NOTEThis specification covers packaged engine-generator sets and their accessories for emergency, legally required standby, and optional standby power service in accordance with NFPA 70 Articles 700, 701, and 702, and NFPA 110. (1.1)
NOTEEach set comprises a reciprocating internal combustion engine, a directly coupled synchronous alternator, a unit-mounted controller, batteries and charging system, cooling and exhaust systems, fuel system, and an enclosure or base, furnished as a single integrated assembly listed to UL 2200. (1.2)
1.3A standby generator is part of a system and shall be coordinated with the automatic transfer switch (see Automatic Transfer SwitchesAutomatic Transfer SwitchesResolves to the current edition.sync/automatic-transfer-switches), the grounding and bonding system (see Grounding And BondingGrounding and Bonding for Electrical SystemsResolves to the current edition.sync/grounding-and-bonding), the raceways and conductors that connect it to the distribution system (see Raceways And ConduitRaceways and ConduitResolves to the current edition.sync/raceways-and-conduit and Conductors And CablesConductors and CablesResolves to the current edition.sync/conductors-and-cables), the concrete pad or structural support on which it sits (see Concrete PadsConcrete Equipment PadsResolves to the current edition.sync/concrete-pads), and the equipment identification scheme (see Equipment LabelingElectrical Equipment LabelingResolves to the current edition.sync/equipment-labeling).
NOTEThe performance commitments in this standard assume those coordinated scopes are in place. (1.4)
NOTEThis standard does not cover prime power generation in continuous duty service. (1.5)
NOTEPrime and continuous duty ratings per ISO 8528 imply different engine selection, cooling, fuel infrastructure, and maintenance assumptions and are outside scope. (1.5.1)
NOTEThis standard does not cover paralleled multi-engine plants beyond the basic provisions needed to add a future paralleling cubicle. (1.6)
1.6.1Full paralleled systems with load sharing, synchronizing, and utility paralleling per IEEE 1547 require additional engineering and shall be specified separately.
2Referenced Standards
2.1Equipment, materials, and installation shall comply with the latest adopted edition of the standards listed below.
Standard
Title
NFPA 110
Standard for Emergency and Standby Power Systems
NFPA 37
Standard for the Installation and Use of Stationary Combustion Engines and Gas Turbines
NFPA 30
Flammable and Combustible Liquids Code
NFPA 54
National Fuel Gas Code
NFPA 58
Liquefied Petroleum Gas Code
NFPA 70
National Electrical Code (Articles 445, 700, 701, 702, 705)
NFPA 70E
Standard for Electrical Safety in the Workplace
UL 2200
Stationary Engine Generator Assemblies
UL 142
Steel Aboveground Tanks for Flammable and Combustible Liquids
UL 2085
Protected Aboveground Tanks for Flammable and Combustible Liquids
UL 1236
Battery Chargers for Charging Engine-Starter Batteries
ISO 8528
Reciprocating Internal Combustion Engine Driven Alternating Current Generating Sets
Recommended Practice for Emergency and Standby Power Systems for Industrial and Commercial Applications (Orange Book)
IEEE 1547
Standard for Interconnection and Interoperability of Distributed Energy Resources with Associated Electric Power Systems Interfaces
NEMA MG 1
Motors and Generators
EGSA 100B
Performance Standard for Engine Cranking Batteries
EGSA 101P
Performance Standard for Engine Driven Generator Sets, Prime Mover
EGSA 109C
Code of Practice for Packaged Engine Generator Sets
40 CFR Part 60 Subpart IIII
Standards of Performance for Stationary Compression Ignition Internal Combustion Engines
40 CFR Part 60 Subpart JJJJ
Standards of Performance for Stationary Spark Ignition Internal Combustion Engines
40 CFR Part 63 Subpart ZZZZ
NESHAP for Stationary Reciprocating Internal Combustion Engines
40 CFR Part 1039
Control of Emissions from New and In-Use Nonroad Compression-Ignition Engines (Tier 4)
ASCE 7
Minimum Design Loads and Associated Criteria for Buildings and Other Structures
IBC
International Building Code (seismic and anchorage provisions)
ICC ES AC156
Acceptance Criteria for Seismic Certification by Shake-Table Testing
NETA ATS
Acceptance Testing Specifications for Electrical Power Equipment and Systems
2.2Where the contract documents, the adopted building code, or a referenced standard conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
3Submittals
3.1Action Submittals
3.1.1Contractor shall submit the following for the Engineer's review prior to procurement and fabrication:
Product data for the generator set, alternator, controller, battery charger, jacket water heater, enclosure, sub-base fuel tank, exhaust silencer, and all factory-supplied accessories
Dimensioned shop drawings showing plan, elevations, conduit and cable entry locations, fuel piping connections, exhaust outlet location, cooling air intake and discharge openings, and required clearances
Single-line diagram showing the generator output, neutral treatment, main line breaker, instrument transformers, and control wiring interfaces with the transfer switch
Alternator reactance data, decrement curve, and starting kVA / voltage dip analysis for the project's largest motor and step-load profile
Site-specific exhaust emissions calculation and compliance documentation for the applicable EPA standard and any state or local air quality permit
Sound data showing octave-band sound pressure and overall A-weighted level at 7 m at full load, and predicted sound at the nearest property line or sensitive receptor
Fuel consumption table at 25%, 50%, 75%, and 100% rated load, and calculated runtime at the specified tank capacity
Cooling system performance data at the design ambient temperature, including air flow, static pressure available for ductwork, and radiator restriction limits
Seismic certification documentation per ICC ES AC156 or per the project's applicable importance factor
Genset controller submittal showing NFPA 110 compliance, all configured alarms and shutdowns, and the remote annunciator point list
Factory test certificates (production tests per UL 2200 and ISO 8528) and the proposed factory witness test procedure
Action Submittals Requiredcheckbox
☑ Product data for generator and accessories
☑ Dimensioned shop drawings
☑ Single-line diagram and control interfaces
☑ Alternator reactance and starting kVA analysis
☑ Emissions compliance documentation
☑ Sound data at 7 m and at property line
☑ Fuel consumption and runtime calculation
☑ Cooling performance at design ambient
☑ Seismic certification (AC156)
☑ Controller submittal and annunciator point list
☑ Factory test plan and certificates
3.1.2Fabrication shall not proceed until the action submittals are reviewed and returned.
