tains important instructions that should be followed
during installation and maintenance of the generator and batteries.
Before operating the generator set (genset),
read the Operator’s Manual and become familiar
with it and the equipment. Safe and efficient op-
eration can be achieved only if the equipment is
properly operated and maintained. Many acci-
dents are caused by failure to follow fundamental
rules and precautions.
The following symbols, found throughout this
manual, alert you to potentially dangerous conditions to the operator, service personnel, or the
equipment.
DANGER
hazards which will result in severe personal injury or death.
WARNING
unsafe practice which can result in severe personal injury or death.
This symbol warns of immediate
This symbol refers to a hazard or
emit a highly explosive hydrogen gas that can
be ignited by arcing, sparking, smoking, etc.
EXHAUST GASES ARE DEADLY
• Provide an adequate exhaust system to properly expel discharged gases away from enclosed or sheltered areas and areas where individuals are likely to congregate. Visually and
audibly inspect the exhaust daily for leaks per
the maintenance schedule. Make sure that exhaust manifolds are secured and not warped.
Do not use exhaust gases to heat a compartment. Exhaust height should be tall enough to
help clear gases, avoid accumulation of snow
or in accordance with local mechanical code.
• Be sure the unit is well ventilated.
• Engine exhaust and some of its constituents
are k nown to the state of California to cause
cancer, birth defects, and other reproductive
harm.
MOVING PARTS CAN CAUSE SEVERE
PERSONAL INJURY OR DEATH
CAUTION
unsafe practice which can result in personal injury or product or property damage.
This symbol refers to a hazard or
FUEL AND FUMES ARE FLAMMABLE
Fire, explosion, and personal injury or death can result from improper practices.
• Natural gas is lighter than air, and will tend to
gather under hoods. Propane is heavier than
air, and will tend to gather in sumps or low
areas. NFPA code requires all persons handling propane to be trained and qualified.
• Be sure all fuel supplies have a positive shutoff
valve.
• Be sure battery area has been well-ventilated
prior to servicing near it. Lead-acid batteries
• Keep your hands, clothing, and jewelry away
from moving parts. Loose clothing and jewelry
can become caught in moving parts.
• Before starting work on the generator set, disconnect battery charger from its AC source,
then disconnect starting batteries, negative (-)
cable first. This will prevent accidental starting.
• To prevent accidental air starting, make sure
the air supply line is connected until the generator set is ready to start.
• Make sure that fasteners on the generator set
are secure. Tighten supports and clamps, keep
guards in position over fans, drive belts, etc.
• If adjustment must be made while the unit is
running, use extreme caution around hot manifolds, moving parts, etc.
iii
Page 6
ELECTRICAL SHOCK CAN CAUSE
SEVERE PERSONAL INJURY OR DEATH
• Remove electric power before removing protective shields or touching electrical equipment. Use rubber insulative mats placed on dry
wood platforms over floors that are metal or
concrete when around electrical equipment.
Do not wear damp clothing (particularly wet
shoes) or allow skin surface to be damp when
handling electrical equipment. Do not wear
jewelry. Jewelry can short out electrical contacts and cause shock or burning.
• Use extreme caution when working on electrical components. High voltages can cause injury or death. DO NOT tamper with interlocks.
• Follow all applicable state and local electrical
codes. Have all electrical installations performed by a qualified licensed electrician. Tag
and lock open switches to avoid accidental closure.
• DO NOT CONNECT GENERATOR SET DIRECTLY TO ANY BUILDING ELECTRICAL
SYSTEM. Hazardous voltages can flow from
the generator set into the utility line. This
creates a potential for electrocution or property
damage. Connect only through an approved
isolation switch or an approved paralleling device.
MEDIUM VOLTAGE GENERATOR SETS
(601V to 15kV)
• Medium voltage acts differently than low voltage. Special equipment and training is required
to work on or around medium voltage equipment. Operation and maintenance must b e
done only by persons trained and qualified to
work on such devices. Improper use or procedures will result in severe personal injury or
death.
GENERAL SAFETY PRECAUTIONS
• Coolants under pressure have a higher boiling
point than water. DO NOT open a radiator or
heat exchanger pressure cap while the engine
is running. Allow the generator set to cool and
bleed the system pressure first.
• Used engine oils have been identified by some
state or federal agencies as causing cancer or
reproductive toxicity. When checking or changing engine oil, take care not to ingest, breathe
the fumes, or contact used oil.
• Keep multi-class ABC fire extinguishers handy.
Class A fires involve ordinary combustible materials such as wood and cloth; Class B fires,
combustible and flammable liquid fuels and
gaseous fuels; Class C fires, live electrical
equipment. (ref. NFPA No. 10).
• Make sure that rags are not left on or near the
engine.
• Make sure generator set is mounted in a manner to prevent combustible materials from accumulating under the unit.
• Remove all unnecessary grease and oil from
the unit. Accumulated grease and oil can cause
overheating and engine damage which present
a potential fire hazard.
• Keep the generator set and the surrounding
area clean and free from obstructions. Remove
any debris from the set and keep the floor clean
and dry.
• Do not work on this equipment when mentally
or physically fatigued, or after consuming any
alcohol or drug that makes the operation of
equipment unsafe.
• Substances in exhaust gases have been identified by some state or federal agencies as
causing cancer or reproductive toxicity. Take
care not to breath or ingest or come into contact
with exhaust gases.
• Do not work on energized equipment. Unauthorized personnel must not be permitted near
energized equipment. Due to the nature of medium voltage electrical equipment, induced
voltage remains even after the equipment is
disconnected from the power source. Plan the
time for maintenance with authorized personnel so that the equipment can be de-energized
and safely grounded.
• Do not store any flammable liquids, such as
fuel, cleaners, oil, etc., near the generator set.
A fire or explosion could result.
• Wear hearing protection when going near an
operating generator set.
• To prevent serious burns, avoid contact with
hot metal parts such as radiator, turbo charger
and exhaust system.
KEEP THIS MANUAL NEAR THE GENSET FOR EASY REFERENCE
iv
Page 7
1. Introduction
ABOUT THIS MANUAL
This manual provides installation instructions for
the generator set models listed on the front cover.
This includes the following information:
Mounting Recommendations - for fastening
generator set to base and space requirements
for normal operation and service.
Mechanical and Electrical Connections covers most aspects of the generator set installation.
Installation Checklist -- reference checks
upon completion of installation.
Prestart -- checklist of items or procedures
needed to prepare generator set for operation.
Initial Startup -- test complete system to ensure proper installation, satisfactory performance, and safe operation. Refer to Operators
Manual for troubleshooting information.
This manual DOES NOT provide application information for selecting a generator set or designing the
complete installation. If it is necessary to design the
various integrated systems (fuel, exhaust, cooling,
etc.), additional information is required. Review
standard installation practices. For engineering
data specific to the generator set, refer to the Speci-fication and Data Sheets. For application information, refer to the Application Manual for LiquidCooled Generator Sets (T030) found in the Cummins Power Generation Power Suite Library availableonCD
1
.
