Cummins Power Generation PowerCommand 3100 Series, DFHC, DFHD, DFHA, DFHB Installation Manual

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Installation Manual

PowerCommand Control

3100 Series

Generator Sets

Printed in U.S.A.

Models

DFHA, DFHB, DFHC, DFHD

960-0617E 10-2002

Table of Contents

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by any means, is strictly prohibited.

SECTION TITLE PAGE

IMPORTANT SAFETY INSTRUCTIONS iii. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1 INTRODUCTION

About this Manual 1-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Installation Overview 1-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 SPECIFICATIONS 2-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 MOUNTING THE GENERATOR SET

General 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Location 3-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mounting 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Access to Set 3-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Vibration Isolators 3-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Aligning Generator with Engine

(750 kW Generator Sets and Larger) 3-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 MECHANICAL CONNECTIONS

General 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fuel System 4-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Exhaust System 4-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Ventilation and Cooling 4-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 DC CONTROL WIRING

Control Wiring 5-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TB1 Remote Monitor/Control Connections 5-1. . . . . . . . . . . . . . . . . . . . . . . . . .

Run Relays (K11, K12, K13) 5-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Alarm Relay (K14) 5-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RTD Relay (Optional) 5-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Thermistor Relay (Optional) 5-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Diesel engine exhaust and some of its constituents are known
to the State of California to cause cancer, birth defects, and
other reproductive harm.

California

Proposition 65 Warning

i

SECTION TITLE PAGE

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6 AC ELECTRICAL CONNECTIONS

General 6-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Insulation Resistance (Megger) & Polarization Index (PI) Testing 6-2. . . . . . .

Transfer Switch 6-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

AC Wiring 6-5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Control Heater (Optional) 6-7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Coolant Heater 6-8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Generator Heater 6-9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fuel Transfer Pump 6-10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Ground Fault Alarm Relay (Optional) 6-12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 PRESTART PREPARATION

General 7-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PCC Power On/Standby Mode 7-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Electrical System 7-3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

PCC Options Prestart Checks 7-4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Starting 7-6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8 INSTALLATION CHECKLIST

General 8-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Generator Set Support 8-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cooling Air Flow 8-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Diesel Fuel System 8-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Exhaust System 8-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

AC and DC Wiring 8-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Generator Set Prestart 8-2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9 WIRING DIAGRAMS

General 9-1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

ii

IMPORTANT SAFETY INSTRUCTIONS

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by any means, is strictly prohibited.

SAVE THESE INSTRUCTIONS – This manual contains
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 operation can be

achieved only if the equipment is properly operated
and maintained. Many accidents 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.

This symbol warns of immediate
hazards which will result in severe personal in­jury or death.

WARNING

This symbol refers to a hazard or un­safe practice which can result in severe person­al injury or death.

CAUTION

This symbol refers to a hazard or un­safe practice which can result in personal injury
or product or property damage.

FUEL AND FUMES ARE FLAMMABLE

Fire, explosion, and personal injury or death can result
from improper practices.

• DO NOT fill fuel tanks while engine is running, un-

less tanks are outside the engine compartment.
Fuel contact with hot engine or exhaust is a potential
fire hazard.

• DO NOT permit any flame, cigarette, pilot light,

spark, arcing equipment, or other ignition source
near the generator set or fuel tank.

• Fuel lines must be adequately secured and free of

leaks. Fuel connection at the engine should be
made with an approved flexible line. Do not use zinc
coated or copper fuel lines with diesel fuel.

• 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 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.

• Be sure the unit is well ventilated.

• Engine exhaust and some of its constituents are

known to the state of California to cause cancer,
birth defects, and other reproductive harm.

MOVING PARTS CAN CAUSE SEVERE
PERSONAL INJURY OR DEATH

•

Keep your hands, clothing, and jewelry away from
moving parts.

• Before starting work on the generator set, discon-

nect battery charger from its AC source, then dis­connect starting batteries, negative (–) cable first.
This will prevent accidental starting.

• Make sure that fasteners on the generator set are

secure. Tighten supports and clamps, keep guards
in position over fans, drive belts, etc.

• Do not wear loose clothing or jewelry in the vicinity of

moving parts, or while working on electrical equip­ment. Loose clothing and jewelry can become
caught in moving parts.