3.2Closeout Submittals
3.2.1Contractor shall provide the following at substantial completion before the generator is accepted into emergency or standby service:
Operation and maintenance manuals, indexed, including engine, alternator, controller, battery charger, and all accessories
As-built drawings reflecting installed conduit and fuel pipe routing, exhaust routing, and any field changes
Signed and dated NFPA 110 acceptance test record, including the on-site installation test and any required load bank test
Factory and field test reports, including infrared scan of all power terminations under load
Emissions source test report, where required by the air quality permit
Warranty documentation and the start of the warranty period (commencement date)
Spare parts inventory list with manufacturer part numbers
Owner training sign-off sheet documenting training topics and attendees
☑ Factory and field test reports with infrared scan
☐ Emissions source test report (where required)
☑ Warranty documentation with commencement date
☑ Spare parts inventory list with part numbers
☑ Owner training sign-off sheet
4Quality Assurance
4.1Manufacturer Qualifications
4.1.1The generator set shall be manufactured by a single company responsible for the engine selection, alternator selection, controller, base/enclosure, and integration.
4.1.2The manufacturer shall have a minimum of ten years documented experience producing UL 2200 listed engine-generator sets in the rating range of the project.
4.1.3The manufacturer shall maintain an ISO 9001 certified quality management system.
4.1.4A factory-authorized service organization shall be located within a service radius such that a field technician with parts can be on site within four hours of notification, 24 hours a day, throughout the warranty period.
NOTELocal service capability is critical for life safety applications; a fast unit price from a manufacturer without local service is a false economy when the set fails during an outage. (4.1.5)
4.2Source Limitations
4.2.1The complete set — engine, alternator, base, controller, battery charger, enclosure, sub-base tank where provided, and exhaust silencer — shall be furnished by the generator manufacturer as an integrated assembly listed to UL 2200.
4.2.2Component-by-component assembly by the installing Contractor is not acceptable.
NOTEUL 2200 listing depends on the integrated assembly and not on the components individually. (4.2.3)
4.3Listing and Labeling
4.3.1The complete generator set assembly shall be listed and labeled to UL 2200 by a Nationally Recognized Testing Laboratory.
4.3.2The sub-base fuel tank, where provided, shall be listed and labeled to UL 142 or UL 2085 as applicable.
4.3.3The battery charger shall be listed to UL 1236.
4.3.4The controller and its protective relaying shall be listed for the purpose.
4.4Testing Personnel Qualifications
4.4.1Field acceptance testing and commissioning shall be performed by technicians certified by NETA, EGSA, or the generator manufacturer's training program.
4.4.2Personnel performing NFPA 110 installation acceptance testing shall have documented experience commissioning at least three sets of the same general type and rating class.
5Environmental and Service Conditions
5.1The generator set shall be suitable for continuous operation, under the engine duty class selected, at the site's ambient conditions.
5.2Where site conditions exceed the standard rating basis, the set shall be derated per ISO 8528 and the alternator and engine selected accordingly.
5.3The rating shall be confirmed against the site's design ambient.
NOTEStandard rating conditions per ISO 8528 are 25°C ambient, 100 m altitude, 30 percent relative humidity, and 100 kPa barometric pressure; very few real sites match this basis exactly. (5.3.1)
5.4Ambient Temperature
5.4.1The design maximum ambient temperature at the installation shall be as indicated in the datasheet.
Design Ambient Temperature (Maximum)range
°C
40455055
NOTE40°C is the standard outdoor enclosure rating; the higher selections apply where the site design ambient exceeds it. (5.4.2)
5.4.3The cooling system shall be selected so that the engine coolant and after-cooler air temperatures remain within the engine manufacturer's limits at the design ambient with the set carrying its rated load.
5.4.4Radiator-cooled sets shall be sized for the air temperature rise through the enclosure plus the design ambient.
NOTERadiator-cooled sets require extra margin compared to a bare set in open air. (5.4.5)
5.5Altitude
5.5.1The installation altitude shall be as indicated in the datasheet.
Installation Altitudeselect
Below 500 ft (150 m) - no derating
500 to 3,300 ft (150 to 1,000 m) - verify engine derating
3,300 to 6,600 ft (1,000 to 2,000 m) - engine derating required
Above 6,600 ft (2,000 m) - consult engine manufacturer
5.5.2The published kW rating shall be the derated output at the design altitude and ambient, not the standard-condition rating.
NOTENaturally aspirated diesel engines lose roughly 3 percent of power per 1,000 ft (300 m) above 500 ft (150 m), and additional derating applies above the engine manufacturer's threshold ambient; turbocharged engines hold output longer but eventually derate as well. (5.5.3)
5.6Cold Weather Service
5.6.1The design minimum temperature at the installation shall be as indicated in the datasheet.
Design Minimum Temperatureselect
Above 0°C
0 to −10°C
−10 to −25°C
Below −25°C
NOTEThe design minimum temperature is a site climate value; the Engineer takes it from the project's design weather data and it drives the entire cold-start package. (5.6.2)
5.6.3Where the design minimum temperature is at or below 0°C, cold weather start aids shall be provided as specified in the Engine and Batteries sections.
NOTENFPA 110 requires Level 1 systems to be capable of starting within 10 seconds of receiving a start signal; meeting this in cold weather requires a properly sized jacket water heater, battery heater pad, and (for very cold climates) lube oil heating. (5.6.4)
5.7Corrosive and Coastal Environments
5.7.1Where the set is installed within 1 mile of a salt water shoreline, in heavy industrial atmospheres, or in chemically aggressive environments, the enclosure paint system, fasteners, and exposed metal components shall be specified for the corrosivity category.
5.7.2Stainless steel hardware should be substituted for plated steel at exterior fasteners.
5.7.3The enclosure shall receive an enhanced paint system as described under Enclosure.
6Ratings
6.1Continuous Output Rating (kW)
6.1.1The generator set continuous output rating at the project's site conditions and duty class shall be as indicated in the datasheet.
Generator Continuous Output (Site-Rated kW)range
kW
306010015020030040050060075010001250150017502000
Per drawings — generator schedule (deferred by default)
6.1.2The Engineer shall provide both the standard-condition rating and the site-rated kW on the generator schedule.
NOTEThe site-rated kW is the value that matters for connected-load sizing; it is the kW the set will actually deliver after derating for altitude, ambient, and any fuel selection (for example, the natural-gas rating of a dual-fuel engine is generally lower than its diesel rating). (6.1.3)
6.2Duty Class
6.2.1The generator duty class shall be as indicated in the datasheet.
Generator Duty Class (per ISO 8528)radio
● Emergency Standby Power (ESP) - variable load, limited hours
○ Limited-Time Prime (LTP) - constant load, limited annual hours
○ Prime Power (PRP) - variable load, unlimited hours
○ Continuous Operating Power (COP) - constant load, unlimited hours
NOTEFor a building emergency or standby system per NFPA 110, the Emergency Standby Power (ESP) rating is appropriate; it permits a variable load with average load not exceeding 70 percent of ESP and limited annual run hours. (6.2.2)
NOTESpecifying Prime or Continuous for a building standby application over-sizes the set and increases first cost without operational benefit; Prime and Continuous duty classes are appropriate for sets that run as the principal power source. (6.2.3)
6.3Output Voltage and Configuration
6.3.1The alternator output voltage and configuration shall be as indicated in the datasheet.