INSTALLATION OVERVIEW
These installation recommendations apply to typi cal installations with standard model generator
sets. Whenever possible, these recommendations
also cover factory designed options or modifications. However, because of the many variables in
any installation, it is not possible to provide specific
recommendations for every situation. If there are
any questions not answered by this manual, contact
your nearest Cummins Power Generation distributor for assistance.
A power system must be carefully planned and correctly installed for proper operation. This involves
two essential elements: application and installation.
Application
Application (as it applies to generator set installations) refers to the design of the complete power
system that usually includes power distribution
equipment, transfer switches, ventilation equipment, mounting pads, and cooling, exhaust, and
fuel systems. Each component must be correctly
designed so the complete system will function as intended. Application and design is an engineering
function generally done by specifying engineers or
other trained specialists. Specifying engineers or
other trained specialists are responsible for the de sign of the complete power system and for selecting
the materials and products required.
Installation
Installation refers to the actual set-up and assembly
of the power system. The installers set up and connect the various components of the system as specified in the system design plan. The complexity of
the system normally requires the special skills of
qualified electricians, plumbers, sheet metal workers, etc. to complete the v arious segments of the
installation. This is necessary so all components
are assembled using standard methods and practices. Figure 1-1 provides a view of a typical genset.
1.Alternatively, go to the WEB site, http://www.cumminspower.com/library/appengineering/appengineering.jhtml, to view and
print the application manual.
1-1
Page 8
Safety Considerations
The generator set has been carefully designed to
provide safe and efficient service when properly
installed, maintained, and operated. However, the
overall safety and reliability of the complete system
is dependent on many factors outside the control of
the generator set manufacturer. To avoid possible
safety hazards, make all mechanical and electrical
connections to the generator set exactly as specified in this manual. All systems external to the generator (fuel, exhaust, electrical, etc.) must comply
with all applicable codes. Make certain all required
inspections and tests have been completed and all
code requirements have been satisfied before certifying the installation is complete and ready for service.
Product Modifications
Agency certified products purchased from Cummins Power Generation comply only with those specific requirements and as noted on company product specification s heets. Subsequent modifications
must meet commonly accepted engineering practices and/or local and national codes and standards. Product modifications must be submitted to
the local authority having jurisdiction for approval.
FIGURE 1-1. TYPICAL GENSET -- RIGHT HAND VIEW
1-2
Page 9
2. Location and Mounting
Generator set installations must be engineered so
the generator set will function properly under the expected load conditions. Use these instructions as a
general guide only. Follow the instructions of the
consulting engineer when locating or installing any
components. The complete installation must comply with all local and state building codes, fire ordinances, and other applicable regulations.
Requirements to be considered prior to installation:
• Level mounting surface
• Adequate cooling air
• Adequate fresh induction air
• Discharge of generator set air
• Discharge of exhaust gases
• Non-combustible mounting surface
• Electrical connections
• Accessibility for operation and servicing
• Noise levels
• Vibration isolation
LOCATION
Generator set location is decided mainly by related
systems such as v entilation, wiring, fuel, and exhaust. The set should be located as near as possible to the main power service entrance. Exhaust
must not be able to enter or accumulate around inhabited areas.
Provide a location away from extreme ambient temperatures and protect the generator set from adverse weather conditions.
ACCESS TO SET AND LIGHTING
Generally, at least 1 meter (3 feet) of clearance
should be provided on all sides of the generator set
for maintenance and service access.
Lighting should be adequate for operation, maintenance and service operations and should be connected on the load side of the paralleling switchgear
so that it is available at all times.
LIFTING
See the generator set Operators Manual for lifting
details.
WARNING
INCORRECT INSTALLATION, SERVICE OR PARTS REPLACEMENT CAN RESULT IN SEVERE
PERSONAL INJURY, DEATH, AND/OR EQUIPMENT DAMAGE. SERVICE PERSONNEL MUST
BE TRAINED AND EXPERIENCED TO PERFORM ELECTRICAL AND MECHANICAL COMPONENT INSTALLATION.
IMPORTANT
DEPENDING ON LOCATION AND INTENDED USE, FEDERAL, STATE OR LOCAL LAWS AND
REGULATIONS MAY REQUIRE THAT YOU OBTAIN AN AIR QUALITY EMISSIONS PERMIT BEFORE BEGINNING INSTALLATION OF THE GENSET. MAKE SURE TO CONSULT LOCAL
POLLUTIONCONTROLANDAIRQUALITYAUTHORITIESBEFORECOMPLETING
CONSTRUCTION PLANS.
2-1
Page 10
MOUNTING
in harmful resonances and may void the genset
warranty.
The engine-generator assembly is mounted directly
to a skid-base. Vibration isolation between the skidbase and the supporting structure is always required. The use of unapproved isolators may result
Locate the vibration isolators (Figure 2-1) as shown
on the generator set Outline Drawing referenced in
the Data Sheet. Follow the manufacturers instructions for anchoring, assembly and leveling.
FIGURE 2-1. VIBRATION ISOLATORS
2-2
Page 11
FOUNDATION
The foundation to which the genset mounts is
equally as important as other parts of the installation. The foundation should provide a level, flat surface for the genset. Also, the foundation pad should
be isolated from the rest of the concrete flatwork
and the joint filled with a flexible caulking.
the foundation weight should be at least 75, 200
pounds. The density of concrete is approximately
0.084 lbs/in
3
. The depth of the foundation is calculated by dividing the weight by the density times the
area: 75,200 lbs
÷ (0.084 lbs/in
3
x 288 in. x 79 in) =
39 inches. Therefore, the foundation in this example
has a length of 288 inches, a width of 79 inches, and
a depth of 39inches.
Foundation size is determined by the dimensions
and weight of the equipment to be installed. The
length and width should be a minimum of 18 inches
longer and wider than the genset’s footprint. Length
and width of the genset are provided on the general
assembly drawings for each specific model.
The area for the genset’s foundation should be a
continuous surface with no significant interruptions
such as trenches for piping. Conduit stub--ups are
acceptable as long as their position does not interfere with the location of the genset mounting points.
The locations of the mounting points are shown on
the general assembly drawings for each specific
model.
The depth of the foundation is determined by the
weight of the equipment to be mounted on the
foundation. In order to provide sufficient strength
and vibration damping ability, the foundation should
be deep enough to make the weight of the founda tion equal to 1.5 times the weight of installed equipment.
For example, a 1750 GQPB Genset with a P80R
frame alternator is to be installed. The genset’s outline drawing gives this model’s dimensions as 270
inches long and 61 inches wide. By adding 18 inches to the length and width of the genset, the recommended foundation dimensions are 288 inches
long by 79 inches wide. The outline drawing also
provides a wet weight for the genset of approximately 50,130 pounds. Since the desired weight of
the foundation is 1.5 times the weight of the genset,
CHECKING ELEVATION OF SPRING
ISOLATOR LOCATIONS
In addition to proper size, the finish of the foundation must allow for proper mounting of the spring
isolators. The foundation area should be level and
flat within 0.25 inches. The spring isolators used to
mount the genset are for vibration isolation and to
provide movement of the genset during starting,
loading, and unloading. They are not to be used to
compensate for unlevel and uneven foundations.