• If adjustment must be made while the unit is run-

ning, use extreme caution around hot manifolds,
moving parts, etc.

DO NOT OPERATE IN FLAMMABLE AND
EXPLOSIVE ENVIRONMENTS

Flammable vapor can cause an engine to overspeed and
become difficult to stop, resulting in possible fire, explo­sion, severe personal injury and death. Do not operate a
genset where a flammable vapor environment can be
created by fuel spill, leak, etc., unless the genset is
equipped with an automatic safety device to block the air
intake and stop the engine. The owners and operators of
the genset are solely responsible for operating the gen­set safely. Contact your authorized Cummins Power
Generation distributor for more information.

LS-14M

iii

ELECTRICAL SHOCK CAN CAUSE

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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 DIRECT-

LY 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 be done only by persons
trained and qualified to work on such devices. Im­proper use or procedures will result in severe per­sonal injury or death.

• 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.

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. NFP A No. 10).

• Make sure that rags are not left on or near the en-

gine.

• 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 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 oper-

ating 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

1. Introduction

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by any means, is strictly prohibited.

ABOUT THIS MANUAL

This manual covers models produced under the
Cummins
tion brand names.

This manual provides installation instructions for
the generator set models listed on the front cover.
This includes the following information:



/Onan and Cummins Power Genera-

Mounting Recommendations - for fastening
generator set to base and space requirements
for normal operation and service.

Mechanical Connections Electrical Con­nections - covers most aspects of the genera-

tor set 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.

Installation Checklist – reference checks
upon completion of installation.

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

fication

tion, refer to Application Manual T-030, ”Liquid
Cooled Generator Sets”.

and

Data Sheets

. For application informa-

Speci-

1-1

INSTALLATION OVERVIEW

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by any means, is strictly prohibited.

These installation recommendations apply to typi­cal 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.

Application and Installation

A standby power system must be carefully planned
and correctly installed for proper operation. This in­volves two essential elements: application and
installation.

Application (as it applies to generator set installa­tions) refers to the design of the complete standby
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 are
responsible for the design of the complete standby

system and for selecting the materials and products
required.

Installation refers to the actual set–up and assem­bly of the standby 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 standby system normally requires
the special skills of qualified electricians, plumbers,
sheetmetal workers, etc. to complete the various
segments of the installation. This is necessary so
all components are assembled using standard
methods and practices.

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.

Copyright2001 Cummins Power Generation. All rights reserved.
Cummins, Onan and PowerCommand are registered trademarks of Cummins Inc.

1-2

2. Specifications

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by any means, is strictly prohibited.

MODEL DFHA, DFHB DFHC DFHD

Cummins Diesel Series QST30
Generator kW Rating See Genset Nameplate for rating information.
Coolant Capacity

Engine and Radiator

104° F (40° C)
122° F (50° C)

Lubrication System

Oil Capacity with Filters
Oil Type*

Engine Fuel Connection

Inlet/Oultet Thread Size Refer to Generator Outline Drawing

Fuel Flow

Max. Fuel Inlet Pressure
Max. Fuel Inlet Restriction
Max. Fuel Return Restriction

Exhaust

Outlet Size
Max. Allowable Back Pressure

Electrical System

Starting Voltage
Battery

Group number
CCA (minimum)

Cold Soak @ 0° F (-18° C)

* Refer to Cummins engine

Operation and Maintenance Manual

10 PSI (69 kPa)

4 in. Hg. (13.5 kPa)

10 in. Hg. (33.8 kPa)

6 in. (152 mm) flange
41 in. H2O (10.2 kPa)

for lubricating oil recommendations/specifications.

53 Gal (201 L)
57 Gal (216 L)

35 Gal (132 L)

10 PSI (69 kPa)

4 in. Hg. (13.5 kPa)

20 in. Hg. (67.6 kPa)

6 in. (152 mm) flange

27 in. H2O (6.7 kPa)

24 Volts DC

Two, 12 Volt

8D

1400

MODEL DFHA DFHB DFHC DFHD

US gph (L/hr) 54.7 (207.3) 57.8 (219) 60.2 (228.2) 69.3 (262.6)

FUEL CONSUMPTION (STANDBY/FULL LOAD/60HZ)

2-1

THIS PAGE LEFT INTENTIONALLY BLANK

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2-2

3. Mounting the Generator Set

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GENERAL

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

• Non-combustible mounting surface.