Output Voltage and Configurationselect
208Y/120V, 3Φ 4-wire
240/120V, 1Φ 3-wire
240V delta / 120V, 3Φ 4-wire (high-leg)
480Y/277V, 3Φ 4-wire
600Y/347V, 3Φ 4-wire
Per drawings — one-line diagram (deferred by default)
6.3.2The output frequency shall be as indicated in the datasheet.
Output Frequencyradio
● 60 Hz
○ 50 Hz
NOTE60 Hz is the North American norm and is the datasheet default; a 50 Hz set is a distinct engine-alternator selection at a different rated speed, available for systems that operate at that frequency. (6.3.3)
6.3.4The selected voltage shall match the transfer switch and downstream distribution.
NOTEFor commercial and institutional buildings 100 kW and above, 480Y/277V three-phase four-wire is the standard selection because it minimizes feeder copper between the set and the transfer switch; 208Y/120V is appropriate for smaller buildings whose entire distribution is 208Y/120V. (6.3.5)
6.4NFPA 110 Classification
NOTENFPA 110 classifies emergency and standby power systems by Level, Type, and Class. (6.4.1)
6.4.2The project's NFPA 110 Level, Type, and Class shall be as indicated in the datasheet.
NFPA 110 Levelradio
● Level 1 (failure to perform could result in loss of human life or serious injury)
○ Level 2 (less critical to human life and safety)
NFPA 110 Type (maximum seconds to load)select
Type 10 (10 seconds)
Type 60 (60 seconds)
Type 120 (120 seconds)
Type U (uninterruptible)
NFPA 110 Class (minimum fuel runtime at full load)select
Class 2 (2 hours)
Class 6 (6 hours)
Class 8 (8 hours)
Class 24 (24 hours)
Class 48 (48 hours)
Class 96 (96 hours)
NOTEThe combination of Level, Type, and Class drives controller requirements, fuel storage, testing, and maintenance; Level 1 systems serve loads where failure to perform could result in loss of human life or serious injury, and Level 2 systems serve loads less critical to human life. (6.4.3)
6.4.4For NFPA 70 Article 700 emergency systems, Type 10 is the minimum and shall be confirmed on commissioning.
NOTEType 60 and Type 120 are appropriate for legally required standby and optional standby loads where a longer interruption is acceptable; Type U (uninterruptible) is generally achieved by combining the generator with a UPS that bridges the engine start interval, and the generator alone is not Type U. (6.4.5)
6.4.6The project's Class shall be the larger of the value required by the AHJ and the value required by the served occupancy.
NOTEHealthcare facilities under NFPA 99 commonly require Class 96, and common-use buildings often default to Class 8. (6.4.7)
7Engine
7.1The engine shall be a four-stroke, water-cooled, reciprocating internal combustion engine rated by the engine manufacturer for use in stationary engine-generator service, complying with ISO 3046.
7.2The engine shall be selected so that, at the alternator's rated output and power factor at the site conditions, the engine operates within its continuous rating for the selected duty class.
7.3Fuel
7.3.1The engine fuel shall be as indicated in the datasheet.
Engine Fuelradio
○ Diesel (No. 2 ULSD)
○ Natural gas
○ Liquefied petroleum (LP) gas
○ Bi-fuel (diesel primary, natural gas supplement)
○ Dual-fuel (natural gas or diesel, selectable)
7.3.2The Engineer shall confirm the AHJ's position before selecting natural gas for a Level 1 system.
NOTEFuel selection is a project decision with no universally correct answer, which is why no fuel is preselected here. Diesel No. 2 ultra-low sulfur (ULSD) is the usual choice for sets serving NFPA 110 Level 1 systems because the on-site fuel inventory provides predictable runtime independent of the gas utility; natural gas eliminates on-site fuel storage but ties the set's availability to the gas utility, which is not always acceptable for life-safety loads in seismic or high-wind regions. (7.3.3)
7.3.4Combustion Air
7.3.4.1The engine shall be furnished with a dry-type air cleaner sized for the engine's full-load air flow and the design ambient air quality.
7.3.4.2Combustion air shall be drawn from outside the enclosure for sound-attenuated and walk-in enclosures, with a service indicator showing filter restriction.
7.4Engine Mechanical Components
7.4.1Each engine shall be furnished with a lube oil cooler, full-flow lube oil filtration, fuel filtration with water separation (for diesel), thermostatically controlled coolant, a flexible exhaust connection, and a starter motor sized for the engine and the design minimum temperature.
7.5Emissions
7.5.1The emissions compliance basis for the engine furnished shall be as indicated in the datasheet.
Diesel Engine EPA Tierselect
Tier 2 (existing legacy installation)
Tier 3
Tier 4 Interim
Tier 4 Final
Spark-Ignition Engine Emissions Complianceradio
○ Not applicable — compression-ignition (diesel) engine
○ 40 CFR Part 60 Subpart JJJJ (emergency rating)
○ 40 CFR Part 60 Subpart JJJJ (non-emergency rating)
7.5.2Diesel engines installed in stationary service shall comply with the applicable subpart of 40 CFR Part 60 (Subpart IIII for compression-ignition) at the manufacturing date of the engine, and with 40 CFR Part 63 Subpart ZZZZ for in-use operation where applicable.
7.5.3Spark-ignition engines on natural gas or LP shall comply with 40 CFR Part 60 Subpart JJJJ.
7.5.4Where the AHJ or air permit authorizes a lower tier for emergency-only service, the documentation supporting the lower tier shall be included with the submittal.
NOTENew compression-ignition engines manufactured to current standards meet EPA Tier 4 Final for the regulated power range under 40 CFR Part 1039. (7.5.5)
NOTETier 4 Final compliance for diesel engines in the typical commercial size range generally requires aftertreatment — diesel oxidation catalyst, diesel particulate filter, and/or selective catalytic reduction with urea (DEF) injection — depending on engine size and the engine manufacturer's certification pathway, and the aftertreatment imposes physical space, exhaust temperature, and consumable handling requirements that shall be coordinated early. (7.5.6)
7.5.7Annual Run-Hour Limitations
7.5.7.1The Engineer shall confirm the project's permit limits and document them in the O&M manual.