After the foundation is installed but before the genset is in place, check the elevations of the spring isolator locations. The locations for each genset’s
spring isolators are provided by its general assembly drawing.
The elevation check is easily done using a transit
and sight rod. To check for level along the foundation length, the difference between the elevation of
the spring isolator locations at the front and rear of
the genset are compared. The difference between
the two locations should be 0.25 inches or less. To
check for level across the width of the foundation,
the elevation of the spring isolators at the front are
compared to each other, and the elevation of the
spring isolators at the back are compared to each
other. To check the flatness of the foundation, the
elevation of all spring isolator locations are
compared, and the difference between all locations
should be 0.25 inches or less. Refer to Figure 2-2 for
an example of the measurements of spring isolator
locations.
2-3
Page 12
DISTANCE FROM
ISOLATOR LOCATION
TO TRANSIT LINE
TRANSIT LEVEL SIGHT LINE
X4
ALTERNATOR
X1 -- 4 SPRING ISOLATOR LOCATIONS
FIGURE 2-2. MEASUREMENT OF SPRING ISOLATOR ELEVATIONS
Figure 2-2 represents typical spring isolator locations for one side of the genset. The measurements
at X1 and X4 are compared for level along the
length. The measurements at X1 for both sides are
compared, and the measurements at X4 for both
sides are compared to determine level across the
foundation width. The measurements at all locations for both sides are compared to determine flatness. The following measurements represent different situations.
A--BANKB--BANK
X1 = 48 INCHES
X2 = 48.25 INCHES
X3 = 48.125 INCHES
X4 = 48.25 INCHES
X1 = 48.25 INCHES
X2 = 48 INCHES
X3 = 48 INCHES
X4 = 48.125 INCHES
Based on the preceding measurements, the
foundation is level along the length of the A--Bank
within 0.25 inches, and the B--Bank is level within
0.125 inches. The foundation is level across the
width within 0.25 inches at the engine end and
0.125 at the alternator end. By comparing all mea-
X3
FOUNDATION
X2
ENGINE
XI
surements, the foundation is flat within 0.25 inches.
The conditions of this example, where the foundation is level and flat within specification, is uncommon. The following set of measurements are more
typical.
A--BANKB--BANK
X1 = 48.5 INCHES
X2 = 48.75 INCHES
X3 = 48.25 INCHES
X4 = 48.25 INCHES
X1 = 48.25 INCHES
X2 = 48.5 INCHES
X3 = 48.625 INCHES
X4 = 48 INCHES
Based on the preceding measurements, the
foundation is level along the length and width within
specification. However, a comparison of all the
measurement locations shows that the foundation
is outside the specification for flatness. The measurements are graphed in Figure 2-3 to show the
profile of the foundation.
2-4
Page 13
DIFFERENCE FROM
HIGH POINt
0
-- 1 / 8
-- 1 / 4
FOUNDATION PROFILE
x1x2
x3x4
A--BANK
-- 3 / 8
-- 1 / 2
-- 5 / 8
-- 3 / 4
-- 7 / 8
ISOLATOR LOCATION
FIGURE 2-3. GRAPHICAL REPRESENTATION OF FOUNDATION PROFILE
In Figure 2-3, the values at the top of the graph represent the isolator locations, and the values on the
left side of the graph show the differences from the
elevation of the highest isolator location on the
foundation. By using a transit to measure elevations, the recorded value is the distance to the
foundation from a level line above the foundation.
When measured in this way, the numerically lowest
value represents the highest point on the foundation. In this example, X4 located on the B--Bank side
of the genset measures 48 inches, which is the lowest numerical elevation measurement and the highest point of the foundation profile. The difference of
all other locations from the highest point shows the
distance each point is below it. These values are
plotted to create the foundation profile. The graph
shows that four of the isolator locations exceed the
specification of 0.25 inches for flatness: A--Bank X1
and X2, and B--Bank X2 and X3. This is a situation
where isolator locations should be adjusted to be
within specification for level and flatness before the
genset is installed.
SHIMMING ISOLATORS
Isolator locations can be shimmed to meet the specification for level and flatness for foundations with
conditions similar to those in the preceding example. The simplest approach is to shim an isolator
B--BANK
location before the isolators and genset are in
place. The shims are placed under the isolator to
raise its elevation to equal the highest point.
Returning to the preceding example and graph, the
elevation of shim heights is easily determined. As
the highest elevation point, there is no shim required at spring isolator location X4 on the B--bank.
All of the other locations are shimmed to equal it.
Shim heights at these locations are:
A--BANKB--BANK
X1 = 1/2 INCH
X2 = 3/4 INCH
X3 = 1/4 INCH
X4 = 1/4 INCH
X1 = 1/4 INCH
X2 = 1/2 INCH
X3 = 5/8 INCH
X4 = 0 INCH
Some of the isolator locations in the example are
within the level and flatness specification, but as
long as shimming was necessary at certain locations, it requires minimal extra material and labor to
adjust all locations. It is critical when installing shims
to ensure that the size of the shim sufficiently covers
the footprint of the isolator in order to provide a uniform surface beneath the isolator to support the
weight it carries.
2-5
Page 14
ALIGNING ENGINE, GEAR BOX AND
GENERATOR
Proper alignment of the engine, gear box and generator is necessary to avoid premature wear and improper operation of the genset.
Consult an authorized Cummins representative for
assistance with alignment of the gearbox generator
sets.
2-6
Page 15
3. Mechanical Connections
Generator set mechanical system installation includes connecting fuel, exhaust, ventilation, cooling
and starting systems.
FUEL SYSTEM
Pages A-3 and A-4 illustrate typical factory available gas train kits and Page A-5 a typical installation.
WARNING
explosive and can cause severe personal injury
or death. Do not smoke if you smell gas or are
near fuel tanks or fuel-burning equipment or are
in an area sharing ventilation with such equipment. Keep flames, sparks, pilot lights, electrical arcs and arc-producing equipment and all
other sources of ignition well away. Keep a type
ABC fire extinguisher handy.
WARNING
cause gas leaks which can lead to fire and severe personal injury or death. Gas supply pressure must be adjusted to generator set Specifications by trained and experienced persons.
WARNING
quately ventilated space can lead to explosive
accumulations of gas. Venting of gas train components and generator set room ventilation
must be in accordance with local codes.
Gaseous-fuel supply system design, materials,
components, fabrication, assembly, installation,
testing, inspection, operation and maintenance
must comply with the applicable codes. See NFPA
Standards Nos. 37 and 54.
Cleanliness is of the upmost importance in a fuel
system. Make every effort to prevent the entrance of
moisture, dirt or contaminants of any kind. Inspect
and clean all pipework and fuel system components
prior to assembly.
Gaseous fuels are flammable and
High gas supply pressure can
Gaseous fuel leaks into an inade-
genset Data Sheet for fuel consumption. For lowpressure gas supply systems the pressure range is
5to7psi (34to48kPa). For high-pressure gas
supply systems the pressure droop from engine not
running to full load should not exceed 20 percent.
