OF SECTION STANDBY POWER GENERATION SYSTEMS SECTION 6 - 8 2022 RevisionPage