NOTEEPA emergency-engine designations cap non-emergency operating hours, typically at 100 hours per year for maintenance and testing combined, with further restrictions on emergency demand response participation; exceeding the limit re-classifies the engine and triggers additional emission control requirements that may not be practical to add after installation. (7.5.7.2)
7.6Start Aids
NOTEEach start aid below is fully determined by the NFPA 110 Type and the design minimum temperature already selected, so each is stated as a requirement rather than offered as a separate project selection. (7.6.1)
7.6.2Jacket Water Heater
7.6.2.1A thermostatically controlled jacket water heater shall be provided on every NFPA 110 Type 10 system and wherever the design minimum temperature is at or below 0°C.
7.6.2.2The heater shall maintain engine coolant temperature at a value that allows reliable starting within the NFPA 110 Type time.
7.6.2.3Heater wattage shall be sized for the engine displacement and the design minimum ambient.
7.6.2.4Power for the heater shall be from a dedicated branch circuit on the normal source so that the heater is energized whenever the engine is not running.
7.6.3Battery Heater Pad
7.6.3.1Where the design minimum temperature is below 0°C, a thermostatically controlled battery heater pad shall be provided so that cranking capacity is preserved.
NOTELead-acid battery cranking capacity drops sharply below 0°C, and an unheated battery in a cold enclosure may not crank a cold engine within 10 seconds. (7.6.3.2)
7.6.4Lube Oil Heater
7.6.4.1Where the design minimum temperature is below −15°C, or where the engine manufacturer requires it, a lube oil heater shall be provided.
NOTECold lube oil increases cranking torque and lengthens start time; the heater maintains the oil at a temperature that allows the engine to crank and accept load within the required time. (7.6.4.2)
8Alternator
8.1The alternator shall be a brushless, salient pole, synchronous machine with rotating field and permanent magnet generator (PMG) excitation, conforming to NEMA MG 1, Part 32, and rated for the selected duty class per ISO 8528.
8.2The alternator shall be directly coupled to the engine through a flexible coupling on a common skid.
8.3Belt-driven or remote-coupled alternators are not acceptable.
8.4Excitation
8.4.1The alternator excitation type shall be as indicated in the datasheet.
Excitation Typeradio
● Permanent magnet generator (PMG) excitation
○ Shunt excitation
NOTEPMG excitation provides reliable short-circuit current for a defined time (typically 300 percent of rated current for 10 seconds) and is recommended for any set whose loads include selective coordination requirements or large motor starting; shunt excitation collapses field current under a bolted fault and cannot reliably trip downstream overcurrent devices, which is a significant safety and selectivity issue. (8.4.2)
8.5Insulation Class and Temperature Rise
8.5.1The alternator insulation class and temperature rise shall be as indicated in the datasheet.
Alternator Insulation Class and Riseradio
○ Class H insulation, Class H temperature rise
● Class H insulation, Class F temperature rise
○ Class F insulation, Class B temperature rise
NOTEAlternator insulation classes here are the NEMA MG 1 rotating-machine letter classes, which remain the correct US designation for generator windings. (8.5.2)
NOTESpecifying Class H insulation with a Class F temperature rise is the industry recommended practice because the insulation life is materially extended by operating at a lower temperature than its limit. (8.5.3)
8.6Voltage Regulation
8.6.1The voltage regulator shall be electronic, with three-phase RMS sensing, and shall maintain steady-state voltage regulation within ±0.5 percent of rated voltage over no-load to full-load and 0.8 lagging to unity power factor.
8.6.2The regulator shall include a volts-per-hertz limiter to protect the alternator and connected loads on underspeed, an overvoltage limiter, and a separately adjustable underfrequency knee.
8.7Where a specific alternator subtransient reactance is required to limit motor-starting voltage dip, it shall be as indicated in the datasheet.
Alternator Reactance (Subtransient, Xd")radio
○ Standard reactance alternator
○ Low reactance alternator (for stiff system / motor starting)
Manufacturer's standard (by default)
8.8Where no reactance requirement is indicated, the manufacturer's standard alternator for the rating shall apply, and the manufacturer shall report the subtransient reactance and decrement curve in the action submittals.
8.9The maximum instantaneous voltage dip on step load shall be as indicated in the datasheet.
Maximum Instantaneous Voltage Dip on Step Loadrange
%
101520253035
8.10Voltage dip during the worst case starting step (typically the largest fire pump or chiller) shall not exceed the value selected.
8.11The submittal shall include a starting kVA / voltage dip analysis demonstrating compliance.
8.12The Engineer shall verify both the voltage dip during the largest motor start and the short-circuit current rating of downstream equipment before selecting a low reactance alternator.
NOTELow reactance alternators reduce voltage dip during motor starting at the cost of higher available short-circuit current, which the downstream equipment must be rated to interrupt. (8.13)
9Controller
9.1The genset controller shall be a microprocessor-based unit, listed for the purpose, mounted on the generator set with a vibration-isolated bracket, with an alphanumeric or graphical display visible from the set's normal service position.
9.2The controller shall be NFPA 110 compliant for the project's Level and Type, providing all required alarms, shutdowns, and metering.
9.3Required Functions
9.3.1The controller shall provide as a minimum the following functions:
Cranking and starting per the selected NFPA 110 Type
Cool-down cycle on transfer back to normal (engine continues to run unloaded for a programmable period)
Generator output metering (voltage, current, kW, kVAR, kVA, kWh, power factor, frequency, and run hours)
Programmable exerciser to start and (optionally) load the set on a periodic schedule
Programmable cool-down and warm-up times
Alarm log and event history with date and time stamp
Communication interface (Modbus TCP/IP at a minimum) for integration with the building management system
9.3.2The controller communications protocol shall be as indicated in the datasheet.
Controller Communications Protocolselect
Modbus RTU (RS-485)
Modbus TCP/IP (Ethernet)
BACnet IP
DNP3
Modbus TCP/IP and BACnet IP
9.4NFPA 110 Alarms and Shutdowns
NOTEThe alarm and shutdown set is fully determined by the NFPA 110 Level already selected, so it is stated here as a requirement rather than offered as a second selection. (9.4.1)
9.4.2The controller shall be configured for the full alarm and shutdown set required by the project Level.
NOTEFor Level 1 systems, NFPA 110 Table 4.7.3 requires specific alarms and shutdowns including overcrank, low coolant temperature, high coolant temperature pre-alarm and shutdown, low oil pressure pre-alarm and shutdown, overspeed shutdown, low fuel pre-alarm, low coolant level, battery charger malfunction, low battery voltage, and EPS supplying load. (9.4.3)
9.5Remote Annunciator
9.5.1A remote annunciator shall be provided per NFPA 110 4.6.4 at a continuously monitored location outside the generator room, as indicated on the contract documents.
NOTEThe fire command center, the security desk, and the facility operations room are the usual locations. (9.5.2)
9.5.3The remote annunciator communication path shall be as indicated in the datasheet.