• Discharge of exhaust gases

• Electrical connections

• Accessibility for operation and servicing

• Noise levels

• Vibration isolation

LOCATION

Generator set location is decided mainly by related
systems such as ventilation, 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.

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 Y O U R L O C ATION AND INTENDED USE, FEDERAL, STATE OR LOCAL LAWS
AND REGULATIONS MAY REQUIRE YOU TO OBTAIN AN AIR QUALITY EMISSIONS PERMIT
BEFORE BEGINNING INSTALLATION OF YOUR GENSET. BE SURE TO CONSULT LOCAL
POLLUTION CONTROL OR AIR QUALITY AUTHORITIES BEFORE COMPLETING YOUR
CONSTRUCTION PLANS.

3-1

MOUNTING

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Generator sets are mounted on a steel skid that pro­vides proper support. The engine-generator as­sembly is isolated from the skid frame by rubber
mounts that provide adequate vibration isolation for
normal installations. Where required by building
codes or special isolation needs, generator sets
may be mounted on rubber pads or mechanical
spring isolators. The use of unapproved isolators
may result in harmful resonances and may void the
genset warranty.

Mount the generator set on a substantial and level
base such as a concrete pad. A non-combustible
material must be used for the pad.

Use 5/8 inch or 16 mm anchored mounting bolts to
secure the vibration isolators to the base. Secure
the vibration isolators to the skid using flat or bevel
washer and hexagonal nut for each bolt (see Figure
3-1). The 1-1/2 x 6 inch pipe inserted over the
mounting bolts allows minor adjustment of the bolts
to align them to the holes in the subbase or vibration
isolator.

MOUNTING

BASE

SUBBASE OR

VIBRATION

ISOLATOR

FLANGE

HEX NUT

FLAT OR BEVEL

WASHER

1-1/2 x 6 INCH

PIPE

12 IN.

(305 mm)

CONCRETE

Locate the isolators as shown on the generator set

Outline Drawing

referenced in the

Data Sheet

.

ACCESS TO SET

Generally, at least 1 meter (3 feet) of clearance
should be provided on all sides of the generator set
for maintenance and service access. A raised
foundation or slab of 150 mm (6 inches) or more
above floor level will make servicing easier.

Lighting should be adequate for operation, mainte­nance and service operations and should be con­nected on the load side of the transfer switch so that
it is available at all times.

MOUNTING

BOLT

FIGURE 3-1. BOLT DIAGRAM

3-2

CONDENSATION

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DRAIN TRAP

AC POWER

WIRING

MUFFLER

THIMBLE

SWEEPING

ELBOW

FLEXIBLE

SECTION

DC CONTROL

WIRING

AIR IN

AIR OUTLET

DUCT

VIBRATION

ISOLATORS

(5 EACH SIDE)

CONCRETE BASE

IMPORTANT!

COOLING AIR INLET MUST BE AT
LEAST 1-1/2 TIMES LARGER THAN
RADIATOR DUCT OUTLET AREA
ON RADIATOR COOLED MODELS

FLOW OF COOLING AIR AND
HEATED AIR CAN BE CONTROLLED
BY AUTOMATICALLY OPERATED
LOUVRES

FIGURE 3-2. TYPICAL INSTALLATION

3-3

VIBRATION ISOLATORS

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Installation and Adjustment Procedure

1. Place the vibration isolators (Figure 3-3) on the
genset support structure. The isolators should
be shimmed or grouted to ensure that all of the
isolator bases are within 0.25 inch (6 mm)
elevation of each other. The surface that the
isolator bases rest on must also be flat and lev­el.

2. Loosen the side snubber lock nuts so that the
top plate of the isolator is free to move vertically
and horizontally. Be sure that the top plate is
correctly aligned with the base and springs.

3. Place the genset onto the isolators while align­ing the skid’s mounting with the threaded isola­tor hole. The top plates will move down and ap­proach the base of the isolator as load is ap­plied.

4. Once the genset is in position, the isolators
may require adjusting so that the set is level.

The isolators are adjusted by inserting the lev­eling bolt through the skid and into the isolator
(the leveling bolt’s locking nut should be
threaded up towards the bolt head).