Note: The engine gas solenoid valve must be protected by a safety device to shut off gas flow in the
event of a catastrophic failure of an upstream gas
pressure regulator.
The high-pressure gas train (Page A-4) is such a
safety device.
The low-pressure gas train (Page A-3) is NOT such a
safety device. The installer must install a safety device upstream of the low-pressure gas train.
1. Bolt the flexible gas hose supplied in the gas
train kit directly to the engine gas solenoid
valve. Make sure the flange has a gasket and
that flange bolts are torqued to 37 lb-ft
(50 N-m). See Page A-5.
2. Bolt the gas train (Page A-3 or A-4) to the flexible hose using a flange gasket. Rigidly support
both flanges of the gas train. Up to 15 feet (4.5
meters) of piping built to suit and rigidly supported on both ends may be located between
the gas train and flexible hose (Page A-5).
Make sure all flanges have gaskets and that
flange bolts are torqued to 37 lb-ft (50 N-m).
The flanges between which the flexible hose is
bolted must line up and be spaced such that the
flexible hose fits without bending or being
stretched or compressed. Also, the flange on
the supply end must be rigidly supported to prevent engine vibration from causing resonance
in the gas train.
WARNING
Failure of the flexible gas hose
or gas train due to faulty installation can
lead to fire or explosion. The installation
must be in accordance with these instructions.
The gas supply system must be sized and regulated
to supply the generator set at full load. Refer to the
3. Weld the adapter pipe flange in the low-pressure gas train kit to the end of the supply piping.
3-1
Page 16
4. The gas solenoid valve on the engine must be
vented safely to the outside of the building
(Page A-4). A section of flexible gas vent hose
must be installed at the solenoid valve to take
up engine vibration. See the generator set Outline Drawing for the location of the vent port and
its fitting size. The pressure regulator in the
high-pressure gas train kit must also be vented
outside.
5. The pressure regulator in the gas train kit has
been preadjusted at the factory to maintain
200 millibar at the gas inlet to the engine. Measure the pressure at the engine inlet test port
and readjusted as necessary. The regulator
manufacturer’s instruction sheet is included in
the kit.
EXHAUST SYSTEM
See the Generator Set Data Sheet for exhaust temperature, flow and maximum back pressure.
WARNING
haust system must be leak-free and convey all
exhaust outside, away from windows, doors
and vents. Do not use exhaust gases to heat a
building or other enclosed space.
EXHAUST GAS IS DEADLY! The ex-
Flexible exhaust sections must not be used to compensate for misaligned piping or to form bends.
Avoid sharp bends by using sweeping, long radius
elbows and provide adequate support for mufflers
and piping.
Horizontal runs of exhaust piping should slope
downwards away from the engine to a drain trap
and plug, which should be located where the piping
turns to rise vertically.
To prevent overheating that can lead to fire, route
exhaust piping at least 12 inches (305 mm) away
from combustible construction. Use approved
thimbles where exhaust piping passes through
combustible walls, ceilings and roofs. Where the
minimum clearance cannot be maintained, piping
may be shielded or insulated with material rated to
withstand at least 1100°F (600°C). The surface of
the insulation or shield must not exceed 160°F
(71°C). Refer to Section 6-3 of NFPA 37, StationaryCombustion Engines and Gas Turbines for accepted design practices.
WARNING
Exhaust piping is very hot and can
ignite combustible material. Route, shield or insulate exhaust piping to protect adjacent combustible materials.
Exhaust Piping
The exhaust system must meet local codes.
Pipe all exhaust gases outside, away from windows, doors and vents. The exhaust system must
be gas tight. Exhaust gas must not be used to heat a
building or other enclosed space.
The exhaust system must be supported independently of the engine. Supporting the weight of exhaust piping on the turbocharger outlet flanges can
lead to turbocharger failure. Use the flanged flexible
bellows-type stainless steel tubes shipped with the
generator set for exhaust connections.
CAUTION
chargers, do not support any part of the exhaust
system on the turbocharger outlet flanges. Use
the flanged flexible exhaust tubes provided.
Long runs of exhaust pipe (vertical or horizontal)
should include sections of flexible, bellows-type
stainless steel tube to take up thermal expansion.
To prevent damage to the turbo-
WARNING
Exhaust piping, mufflers and boilers are very hot and can cause severe burns.
Shield or insulate exhaust piping and equipment where there is danger of personal contact.
The entire exhaust system must be accessible for
visual inspection and repair.
Use rain caps when exhaust pipes discharge vertically.
Exhaust Heat Recovery Boilers
For installations in the U. S. A., a heat recovery boiler must bear the appropriate ASME mark for fired
hot water pressure vessels and be equipped with
the appropriate pressure relief valve. The operating
system must include an approved high temperature
limit control.
WARNING
can cause severe personal injury or death. To
reduce the risk of explosion, boiler construction, pressure relief valves and safety controls
must meet all local codes and regulations.
A heat recovery boiler explosion
3-2
Page 17
VENTILATION
Generator set room ventilation must remove the
heat radiated to the ambient and make up the combustion air intake flow. See the Generator Set DataSheet.
Locate air inlet and outlet openings to minimize the
effects of wind and maximize convective air flow in
the generator room. Size ventilation fans, louvers,
and ducts so they are large enough to handle the re quired flow of air.
rates, maximum and minimum static heads and
maximum pressure drops (friction). Refer to the Operator’s Manual for recommended coolant mixtures.
Page A-6 illustrates schematically a recommended
coolant system configuration designed to provide
the following:
• Coolant system pressurization and balancing
between the HT and LT circuits
• Coolant Deaeration
Forced ventilation air flow should be directed parallel with the crankshaft and flow from rear (alternator
end) to the front of the engine.
The engine crankcase breather has specific routing
requirements as follows:
• The EcoVent exhaust hose inner diameter
must be greater or equal to 2.25 inches (EcoVent discharge diameter)
• The EcoVent exhaust must be vented to the atmosphere and never vented to the engine
room
• The EcoVent exhaust hose or pipe must be
monotonically rising
• The EcoVent exhaust hose or pipe should discharge a minimum of 10 feet from the engine
(room) air inlet, and preferably on the down
wind side of the inlet.
See Section 4. DC Connections for connections to
operate fans, louvers and dampers when the generator set is started and running.
• Volume for coolant thermal expansion
• Coolant pressure relief if bladder fails in the ex-
pansion tank
• Means to warn and shut down on low and high
coolant pressures
• Connection for draining coolant and filling from
the bottom by means of a pump
• Valves to isolate engine and heat exchangers
during service
• Mechanical gauges as backup and quick reference for pressure and temperature on dis charge and return loops of LT and HT circuits
(On a bladder tank system a single pressure
gauge is all that is needed.)
Note 1: A bladder tank is recommended for more
consistent system pressurization and balancing.
Automatic pressure balancing reduces crossflow
between the HT and LT coolant circuits.
Note 2: Static air vents should be placed at all the
high points in the system to eliminate air traps.