Remote Annunciator Communicationsradio
● Dedicated copper run from the controller in two separate raceways
○ Network-attached (IP) annunciator with redundant link
9.5.4The annunciator shall display all required NFPA 110 alarms with a common audible alarm, a means to silence the audible, and a means to test the lamps.
9.5.5NFPA 110 requires the wiring from the controller to the annunciator to be supervised.
NOTEThe most common implementation is a dedicated copper run; a network-attached annunciator is acceptable where the network meets the supervision requirements and the network is itself supplied from the standby system. (9.5.6)
9.6Main Line Circuit Breaker
9.6.1A main line circuit breaker shall be provided on the generator set output per NEC 445.18, sized for the alternator's rated output.
9.6.2The breaker trip unit shall be as indicated in the datasheet.
9.6.3The breaker shall be molded case or insulated case as appropriate and shall be field-accessible for maintenance and testing.
NOTEAn electronic trip unit is required wherever the generator breaker participates in a selective coordination study; a thermal-magnetic unit remains acceptable on smaller sets that do not. (9.6.4)
10Cooling System
10.1The cooling system shall be sized for the engine's full-load heat rejection at the site design ambient, with the air flow path that the enclosure or room imposes.
10.2The cooling arrangement shall be as indicated in the datasheet.
○ City water (heat exchanger to building cooling system)
10.3City-water cooling shall not be used for NFPA 110 Level 1 systems because the cooling source must remain available during the same events that may have caused the outage.
NOTEThe usual arrangement is a unit-mounted radiator with a blower fan driven by the engine, drawing air from one face of the enclosure and discharging through the radiator; for very large sets, sets in walk-in enclosures with sound attenuation, or sets inside buildings without acceptable air flow, a remote radiator or heat exchanger arrangement may be required. (10.4)
10.5Radiator
10.5.1The radiator fan drive shall be as indicated in the datasheet.
Radiator Fan Driveradio
● Engine-driven (belt or direct)
○ Electric (separately driven)
10.5.2The engine coolant shall be as indicated in the datasheet.
Coolantselect
50/50 ethylene glycol / water
50/50 propylene glycol / water
Pre-mixed inhibited long-life coolant
10.5.3The radiator shall be sized for the engine manufacturer's published heat rejection at the site ambient with at least 10°C margin on coolant outlet temperature.
10.5.4Radiator core construction shall be copper-brass or aluminum, with corrosion protection appropriate to the environment.
10.5.5Aluminum cores in salt air shall not be specified.
10.6Coolant Recovery and Make-up
10.6.1A coolant recovery bottle shall be provided so that overflow on thermal expansion does not result in coolant loss.
10.6.2For unattended sets or sets in remote locations, a low coolant level pre-alarm shall be wired to the controller and the remote annunciator.
11Fuel System
11.1Diesel Fuel Storage
11.1.1The diesel fuel storage configuration shall be as indicated in the datasheet.
Diesel Fuel Storage Configurationradio
● Sub-base tank at the generator
○ External aboveground bulk tank with day tank at the generator
○ Underground bulk tank with day tank at the generator
11.1.2Sub-Base Fuel Tank
NOTEA sub-base tank is a fuel tank constructed as the base of the generator set, listed to UL 142 or UL 2085, carrying the set's weight and providing its fuel storage in one assembly. (11.1.2.1)
11.1.2.2The sub-base tank capacity shall be as indicated in the datasheet.
Sub-Base Tank Capacityrange
gal
50100250500100015002000250030004000
Per drawings — generator schedule (deferred by default)
NOTETank construction is set by the applicable fire and environmental code, the spill-containment approach, and the AHJ; a UL 2085 protected tank is required where the set sits close to a building or a property line and the AHJ enforces the fire-rated construction provisions of NFPA 30 and NFPA 37. (11.1.2.3)
11.1.2.4The sub-base tank construction shall be as indicated in the datasheet.
Sub-Base Tank Constructionradio
○ Single-wall steel (UL 142)
○ Double-wall steel with interstitial space (UL 142)
● Double-wall with interstitial leak detection sensor
○ Concrete-encased UL 2085 (two-hour fire rated)
NOTESub-base tanks are practical up to roughly 4,000 gal (15,000 L); larger storage typically requires an external bulk tank with a smaller day tank at the set. (11.1.2.5)
11.1.2.6The tank capacity shall provide the NFPA 110 Class runtime at the alternator's full-load fuel consumption.
11.1.2.7The submittal shall include a fuel consumption table at 25, 50, 75, and 100 percent load and the calculated runtime so that the Engineer can confirm that the selected tank meets the Class requirement.
NOTEDouble-wall construction with interstitial leak detection is the default because it provides secondary containment without requiring a separate concrete or steel dike, and the leak detector provides early warning of either a primary tank failure or condensation in the interstitial space; single-wall tanks require a separate containment basin sized for the tank capacity per NFPA 30. (11.1.2.8)
11.1.2.9The tank shall be furnished with normal and emergency vents per NFPA 30, a fill connection with overfill protection per NFPA 30, a level indicator readable without opening the tank, a low-fuel pre-alarm contact wired to the controller, and a fuel return port.
11.1.2.10Interconnection between an external tank and a day tank shall include a transfer pump, day tank float controls, and an overflow return to the bulk tank.
11.1.3Fuel Quality
11.1.3.1Diesel fuel shall be ultra-low sulfur (ULSD), No. 2-D per ASTM D975, with a cold-flow point suitable for the climate.
11.1.3.2The Owner's operating instructions shall include a fuel quality program: at minimum, quarterly testing for water, particulates, and microbial growth, and a fuel polishing program for sets stored at high fill levels for extended periods.
11.2Natural Gas and LP Supply
11.2.1Where a specific gas supply pressure at the generator is required, it shall be as indicated in the datasheet.
Natural Gas Supply Pressure at Generatorselect
Low pressure (less than 1 psig)
Medium pressure (1 to 5 psig)
Elevated pressure (5 to 15 psig)
Manufacturer's standard (by default)
11.2.2Where no supply pressure is indicated, the engine manufacturer's required inlet pressure range shall govern, and the manufacturer shall state that range in the action submittals.
11.2.3Where the set is fueled by natural gas or LP, the supply piping shall comply with NFPA 54 (natural gas) or NFPA 58 (LP), be sized for the engine's full-load fuel demand at the worst-case supply pressure, and terminate with a manual shutoff valve and a flexible connector at the engine.
11.2.4A solenoid valve interlocked with the controller shall close on engine shutdown.
11.2.5The supply pressure at the engine inlet, with the engine at full load, shall remain within the manufacturer's required range.
11.2.6The supply piping shall be sized with margin and verified at commissioning.