The leveling bolt will adjust the clearance be­tween the top plate and the isolator base. A
nominal clearance of 0.25 inch (6 mm) or great­er is desired. This will provide sufficient clear­ance for the rocking that occurs during startup
and shutdown. If the 0.25 inch (6 mm) clear­ance is not present, turn the leveling bolt until
the desired clearance is achieved.

5. The genset may not be level yet; therefore, ad­just the leveling bolts until the set is level and
sufficient clearance still remains. (Clearance
on all isolators should be roughly equal). Once
all isolators have been set, lock the leveling bolt
in place with the lock nut.

6. The snubber nuts may remain loose and there­fore provide better isolation between the gen­set and support structure.

GENSET SKID

LEVELING BOLT

LOCK NUT

CLEARANCE

SNUBBER

BASE

FIGURE 3-3. VIBRATION ISOLATORS

3-4

ALIGNING GENERATOR WITH ENGINE

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(750 kW GENSETS AND LARGER)

Proper alignment of the generator and engine as­semblies is necessary to avoid premature wear and
improper operation of the genset. Review the fol­lowing alignment conditions and procedures for
aligning the generator assembly to engine flywheel
housing.

Angular Misalignment

Angular misalignment is the result of the generator
bearing center axis not aligning with axis of the en­gine crankshaft. This condition creates an angle
between the generator shaft axis and the crank­shaft axis . The cause of this type of misalignment is
usually shimming error.

Axial Misalignment

Axial misalignment is the result of the generator
shaft axis not aligning with engine crankshaft axis.
The tolerances in the bolted flywheel and drive disc
connection may add up to displace the generator
axially relative to the crankshaft axis.

Misalignment Symptoms

If the assembly is allowed to run under these condi­tions, the discs must flex in alternate directions
twice for each engine revolution. It is important to
minimize the amount of disc flexing since, if it is ex­cessive, the drive disc will crack. Although perfect
bearing alignment is desirable, it is more important
to keep disc deflection to the very minimum pos­sible. This procedure assumes that the pilot bore of
the drive discs are in the exact center and the fly­wheel counterbore (pilot) has no practical runout.
Under these conditions, perfect Angular alignment
will be attained when no deflection of the discs is
measured.

Excessive Axial alignment will cause more genera­tor vibration than Angular misalignment.

Axial misalignment needs to be checked only when
an objectionable vibration is present.

Either type off misalignment may be present in a
generator set assembly , with angular misalignment
being the most common problem. Angular align­ment may also be ef fected by set installation condi­tions and/or mishandling during shipping of the gen­set.

GENERATOR
AND ENGINE

CRANKSHAFT

CENTERLINE

SHIMS

SEE DETAIL A

CLAMP

MOUNTING BOLT

TO DISC

MEASUREMENT

FIGURE 3-4. ANGULAR ALIGNMENT MEASUREMENT

AXIAL

ALIGNMENT

DIAL INDICATOR

FLEX

DISCS

DETAIL A

3-5

Angular Alignment Procedure

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by any means, is strictly prohibited.

WARNING

set during this procedure presents the hazard
of severe personal injury or death. Make sure to
disconnect the negative (-) battery cable(s) be­fore beginning.

Accidental starting of the generator

-.015”.) The indicator is closer to the top and further
away at the bottom. This example indicates that the
generator bearing is high. Since the side readings
are equal, the generator is centered side to side. T o
lower the generator, remove equal shims from un­der both generator mounting feet. To approximate
the amount of shims to remove or add:

Fasten a dial indicator to either the generator shaft
or the cooling fan with the sensing point resting on
the capscrew head or the flat surface of the drive
disc at the bolt circle diameter, see Figure 3-4. Bar
the engine over in a clockwise rotation as viewed
from engine flywheel. Do not allow it to roll back on
compression at the end of the travel of each read­ing. It is unnecessary to zero the indicator since the
total indicator reading (T.I.R.) of the deflection mea­surement to the bolt heads is what is required. T.I.R.
will be the sum of the maximum positive and nega­tive dial indicator readings as the engine completes
one revolution.

CAUTION

Do not bar engine over by prying on
fan blade. This may damage the blade and result
in premature, sudden blade failure.

Sample Generator Runout Readings: When taking
the deflection readings described, make a diagram
similar to the example shown in Figure 3-5, with a
total indicator reading of .025”. (The highest posi­tive value of +.010” and the largest negative value of

1. Measure the distance between the center of
the generator shaft to the point the indicator is
measuring at. (For example; a SAE 18 Disc
coupling distance is 10.7”).