COOLANT SYSTEM
When designing the high temperature (HT) and low
temperature (LT) cooling systems, heat recovery,
radiator or other heat dump systems, refer to the
Generator Set Data Sheet for engine coolant volumes, maximum inlet and outlet temperatures, flow
Note 3: Follow t he pressure relief, initial bladder air
pressure, and low and high pressure switch settings
on Page A-6.
Note 4: The flexible coolant flange connectors provided with the generator set must be used for connection to the coolant piping system. All coolant piping must be Schedule 40 steel pipe.
3-3
Page 18
AIR STARTING (OPTIONAL)
See the Generator Set Data Sheet for air starting
system requirements. Figure 3-1 illustrates the air
starter connection.
WARNING
Accidental starting of the generator
set can cause severe personal injury or death.
To prevent accidental starting, do NOT connect
the air supply line until the installation has been
completed and the set is ready to be started.
1 INCH FLEX HOSE
GENSET START AIR SUPPLY-
CONNECTION POINT (1 INCH BSP)
FIGURE 3-1. AIR STARTER CONNECTION
3-4
Page 19
4. DC And Control Connections
Local regulations often require that wiring connections be made by a licensed electrician, and that the
installation be inspected and approved before operation. All connections, wire sizes, circuit protection, materials used, etc. must conform to the requirements of electrical codes in effect at the installation site.
WARNING
electrical hazard, resulting in severe personal
injury or death and/or property and equipment
damage.
Improper wiring can cause a fire or
GENERATOR CONTROL PANEL (GCP)
The Generator Control Panel (GCP) is a free standing module that includes the Power Command Supervisor (PCS) and Human Machine Interface
(HMI) and other customer interface features such
as an emergency stop switch, gas valve switch and
manual pre-lube push-button switch.
See page A-1 for an illustration of typical generator
set connections, including connections to the GCP.
There are two wiring harnesses that connect the
GCP to the Genset Interface Box (GIB), which is
mounted to the genset. The wiring harnesses are
supplied by the factory and come in various lengths
of 5, 10, 15, 20, 30, and 40 meters to accommodate
the customer’s location for the genset. Cable length
must be specified when the order for the genset is
placed.
CUSTOMER TERMINALS (GCP)
Customer connections to the genset are located in
the GCP on customer terminal block C (see Figure
4-1), and include: fault and alarm inputs, inputs and
outputs for genset and ancillary system control,
connections for paralleling functions, and additional
emergency stop inputs. See page A-2 for a list of
customer terminals and their functions. At time of
installation, check the current factory drawing for a
correct list.
The modbus plus tap for connection of network
communication lines is also located in the GCP.
The relay contacts for operating the remote control
and annunciating devices connected at the customer terminals are rated at 5A @ 250VAC, 30VDC.
B+ fused at 6 amps (5 amps UL) is available at the
customer terminals. See connection diagram on
page A-2 or equivalent for correct terminal numbers.
The terminal blocks in the GCP are suitable for a
maximum wire size o f 16 AWG (2.5 mm
Refer to Cummins 900-0366 PowerCommand Net-work Installation and Operation manual for the type/
gauge wire to use for network connections.
To accommodate the motion of the generator set on
its mounts, use flexible conduit and stranded conductors for all wiring that is routed to and terminates
in the GIB. See page A-1.
CAUTION
ator set movement and vibration can break solid copper wire.
CAUTION
separate conduits from AC power cables to
avoid inducing currents that could cause erratic
control.
Use stranded copper wiring. Gener-
Always run control circuit wiring in
2
).
4-1
Page 20
HARNESS EA
FROM GEN-
SET
HARNESS EB
FROM GENSET
TERMINALS FOR EXTERNAL
CUSTOMER CONNECTIONS
MODBUS
PLUS TAP
0500--4407
FIGURE 4-1. CUSTOMER CONNECTIONS IN THE GENERATOR CONTROL PANEL (GCP)
4-2
Page 21
BATTERY STARTING SYSTEMS
See the Generator Set Data Sheet for s tarting battery requirements. Figure 4-2 illustrates the starting
battery cables and connections at the batteries for
24 volt starter supply.
WARNING
gases causing severe personal injury. Do not
smoke when servicing batteries. Always wear
safety glasses. To reduce sparking always turn
Sparks can ignite explosive battery
BATTERY CABLE CONNECTIONS AT STARTER
off AC power to the battery charger and disconnect the negative ( - ) cables first and reconnect
them last. Secure insulating boots over the positive (+) terminals at the batteries and starter.
WARNING
Accidental starting of the generator
set can cause severe personal injury or death.
To prevent accidental starting, do not connect
the negative ( - ) cables at the batteries until the
installation has been completed and the set is
ready to be started.
CONNECTIONS AT BATTERIES FOR
FIGURE 4-2. BATTERY CONNECTIONS
24 VOLTS AT STARTER
4-3
Page 22
Relocation of Starting Batteries
If the batteries are mounted at a distance that is further from the starter than the standard cables allow,
the c ables must be designed accordingly, so that
the total resistance (cables plus connections) do not
result in an excessive voltage drop between the bat tery and the starter motor. Total cranking c ircuit resistance, cables plus connections, must not exceed
0.002 ohms for 24 volt systems to meet engine recommendations.
connecting the batteries. There are six cable connections. See the following sample calculation.
1. Assume a resistance of 0.0002 ohms for the
starter solenoid contact (R
contact
).
2. Assume a resistance of 0.00001 ohms for each
of the six cable connections (R
connection
).
3. Based on the formula: Maximum Allowable
Cable Resistance = 0.002 -- R
R
contact
= 0.002 -- 0.0002 -- (6 x 0.00001) =
connection
--
0.00174 ohms.
A Calculation Example
A generator set’s starting system is 24 VDC powered by two 12 volt batteries connected in series.
The total cable length is 35 feet, including the cable
#1
#2
2
)(35 MM2)
(50 mm
0.0030
0.0025
0.0020
0.0015
0.0010
Resistance (ohms)
0.0005
(50 mm
#0
4. Refer to figure 4-3 for the American Wire
Gauge (AWG) or mm
2
cable resistances,
which shows by the dashed lines that the smallest usable cable size is two #00 cables in
parallel.
2
)
#00
(70 mm
2
)
#000
(70 mm2)
#0000 or 2 #0
(95 mm2OR 2--50 mm2)
2#00
2#000
(70 MM
2#0000
(95 MM
2
)
2
)
2
)
(70 MM
0.0000
50
(15.2)
(0)
0
10
(3.1)
20
(6.1)
Length of Cable in Feet (Meters)
30
(9.1)
40
(12.2)
FIGURE 4-3. RESISTANCE VS LENGTH FOR VARIOUS AWG (MM2) CABLE SIZES
4-4
Page 23
5. Auxiliary Equipment Connections
Local regulations often require that wiring connections be made by a licensed electrician, and that
the installation be inspected and approved before
operation. All connections, wire sizes, circuit
protection, materials used, etc. must conform to
the requirements of electrical codes in effect at
the installation site.
WARNING
or electrical hazard, resulting in severe personal injury or death and/or property and
equipment damage.