NOTEInadequate gas supply pressure at full load is one of the most common causes of NFPA 110 test failures on natural-gas sets. (11.2.7)
12Exhaust System
12.1The exhaust system shall convey engine exhaust from the engine outlet to a discharge point that does not allow re-entry into the building, into the generator combustion air, or to areas where people congregate.
12.2The exhaust system shall include a silencer sized for the project's sound attenuation requirement, a flexible exhaust connection between the engine and the silencer, condensate drains at low points, and aftertreatment components where required for emissions compliance.
12.3Silencer Selection
12.3.1The exhaust silencer grade shall be as indicated in the datasheet.
Exhaust Silencer Gradeselect
Industrial (12 to 18 dB(A) insertion loss)
Residential (18 to 25 dB(A) insertion loss)
Critical / Hospital (25 to 35 dB(A) insertion loss)
Super-critical (above 35 dB(A) insertion loss)
12.3.2Silencer grade shall be selected to achieve the project's sound limit at the nearest sensitive receptor.
12.3.3The silencer's back-pressure shall not exceed the engine manufacturer's allowable back-pressure at full load.
NOTEExcess back-pressure reduces power and increases exhaust temperature, which can damage the engine. (12.3.4)
12.4Exhaust Routing
12.4.1The exhaust shall be routed in seamless steel pipe with welded or flanged joints, supported clear of combustible construction with the clearances of NFPA 37 maintained.
12.4.2The exhaust pipe material shall be as indicated in the datasheet.
Exhaust Pipe Materialradio
● Schedule 40 carbon steel
○ Schedule 80 carbon steel
○ Stainless steel (corrosive environments or condensate)
12.4.3The extent of exhaust pipe insulation shall be as indicated in the datasheet.
Exhaust Pipe Insulationradio
○ Insulated where exposed within 8 ft of personnel routes
● Insulated entire run inside building
○ Not insulated (fully outdoor routing)
12.4.4Exhaust pipe shall be insulated wherever it is exposed to personnel or to combustible materials, whichever extent is selected.
12.4.5The discharge shall point away from building air intakes, with the separation from openings in the building required by NFPA 37.
12.4.6A condensate trap and drain shall be provided at the low point of any exhaust run that can collect condensate, with discharge to a suitable waste connection.
12.4.7Exhaust condensate is acidic and shall not be discharged onto building materials or to a storm drain.
12.5Aftertreatment
12.5.1Where the engine requires aftertreatment to meet EPA Tier 4 Final or another applicable standard, the diesel oxidation catalyst, diesel particulate filter, and/or SCR catalyst shall be furnished by the generator manufacturer as part of the exhaust system, with all sensors and the DEF (urea) tank and dosing system as applicable.
12.5.2The aftertreatment shall be sized for the engine and located so that the exhaust temperature at its inlet remains above the catalyst's activation temperature during the project's typical operating cycle.
13Enclosure and Sound Attenuation
13.1The enclosure type shall be as indicated in the datasheet.
13.2The maximum sound pressure at full load shall be as indicated in the datasheet.
Maximum Sound Pressure at 7 m (Full Load)range
dB(A)
60657072758085
Per drawings — generator schedule (deferred by default)
NOTEThe sound limit is set by the local noise ordinance and the nearest sensitive receptor, so the Engineer records it on the generator schedule rather than the standard preselecting a decibel figure. Unlike transformers, engine generators have no consensus-standard sound table indexed to rating against which a relative limit could be written. (13.3)
NOTEAn open set is appropriate where the generator is installed inside a building room dedicated to it and the room provides weather protection, ventilation, and sound attenuation; a weather-protective enclosure is the minimum for outdoor installations, and sound-attenuated and walk-in enclosures incorporate acoustic lining, sound-attenuating intake and discharge openings, and exhaust silencer integration to meet a specified sound limit. (13.4)
13.5The sound rating shall be specified at the manufacturer's standard measurement condition (typically 7 m from the enclosure under free-field conditions at the rated load).
13.6The Engineer shall verify property line compliance separately.
NOTESound at the property line will generally be lower than the 7 m value because of distance attenuation, but reflections, intervening surfaces, and other sources may complicate the relationship. (13.7)
13.8Enclosure Construction
13.8.1The enclosure material shall be as indicated in the datasheet.
Enclosure Materialradio
● Galvanized steel with powder coat
○ Aluminum (coastal applications)
○ Stainless steel (severe corrosion)
13.8.2The enclosure shall be fabricated from minimum 14 gauge steel with all seams welded or sealed, internal acoustic lining selected for moisture and fire resistance, hinged and lockable access doors on both sides for engine and alternator service, and a removable end panel or roof for major component removal.
13.8.3The enclosure paint system shall be a polyester powder coat over corrosion-resistant primer with a minimum total dry film thickness of 3 mils; coastal and industrial environments shall receive an enhanced 5 mil minimum system.
13.9Ventilation Openings
13.9.1Intake and discharge openings shall be sized for the radiator air flow plus the combustion air, with motorized or gravity louvers that close when the engine is not running to keep wind-driven rain, snow, and animals out of the enclosure.
13.9.2Louvers shall open before cranking begins so that they do not obstruct the radiator air path on starting.
14Batteries and Charger
14.1Starting Batteries
14.1.1The starting battery type shall be as indicated in the datasheet.
Battery Typeradio
○ Flooded lead-acid
● Absorbed glass mat (AGM) sealed lead-acid
14.1.2The starting battery system voltage shall be as indicated in the datasheet.
Battery Voltageradio
○ 12V
○ 24V
Manufacturer's standard (by default)
14.1.3Where no battery voltage is indicated, the starting system voltage shall be the engine manufacturer's standard for the engine furnished, and the manufacturer shall state it in the action submittals.
14.1.4Cranking batteries shall be lead-acid (flooded or AGM), sized for the engine manufacturer's required cranking capacity at the design minimum temperature, conforming to EGSA 100B, mounted in a vibration-resistant rack on the set or in the enclosure.
14.1.5NFPA 110 4.7.4 requires the battery to be capable of three complete cranking cycles at the design temperature without exceeding the manufacturer's limits.
NOTEAGM batteries are recommended over flooded for stationary generator service because they tolerate vibration better, do not require watering, do not vent acid gases in normal service, and are orientation-independent; flooded batteries remain acceptable where the lower first cost is preferred and the Owner has an established maintenance program. (14.1.6)
14.2Battery Charger
14.2.1A two-rate (float / equalize), temperature-compensated battery charger listed to UL 1236 shall be provided.
14.2.2Where a specific charger output rating is required, it shall be as indicated in the datasheet.