2. Measure the distance from the generator side
of the flex discs to the center of the generator
mounting bolt, refer to Figure 3-4. (For exam­ple; a HC6 Frame’s distance is 28.4”.)

3. Compare the distance measured in steps 1 and

2. (28.4” vs 10.7” or a 2.65 to 1 ratio.) Multiply
this ratio times one half the T.I.R. (In our exam­ple, .025” divided by 2 is .0125”. This, times

2.65 equals .033”. Therefore, remove .033” of
shims from under both mounting feet.)

In general, the T.I.R. should not be more than .001”
for each inch of radius (center of shaft to indicator
axis). If w e use our example of 10.7 inches, then the
maximum T.I.R. would be .011”. This would only re­quire a correction of .014” from the T.I.R. of .025”. (A
reading of +.002 at the top and –.009 at the bottom
would fall within the satisfactory range.)

FIGURE 3-5. ANGULAR ALIGNMENT MEASUREMENT READINGS (EXAMPLE)

–.004

–.010

+.010

MEASURED AT

BOLT CIRCLE

DIAMETER

–.015

–.015

3-6

+.010

–.002

10.7 IN.

–.010

Axial Alignment Procedure

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by any means, is strictly prohibited.

Axial misalignment needs to be checked only when
an objectionable vibration is present.

If excessive vibration remains after the angular
alignment, check for concentric alignment of the
generator shaft/engine crankshaft axis.

to the varying surface quality of the generator
shaft’s drive disc mounting hub.

The goal of the Axial alignment is to reduce the
vibration level of the genset while it is operating. A
small improvement in the T.I.R. runout may have
dramatic effects in the mechanically measured or
physically observed vibration levels.

Fasten dial indicator holding device to skid base,
engine block, or generator shell with a magnetic
base or clamp and position so the sensor point of in ­dicator rests on the generator shaft hub, see Figure
3-6. Bar the engine over in a clockwise rotation as
viewed from engine flywheel, through a couple of
rotations. Record indicator readings in eight equal­ly spaced points around the shaft diameter. This will
provide a T.I.R. for Axial shaft misalignment.

The maximum allowable T.I.R. runout is subjective,
the optimal T.I.R. for runout would be .000 inches,
however that may not be attainable. The recom­mendation of this procedure will be to reduce the
measured T.I.R. runout by one half. Specific out-of­tolerance runout levels are difficult to establish due

ANGULAR ALIGNMENT

To correct for an out-of-tolerance T.I.R. indication,
remove the capscrews connecting drive discs and
flywheel. Mark the drive discs and flywheel with re­spect to each other. Rotate either the engine or gen­erator so that drive discs holes are repositioned 180
degrees from their original location. Put the drive
discs capscrews back in and retorque. Recheck
shaft alignment as before. If shaft T.I.R. runout re­mains unchanged then discs should be rotated to
either 30, 60 or 90 degrees from original location to
correct the out-of-tolerance condition. If the T.I.R.
does not improve after repositioning, a closer in­spection of the flywheel pilot and drive disc runouts
is required. This will help determine the cause of the
Axial misalignment.

SEE DETAIL A

GENERATOR
AND ENGINE

CRANKSHAFT

CENTERLINE

GENERATOR

SHAFT

HUB

DIAL

INDICATOR

CLAMP

FAN HOUSING

DETAIL A

FIGURE 3-6. AXIAL ALIGNMENT MEASUREMENT

3-7

THIS PAGE LEFT INTENTIONALLY BLANK

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3-8

4. Mechanical Connections

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by any means, is strictly prohibited.

GENERAL

The generator set mechanical system installation
includes connecting the fuel, exhaust, ventilation
and cooling systems. Before starting any type of
fuel installation, all pertinent state and local codes
must be complied with and the installation must be
inspected before the unit is put in service.

FUEL SYSTEM

Cummins engines normally use ASTM No. 2 diesel
fuel. They will, however , operate on alternate diesel
fuels within the specifications shown in the Cum­mins engine

In all fuel system installations, cleanliness is of the
upmost importance. Make every effort to prevent
entrance of moisture, dirt or contaminants of any
kind into the fuel system. Clean all fuel system com­ponents before installing.