See Page A-1 for an illustration of typical generator set connections, including connections to the
generator set mounted Generator Interface Box
(GiB).
Auxiliary genset equipment such as engine coolant heaters, alternator heaters, oil priming pump,
etc., are prewired to the GIB. AC power must be
supplied to the GIB.
Two supplies are required for 60 Hz machines.
One supply is 480 volts, 3--phase with a capability
of 25 continuous amps. The other supply is 120
volts, single phase with a capacity of 25 continuous amps. The maximum cable size at termination for both circuits is 6 AWG (16 mm
maximum circuit breaker size of 50 amps. See
Figure 5-1.
Improper wiring can cause a fire
2
)witha
One supply is required for 50 Hz machines, a
single 380--440 volt, 3--phase supply with a capacity of 42 continuous amps. The maximum
cable size at termination is 6 AWG (16 mm
a maximum circuit breaker size of 50 amps. See
figure 5-2.
There is a single-phase supply with circuit breaker available in the GIB for customer use, which is
usually used to supply the PSU. See page 5-4
for more information about the PSU.
CAUTION
erator set movement and vibration can break
solid copper wire.
Use stranded copper wiring. Gen-
2
)with
STARTING BATTERY CHARGER
In most installations a battery charger will be
installed to maintain the charge on the starting batteries. Capacity and size are chosen based on site
conditions and may be powered by one of the c ustomer supplies from the GIB or by another supply.
The following rule of thumb may be useful to size the
charger:
Required Battery Charging Amps =
1.2 X Battery Amp Hours
Hours.
÷ Required Charging
5-1
Page 24
SUPPLY FOR
CUSTOMER USE
AUXILIARY SUPPLIES
CUSTOMER EARTH
POINT (EP)
110--120V
1PH/2 WIRE
500--4412
10A SUPPLY FOR CUSTOMER USE
110 -- 120V, 1PH/2 WIRE
(RECOMMENDED FOR PSU)
480V3PH/3
WIRE
AUXILIARY SUPPLY
CONNECTIONS
FIGURE 5-1. CUSTOMER CONNECTIONS IN THE GENSET INTERFACE BOX (GIB) FOR 60 HZ GENSETS
5-2
Page 25
FOR CUSTOMER USE
SUPPLY
AUXILIARY SUPPLY
CUSTOMER EARTH
POINT (EP)
10A SUPPLY FOR CUSTOMER USE
240V 1PH/2--WIRE
(RECOMMENDED FOR PSU)
380--440V 3PH/4--WIRE
AUXILIARY SUPPLY CONNECTION
500--4404
FIGURE 5-2. CUSTOMER CONNECTIONS IN THE GENERATOR INTERFACE BOX (GIB) FOR 50 HZ GENSETS
5-3
Page 26
POWER SUPPLY UNIT
The Power Supply Unit (PSU) is a loose component
enclosure that must be mounted as close as practical to the genset. The PSU supplies DC power for
the control systems of the genset. The PSU requires an AC supply and DC wiring to the genset’s
GIB. See figure 5-3.
The AC supply for 60 Hz gensets is single phase,
120V, and for 50 Hz gensets, the AC supply is single
phase, 220V. There is a 10 amp supply protected by
a circuit breaker that is available from the GIB, and it
is recommended that this supply be used to power
the PSU. Maximum wire size is 12 AWG (4 mm
2
DC wire length one way from the PSU to the GIB
should not exceed 40 feet (12 meters) and must be
8AWG(10mm
2
). If the cable length one way is less
than 25 feet (eight meters), the wire size can be reduced to 10 AWG (6 mm
CAUTION
GENERATOR SET MOVEMENT AND VIBRATION
CAN BREAK SOLID COPPER WIRE.
USE STRANDED COPPER WIRING.
2
).
).
5-4
Page 27
AUXILIARY
SUPPLY
DC CONNECTIONS
FIGURE 5-4. POWER SUPPLY (PSU) CUSTOMER CONNECTIONS
5-5
500--4409
Page 28
THIS PAGE LEFT INTENTIONALLY BLANK
5-6
Page 29
6. AC SUPPLY AND POWER Connections
Local regulations often require that wiring connections be made by a licensed electrician, and that the
installation be inspected and approved before operation. All connections, wire sizes, materials used,
etc. must conform to the requirements of electrical
codes in effect at the installation site.
WARNING
electrical hazard, resulting in severe personal
injury or death and/or property and equipment
damage.
This section provides the procedure that is used to
connect the AC electrical system of the genset.
Before making any AC electrical connections, make
certain the generator set cannot be accidentally
started. Move the RUN/OFF/AUTO switch on the
control panel to the OFF position.
If the generator set has the optional air starting system, close the air supply valve.
If the generator set has a battery starting system,
turn off or remove AC power from the battery charger and then remove the negative (-- ) battery cable
from the set starting battery.
WARNING
can cause severe personal injury or death. Arcing at battery terminals, light switch or other
equipment, flame, pilot lights and sparks can ignite battery gas. Do not smoke, or switch
trouble light ON or OFF near battery. Discharge
static electricity from body before touching batteries by first touching a grounded metal surface.
Improper wiring can cause a fire or
Ignition of explosive battery gases
WARNING
set can cause severe personal injury or death.
Prevent accidental starting by disconnecting
the negative (- ) cable from the battery terminal.
WARNING
this section should be done only by persons
trained and experienced in electrical maintenance. Improper procedures may result in property damage, bodily injury or death.
Connecting the genset AC electrical system involves:
• Load cable connection
• Flexible sections of cable and conduit
• Generator insulation check
Before starting the genset, check to make sure that
all electrical connections are secure, and that all
wiring is complete. Replace and secure any access
panels that have been removed during installation.
Check that the load cables from the genset are
properly connected.
WARNING
cause electrocution or property damage. Do not
connect to any building electrical system except through an approved device and after
building main switch is opened.
Accidental starting of the generator
Each of the operations described in
Backfeed to utility system can
AC WIRING
Generator Voltage Connections
The generator output voltage and maximum current
rating are specified on the generator set nameplate.
Line-to-neutral voltage is always the lower voltage
shown and line-to-line voltage is the higher rating.
Ventilate battery area before working on or near
battery—Wear goggles—Stop genset and disconnect charger before disconnecting battery
cables—Disconnect negative (- ) cable first and
reconnect last.
CAUTION
AC source before disconnecting battery cables.
Otherwise, disconnecting cables can result in
voltage spikes damaging to DC control circuits
of the set.
Disconnect battery charger from
The generator is connected at the factory to produce a specified voltage per customer order (they
cannot be reconfigured for different voltages in the
field). Before shipping, the factory tests the generator set at the specified voltage.
See Page A-1.
Load Connections
Load connections are usually made from the generator output terminals to a free standing circuit break-
6-1
Page 30
er in an enclosure or to paralleling switchgear.
These cables are usually protected by conduit or a
raceway. There must be flexibility in the cables, con duits and/or wireway between the genset and surrounding structure. This flexibility is required to absorb the normal vibration movements of the genset.