Battery Charger Ratingrange
A
51020
14.2.3Where no charger rating is indicated, the charger shall be sized to the battery manufacturer's recommended charge rate for the battery furnished, and the rating shall be stated in the action submittals.
14.2.4The charger shall maintain the battery at float voltage during normal standby and transition to bulk/absorption charging after an engine start without sulfating the battery on extended floats.
14.2.5A battery charger malfunction contact shall be wired to the controller per NFPA 110.
14.2.6The charger shall be powered from a dedicated branch circuit on the normal source, and shall be wired so that on loss of normal power the charger does not become a load on the generator.
14.2.7The charger output shall include reverse polarity protection and short-circuit protection.
15Vibration Isolation and Seismic
15.1Vibration Isolation
15.1.1The generator set shall be mounted on factory-installed vibration isolators between the engine-alternator skid and the base or sub-base tank.
15.1.2The vibration isolation arrangement shall be as indicated in the datasheet.
Vibration Isolationradio
○ Factory isolation only (outdoor pad-mount, no occupied space below)
○ Factory isolation plus external spring isolators with seismic restraints
○ Factory isolation plus restrained spring isolators on inertia base
15.1.3Where the set is installed inside an occupied building, additional spring isolators with seismic restraints shall be provided between the base and the housekeeping pad to limit structure-borne noise transmission.
NOTEA restrained spring isolator with an inertia base is appropriate where the set is installed above or adjacent to acoustically sensitive occupied spaces and the additional mass and isolation are needed to meet a noise criterion. (15.1.4)
15.2Seismic Certification and Anchorage
15.2.1The seismic certification basis shall be as indicated in the datasheet.
Seismic Certification Basisselect
Not required (no seismic risk)
ASCE 7 Seismic Design Category C - Importance Factor 1.0
ASCE 7 SDC D, E, or F - Importance Factor 1.0
ASCE 7 SDC D, E, or F - Importance Factor 1.5 (essential facility)
OSHPD pre-approval (California healthcare)
Per drawings — structural drawings (deferred by default)
NOTEThe Seismic Design Category and Importance Factor are established by the project's structural design and are recorded on the structural drawings; the electrical scope adopts them rather than setting them. (15.2.2)
15.2.3Where seismic certification is required, the complete generator set as assembled — including engine, alternator, controller, sub-base tank, and enclosure — shall be certified by shake-table testing per ICC ES AC156 or by analysis acceptable to the AHJ.
15.2.4Anchorage to the housekeeping pad shall be by post-installed anchors sized for the certified base shear and overturning moment, installed per the certification documentation.
15.2.5Anchor design shall be coordinated with Concrete PadsConcrete Equipment PadsResolves to the current edition.sync/concrete-pads.
15.2.6Where the project is an essential facility per ASCE 7 (Importance Factor 1.5), the set shall also be functional after the design seismic event; certification shall demonstrate operability and not only structural survival.
16Testing
16.1Factory Tests
16.1.1The manufacturer shall perform the following production tests on every set prior to shipment per UL 2200 and ISO 8528-6:
Full-load run at rated kW, voltage, and frequency
Single-step rated load pickup
Safety shutdown verification (overspeed, low oil pressure, high coolant temperature)
Voltage regulation test through the load range
Phase rotation and polarity verification
Insulation resistance test on the alternator
Visual and dimensional inspection
16.1.2The extent of factory witness testing shall be as indicated in the datasheet.
Factory Witness Testradio
○ Not required beyond manufacturer's production tests
● Certified test report (unwitnessed)
○ Witnessed by Owner's representative
○ Witnessed and instrumented to ISO 8528-6 test protocol
16.1.3Where witnessed testing is specified, the manufacturer shall provide at least two weeks notice of test readiness and submit the test procedure for review.
16.2Field Acceptance Tests
16.2.1The Contractor shall perform the NFPA 110 installation acceptance test on the completed installation, per NFPA 110 Chapter 7, including as a minimum:
Cold start test demonstrating the NFPA 110 Type time from start signal to load acceptance
A minimum of two hours of operation at not less than 30 percent of the rated load, with one of the loads being a step load representative of the building's largest single step
Verification of all NFPA 110 alarms and shutdowns
Verification of the remote annunciator function
Transfer and re-transfer testing with the automatic transfer switch
Verification of cool-down operation on return to normal source
Functional test of the exerciser and any load bank interface
16.2.2The field load bank test scope shall be as indicated in the datasheet.
Field Load Bank Testselect
Building loads only (where they meet NFPA 110 30 percent threshold)
Load bank to NFPA 110 minimum (typically 30 percent)
Load bank to 100 percent of rated kW for two hours
Load bank to 100 percent and four-hour endurance run
NOTEA 100 percent rated load bank test is recommended at acceptance even when building loads alone would meet NFPA 110, because most building loads at the time of commissioning are well below the generator's rating, and wet stacking on a chronically under-loaded diesel is a common in-service problem. (16.2.3)
16.3Commissioning Documentation
16.3.1The Contractor shall provide a written, signed NFPA 110 installation acceptance test record.
16.3.2The witness to the NFPA 110 acceptance test shall be as indicated in the datasheet.
NFPA 110 Acceptance Test Witnessradio
○ Authority Having Jurisdiction witness required
○ Owner's commissioning agent witness
○ Engineer of Record witness
○ Test report certified by Contractor
NOTEWhether the AHJ elects to witness is the AHJ's determination on each project, so no witness arrangement is preselected here. (16.3.3)
16.3.4The record shall include the date of test, the technicians performing the test, the instruments used, the measured start time, the load profile, observed alarms, corrective actions if any, and the AHJ witness signature where the AHJ elects to witness.
16.4Infrared Scanning
16.4.1The infrared thermographic inspection scope shall be as indicated in the datasheet.
Infrared Thermographic Inspectionradio
● Initial scan within 90 days plus follow-up at 11 months
○ Initial scan within 90 days
○ Not required
16.4.2Each scheduled scan shall cover all power terminations and bus connections and shall be performed under full load.
NOTEThe follow-up scan at 11 months catches connections that loosen during the first year of thermal cycling, while the equipment is still under warranty. (16.4.3)
16.4.4Connections showing more than 10°C rise above ambient or 5°C rise above similar adjacent connections shall be corrected.
17Installation
17.1Concrete Housekeeping Pad
17.1.1The generator set shall be set on a reinforced concrete housekeeping pad sized to extend at least 6 in. beyond the set's footprint on all sides, with a minimum thickness sufficient to accept the anchor embedment depth required by the seismic anchorage design, and an upper surface elevation of at least 4 in. above the surrounding floor or grade.
17.1.2Pad construction shall be coordinated with Concrete PadsConcrete Equipment PadsResolves to the current edition.sync/concrete-pads and with the structural drawings.