Make sure that the cables and flex conduit are not in
a straight line from the genset output box to, for example, conduit in a concrete floor. Straight runs do
not provide three dimensions of flexibility. Always
designwithanoffset.
All loads are connected to the generator by lugging
the stranded load wires and bolting to the appropriate terminals on the generator reconnection terminal block. The terminals are stamped U, V, W and N
to indicate the line and neutral connections. (Reference: U, V, and W correspond with L1, L2 and L3;
and N with L0 respectively).
Load Balancing
When operating in parallel to a utility grid, the generator set will supply balanced load current to the system. Any unbalance of loads will be taken up by the
utility grid.
If the generator set is ever operated in Island Mode,
the loads should be balanced as closely as possible
across the three phases. When connecting loads to
the generator set, balance the loads so the current
flow from each line terminal (L1, L2 and L3) is about
the same. This is especially important if both single
phase and three phase loads are connected. Any
combination of single phase and three phase loading can be used as long as each line current is about
the same, within 10 percent of median value and no
line current exceeds the nameplate rating of the
generator. Check the current flow from each line after connections by observing the control panel ammeter.
6-2
Page 31
Grounding
Natural gas powered lean burn design generator
sets are usually connected through the use of paralleling switchgear. Some gensets will have a disconnect circuit breaker on its output in a free standing
enclosure. In any case there are many configurations and sequences of operation that may affect
how the genset neutral and the overall system is
grounded. If ground fault sensing equipment is included in the scheme, another element for consideration is added. The grounding decision must be
carefully considered by the system designer in consideration of system requirements, operational
needs, and local codes and standards in force at the
site.
Generally in a single genset system, the genset is
connected to the system loads using either three-wire or four--wire systems. In three--wire systems,
the neutral of the generator is not used (or not present in the case of delta systems). A neutral conductor is not installed from the genset to the switchgear
and to the loads. The power switching equipment is
therefore 3--pole. In this case the generator neutral
may be ungrounded, solidly grounded or resistance
grounded. See Figure 6-1 for a simplified diagram
showing this configuration. In four--wire systems the
neutral conductor is run from the generator and the
grounding scheme depends on whether the power
switching is 3--pole or 4--pole.
If the neutral is solidly connected from the genset to
the service entrance and loads, and the neutral is
grounded at the service entrance, then the genset
neutral is grounded through that system ground. No
additional neutral ground should be present at the
genset (and is usually not allowed by code). This
ground at the service is present whether operating
the genset in parallel or in island mode. See the simplified diagram in Figure 6-1.
The grounding question becomes considerably
more complex in four--wires systems if neutral is
switched, which means 4--pole breakers are used.
There are no straight forward rules or guidance regarding the grounding scheme. Multiple issues will
affect the grounding decision such as multiple gensets operating in parallel, ground fault sensing requirements, island vs. utility parallel operation,
protection schemes, and of course, safety. In these
complex schemes, the grounding decision must be
carefully considered and defined physically and operationally by the system designer.
WARNING
personal injury or death. Bonding and grounding must be done properly. All metallic parts
that could become energized under abnormal
conditions must be properly grounded.
Typical requirements for bonding and grounding
are given in the National Electrical Code, Article
250. All connections, wire sizes, etc. must conform
to the requirements of the electrical codes in effect
at the installation site.
Electric current can cause severe
Equipment Grounding (Bonding)
All equipment metallic parts must be grounded to
earth or to the earth ground system of the facility.
This includes the generator set frame, the GCP enclosure, the PSU enclosure, and any other equipment associated with the generation system. This
bonding is important for safety to avoid the chance
of metallic components becoming energized. It is
also important in reduction or elimination of stray
electrical noise and pulses from static charge or
lightning. There is a genset bonding point located
and marked as such on the bedframe (skid).
6-3
Page 32
UTILITY
SOURCE
SERVICE
GENSET
PARALLELING CB
GENERATOR
SOURCE
N
G
SIMPLIFIED DRAWING,
ELEMENTS MISSING
FOR CLARITY
UTILITY
SOURCE
N
G
N
G
GENERATOR NEUTRAL MAY BE:
LOADS
SOLIDLY GROUNDED (SHOWN),
OR RESISTANCE GROUNDED
PARALLEL OPERATION, 3-- WIRE, 3--POLE SWITCHING
GENSET
SERVICE
N
G
PARALLELING CB
N
G
UNGROUNDED,
GENERATOR
SOURCE
N
G
SIMPLIFIED DRAWING,
ELEMENTS MISSING
FOR CLARITY
LOADS
GENERATOR NEUTRAL NOT GROUNDED
AT THE GENSET IF THERE IS ANOTHER SYS-
TEM GROUND
PARALLEL OPERATION, 4-- WIRE, 3--POLE SWITCHING
FIGURE 6-1. PARALLEL OPERATIONS FOR 3--WIRE AND 4--WIRE, 3--POLE SWITCHING
6-4
Page 33
INSULATION RESISTANCE (MEGGER) &
POLARIZATION INDEX (PI) TESTING
Megger and PI testing must be performed on all
medium voltage (601 through 15,000 volts) generator sets before initial start -up. PI testing for low voltage (less than 600 volts) generator sets is recommended by Cummins Power Generation.
These tests are used to verify that the windings are
dry before the generator set is operated and develops a base line for future test comparison.
Before these tests can be performed on medium
voltage generator sets, you must first perform the
generator grounding procedure.
Generator Set Grounding Procedure
Prior to performing service or inspection procedures that may expose personnel to conductors
normally energized with voltages greater than 600
volts, the following generator set grounding procedure must be followed.
DANGER
unless fully trained in medium voltage grounding procedures and have necessary safety
equipment. Severe injury or death due to high
voltage electrical shock may result.
1. Open, lock-out and tag-out all sources of power
to the immediate work area.
2. Disable the starting system of the generator
set:
A. Move the Run/Off/Auto switch to the Off
B. Disconnect the battery charger from its AC
C. Remove the negative battery cable from
Do not perform these procedures
position and wait for the controller to power
down (approximately 10 minutes).
source.
the battery.
D. Install a lockout device on the battery
cable end. (For engines equipped with an
air-powered starting system, close air
valve and install valve locking device.)
3. Put on high voltage gloves with leather protectors.
4. Using two pre-tested voltage detection devices
(of the proper rating), verify de-energized condition in the work area. (Retest voltage detection devices immediately after verification of
de-energized condition.)
5. Remove the metal cover from the generator
output box to gain access to generator load terminals.
6. Securely install the Grounding Cluster ground
clamp to a verified “grounded” conductor.
WARNING
severe personal injury or death. After DC
voltage from the test equipment has been
applied to the windings and ground, there
will be a definite static charge on the windings. Reconnect Grounding Cluster to remove static charge from the winding after
each generator test.
7. With the Grounding Cluster in place, you are
protected from static and/or induced charges
that may have been present in the generator
stator.
8. Leave grounds connected for at least one minute so static charge can dissipate. Remove
ground cluster and perform PI and/or any other
tests required on the stator winding. Reconnect
grounds if additional generator service is necessary.
9. When work on the generator set is complete,
remove the Grounding Cluster in the reverse
order of installation.