17.1.3Conduit penetrations, fuel line penetrations, and grounding electrode connection points shall be cast or sleeved into the pad before concrete placement.
NOTEDrilling and chipping the housekeeping pad after the fact for cable entries is poor practice and weakens the anchorage. (17.1.4)
17.2Clearances
17.2.1The service clearance provided around the set shall be as indicated in the datasheet.
Service Clearance Around Setselect
NFPA 70 110.26 working space minimum
The greater of NFPA 70 110.26 and the engine manufacturer's published service access requirement
Walk-around access on all four sides
NOTEThe codes set a floor; the clearance actually provided is a site-planning decision, and walk-around access on all four sides is frequently specified where the Owner's maintenance staff services the set in place, so the field carries no default. (17.2.2)
17.2.3Working clearances around the generator set and its controller, transfer switch, and main line breaker shall comply with NFPA 70 Article 110.26.
17.2.4The Contractor shall confirm that the planned location accommodates the larger of the NFPA 70 working clearances and the NFPA 37 clearances between the engine and combustible construction, between the exhaust pipe and combustibles, and around the enclosure for service access.
17.3Conduit, Cable, and Grounding
17.3.1The generator neutral treatment shall be as indicated in the datasheet.
Generator Neutral Treatmentradio
○ Switched neutral at ATS - generator is a separately derived system
○ Solid (non-switched) neutral at ATS - generator is not separately derived
Per drawings — one-line diagram (deferred by default)
17.3.2Power and control conduit entries shall be located per the shop drawings, with watertight fittings on outdoor enclosures and bushings or hubs as required for the cable system.
17.3.3Conduits shall be coordinated with Raceways And ConduitRaceways and ConduitResolves to the current edition.sync/raceways-and-conduit and conductors with Conductors And CablesConductors and CablesResolves to the current edition.sync/conductors-and-cables.
17.3.4The generator frame and the alternator neutral (where applicable) shall be grounded per NEC Article 250 and per Grounding And BondingGrounding and Bonding for Electrical SystemsResolves to the current edition.sync/grounding-and-bonding.
17.3.5The Contractor shall confirm the transfer switch arrangement before bonding the neutral, and shall coordinate with the transfer switch submittal under Automatic Transfer SwitchesAutomatic Transfer SwitchesResolves to the current edition.sync/automatic-transfer-switches.
17.3.6A generator that is a separately derived system shall have its neutral bonded to ground at the set and a grounding electrode connection per NEC 250.30.
17.3.7A generator with a solid (non-switched) neutral through the ATS shall not have its neutral bonded to ground at the set, because the service main bonding jumper already provides the system bond and a second bond creates objectionable parallel neutral current.
NOTEWhether the generator is a separately derived system depends on the transfer switch's neutral treatment. (17.3.8)
17.4Fuel and Exhaust
17.4.1Fuel piping, fuel tank vents, and fuel fill connections shall be installed per NFPA 30 (diesel) or NFPA 54 / 58 (gas).
17.4.2Exhaust piping shall be supported and routed per NFPA 37 with the required clearances from combustibles, and discharge shall comply with the air permit and with NFPA 37 separation from building openings.
18Identification and Labeling
18.1Field-installed labels shall be provided as indicated in the datasheet.
Generator Identificationcheckbox
☑ Equipment designation matched to one-line diagram
☑ EPS supply identification per NEC 700.10(A) (emergency systems)
☑ Available fault current label per NEC 110.24
☑ Arc flash warning label per NFPA 70E and IEEE 1584
☑ NFPA 110 Level and Type identification at the set
☐ Emergency power source identification at served panelboards
18.2Each emergency system component, including the generator, shall be marked at its enclosure as part of an emergency system per NEC 700.10(A).
18.3The available fault current at the generator main breaker and at the load side of the transfer switch shall be calculated, labeled, and dated per NEC 110.24.
18.4Equipment labeling format shall follow Equipment LabelingElectrical Equipment LabelingResolves to the current edition.sync/equipment-labeling conventions.
19Delivery, Storage, and Handling
19.1The generator set shall be shipped from the factory with the engine pre-filled with the manufacturer's recommended lubricant, the cooling system filled or drained-and-tagged per the storage plan, batteries shipped dry or wet per the manufacturer's recommendation, and all shipping braces and weather seals in place.
19.2Sets stored on site for more than 30 days before energization shall be stored under cover, with the jacket water heater and battery charger connected to a temporary source if available, and shall be turned over periodically per the manufacturer's storage instructions.
19.3The Contractor shall verify clearances along the entire delivery path — gates, doors, ramps, elevators, structural floor capacity — before the set arrives.
NOTELarge sets are routinely re-routed at the last minute because someone discovered a doorway that the set will not pass through; this is avoidable with a pre-delivery survey. (19.4)
20Warranty
20.1The manufacturer shall warrant each generator set for the period indicated in the datasheet.
Warranty Periodselect
1 year from substantial completion or first start, whichever is earlier
2 years / 1,000 hours, whichever occurs first
5 years / 1,500 hours extended (premium)
20.2The warranty shall cover defects in materials and workmanship under normal standby use.
20.3The warranty period shall include the manufacturer's commitment to provide a field-service technician on site within four hours of notification of a critical failure, 24 hours per day, for the duration of the warranty.
NOTEOwners commonly extend the warranty to five years on critical-mission installations. (20.4)
21Spare Parts and Maintenance Materials
21.1Spare parts shall be furnished as indicated in the datasheet.
Spare Parts Packagecheckbox
☑ One set of engine filters (oil, fuel, air, coolant)
☑ One set of belts and hoses
☐ Spare battery (matched to installed set)
☑ Spare control fuses and indicating lamps
☑ Touch-up paint matching enclosure finish
21.2Spare parts shall be stored on site in a labeled cabinet in the generator room or electrical room.
21.3The O&M manual shall list the part numbers, supplier, and reorder lead times so that the Owner can replenish without relying on the original Contractor.
21.4Owner Training
21.4.1The generator manufacturer's authorized service representative shall provide on-site training to the Owner's operating personnel for the duration indicated in the datasheet, and in no case less than four hours.
Owner Training Durationrange
hours
4816
21.4.2An 8-hour session shall be split between operations and maintenance, and a 16-hour session shall be split between operations, maintenance, and troubleshooting.
21.4.3Training shall cover normal operation, the controller interface, the exerciser configuration, the alarm and shutdown response procedure, NFPA 110 testing and recordkeeping, and routine maintenance intervals.
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"Engine Generators." SynC Standards. Licensed under CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/). Source: https://synergyinconstruction.com/wiki/sync/generators — reference material only; not professional engineering advice and provided without warranty. Verify against governing codes and have a licensed professional review before use.