10. After getting clearance from all personnel involved in the lock-out/tag-out procedure, remove all lock-out devices in reverse order of
installation.
Hazardous voltage. Can cause
6-5
Page 34
Megger and PI Test
DANGER
volts, present special hazards of severe personal injury or death. Even after genset shutdown,
an electrical shock hazard may still exist,
caused by induced voltage within the generator
or cables. Service personnel must be welltrained/qualified to work with distribution voltages. (See Generator Set Grounding Procedures, Page 6-3.)
WARNING
(601 through 15,000 volts) generator sets must
be dry before the generator is operated. Failure
to make sure windings are dry before start-up
may result in catastrophic equipment failure,
severe personal injury or death.
Megger Test: The megger test consists of applying
voltage for up to one minute. The highest resistance
values shown in Table 6-1 should be obtained for a
new generator with dry windings. For a set that has
been in service, the resistance reading should not
be less than the lower value shown.
Medium-voltage, 601 to 15,000
The windings of medium-voltage
1. Perform the Generator Set Grounding Procedure in this section.
2. Open the control box door and remove connector 10 from the AVR module.
3. Disconnect the AC voltage sense leads from
the generator output terminals. The AC voltage
sense leads are marked 5, 6, 7 and 8.
4. If the RTD (resistance temperature detector)
option is installed, ground all s ix RTD temperature leads. Each RTD has three leads, one red
and two white leads. Total of 18 leads must be
grounded.
Main Stator:
1. Remove and separate the neutral leads of the
generator from the generator load terminal
marked “N”.
2. Connect the megger between one phase of the
stator and ground while grounding the other
two phases and conduct the test. Refer to Table
6-1 for megger voltage selection and required
resistance values.
PI Test: The PI test consists of applying a voltage
between the winding and ground for ten minutes
and recording resistance values at one minute and
at ten minutes. The PI is the ratio of a ten minute
reading in megohms divided by a one minute reading in megohms. A ratio of two or greater is considered good for new and in service sets.
If low readings are obtained, the cause should be investigated and corrected before the generator set is
returned to service. If moisture is determined to be
the cause of low test readings, a winding drying process will be required (refer to genset Service manual for drying procedure).
3. Repeat this step in turn for the other two
phases.
Main Rotor:
1. Disconnect the main rotor and voltage suppressor leads from terminals F1+ and F2-- on
the rotating rectifier assemblies and isolate
them from ground. Tag and mark each lead
with its terminal number (F1+ or F2--).
2. Connect the megger between one of the rotor
leads and ground and conduct the test. Refer
to Table 6-1 for megger voltage selection and
required resistance values.
6-6
Page 35
FRAME
SIZE
P7
P80
P80
P80
GENERATOR
VO LTAGE
600 VAC or
less
600 VAC or
less
601 thru 5000
VAC
5001 thru
15000 VAC
TABLE 6-1. GENERATOR INSULATION RESISTANCE
MEGGER
VDC
SETTING
50010 -- 110 -- 110 -- 110 -- 1
100010 -- 5
500
2500100 -- 50
500
5000300 -- 150
500
MAIN
STATOR
MINIMUM RESISTANCE (MEG)
MAIN ROTORPMG
200 -- 100
(Combined rotors)
200 -- 100
(Combined rotors)
200 -- 100
(Combined rotors)
5--310 -- 5
5--310 -- 5
5--310 -- 5
EXCITER
STATOR
6-7
Page 36
THIS PAGE LEFT INTENTIONALLY BLANK
6-8
Page 37
7. Prestart Preparations
PRESTART PREPARATIONS
Initial startup and preparation for commissioning
may be performed only by a factory trained person
who is qualified for commissioning of lean burn natural gas gensets from Cummins Power Generation.
This work is normally performed in conjunction with
the commissioning of the switchgear as well as other site equipment.
CAUTION
of the control can cause equipment malfunction
or damage. Calibration and adjustment must be
performed by technically qualified personnel
only.
Assuring that the site is prepared for commissioning
will reduce time, mitigate issues, and assure efficient, effective commissioning efforts.
A generator set installation/prestart--up checklist is
included in this chapter and is useful to help assure
the site is ready. Qualified site personnel, or those
responsible for the design/installation, can use this
checklist during design and construction as well as
precommissioning to check many aspects of the
site.
A list of control and protection settings is also included in this chapter which provides descriptions
and factory settings. If other settings are desired by
qualified site personnel, a list of prepared setting
prior to commissioning can be prepared to clarify
and speed the process of setup of the control systems.
Improper calibration or adjustment
ELECTRICAL SYSTEM
Make sure all electrical connections are secure and
all wiring is complete and inspected. Replace and
secure any access panels that may have been removed during installation.
Battery Connections
WARNING
set can cause severe personal injury or death.
Make sure that the Run/Off/Auto switch on the
control panel is set to the Off position before
connecting the battery cables.
Starting the unit requires 24 volt battery current (see
Specification section). Connect 12 volt batteries in
series (negative post of first battery to the positive
post of the second battery).
Necessary battery cables are on the unit. Service
batteries as necessary. Infrequent use (as in emergency standby service), may allow battery to selfdischarge to the point where it cannot start the unit.
If installing an automatic transfer switch that has no
built-in charge circuit, connect a separate trickle
charger. Cummins Power Generation automatic
transfer switches include such a battery charging
circuit.
WARNING
can cause severe personal injury or death. Always connect negative ( - ) battery cable last to
prevent arcing.
WARNING
ing on or near battery. Arcing at battery terminals, light switch or other equipment, flame, pi lot lights and sparks can ignite battery gas. Do
not smoke, or switch trouble light ON or OFF
near battery. Discharge static electricity from
body before touching batteries by first touching
a grounded metal surface.
Accidental starting of the generator
Ignition of explosive battery gases
Ventilate battery area before work-
7-1
Page 38
GENERATOR SET INSTALLATION/
PRE--COMMISSIONING CHECKLIST
Room general and safety checks
Ensure starting is inhibited until ready
Lean burn gas generator set
This checklist should be used to validate the
completion of a generator set installation prior to
commissioning. A checklist should be completed for
each generator set of a multiple installation.
Project Details
Project Name:
Customer (End User):
Address of Site:
Telephone No.:
Email:
Start up date:
Generator set details
Generator set model:
Generator set serial number:
Generator set number:
Control type:
Warn personnel of impending equipment start-up
Generator set clean with all guards in place
No loose materials near generator set
Air ducts clear and clean
Access and egress routes unobstructed and labelled
Control and maintenance positions unobstructed
Room secure--no unauthorized access
Generator set is level-holding down bolts secure
Pipework and cables are secure with trip hazards
Overhead obstructions clearly marked and labelled
All key components are labelled
Pipework and services color coded and labelled
Electrical bonding complete
Cooling System
Remote mounted radiator systems
Header tank is adequately sized
Control serial number:
System control type (if applicable):
Generator set building and services
Building and installation work complete
Site clean and access clear from obstruction
Building services complete and commissioned
(lightning, lighting, electrical auxiliary supplies,
water, etc.)