A fuel filter/strainer/water separator of 100-120 mesh
or equivalent (approximately 150 microns nominal)
must be fitted between either the main tank and day
tank or between the main tank and the engine.

Use only compatible metal fuel lines to avoid elec­trolysis when fuel lines must be buried. Buried fuel
lines must be protected from corrosion.

CAUTION

lines, fittings or fuel tanks. Condensation in the
tank and lines combines with the sulfur in diesel
fuel to produce sulfuric acid. The molecular
structure of the copper or galvanized lines or
tanks reacts with the acid and contaminates the
fuel.

An electric solenoid valve in the supply line is rec­ommended for all installations and required for in­door automatic or remote starting installations.
Connect the solenoid wires to the genset “Switched
B+” circuit to open the valve during generator set
operation.

Operation and Maintenance Manual.

Never use galvanized or copper fuel

must not contain a shutoff device. Engine damage
will occur if the engine is run with the return fuel lines
blocked or restricted.

CAUTION

Never install shutoff device in fuel
return line(s). If fuel return line(s) is blocked or
exceeds fuel restriction limit, engine damage
will occur.

Fuel Return Restriction (or Pressure) Limit: Fuel

return drain restriction (consisting of friction head
and static head) between the engine injector return
line connection and the fuel tank must not exceed
the limit stated in the

Specification

section.

Fuel Lines – Routing

A flexible fuel hose(s) or section of flexible fuel
hose(s) must be used between the engine’s fuel
system and fuel supply and return line(s) to protect
the fuel system from damage caused by vibration,
expansion and contraction. Flexible lines for con­necting between the engine and the stationary fuel
lines are supplied as standard equipment.

Installation of the fuel hose must be done according
to all applicable codes and standards, and installa­tion recommendations provided by the manufactur­er. The supplied flexible hose is approved by the
hose manufacture for use with the genset fuel type
and product application.

Support fuel lines to restrain movement and prevent
chaffing or contact with sharp edges, electrical wir­ing and hot exhaust parts.

WARNING

fuel, leading to severe personal injury or death.
Do not route fuel lines near electrical wiring or
hot exhaust parts.

Fuel lines must be routed and secured to maintain a
1/2 inch (12.7 mm) minimum clearance from electri­cal wiring and a 2 inch (51 mm) minimum clearance
from hot exhaust parts.

Sparks and hot surfaces can ignite

Separate fuel return lines to the day tank or supply
tank must be provided for each generator set in a
multiple-set installation to prevent the return lines of
idle sets from being pressurized. Fuel return lines

Engine Fuel Connections

Identification tags are attached to the fuel supply
line and fuel return line connections.

4-1

ENGINE

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by any means, is strictly prohibited.

FUEL

PUMP

DAY TANK

FUEL TRANSFER
PUMP ELECTRIC

MOTOR DRIVEN

SHUTOFF

VALVE

1 INCH

120 MESH FUEL

STRAINER

VENTED
FILL CAP

FLOAT

SWITCH

LARGER OVER-

FLOW LINE

BAFFLE

INJECTOR FUEL

RETURN LINE

CONNECT TO

AC OUTPUT

SUPPLY

LINE

FUEL TANK

All models require a fuel return
line from injectors to tank.

VENT LINE

FILL PIPE

FIGURE 4-1. TYPICAL FUEL SUPPLY INSTALLATION

Supply Tank

Locate the f uel tank as close as possible to the gen­erator set and within the restriction limitations of the
fuel pump.

Install a fuel tank that has sufficient capacity to sup­ply the genset operating continuously at full rated
load for the planned period of operation or power
outage. Refer to
data.

WARNING

hazards which can result in severe personal in­jury or death. Always use flexible tubing be­tween engine and fuel supply to avoid line fail­ure and leaks due to vibration. The fuel system
must meet applicable codes.

If the fuel inlet restriction exceeds the defined limit
due to the distance/customer-supplied plumbing
between the genset and the main fuel tank, a trans-

Data Sheet

for fuel consumption

Fuel leaks create fire and explosion

fer tank (referred to as a day tank) and auxiliary
pump will also be required. If an overhead main fuel
tank is installed, a transfer tank and float valve will
be required to prevent fuel head pressures from be­ing placed on the fuel system components.

For critical start applications, where generator sets
are paralleled or must satisfy emergency start-time
requirements, it is recommended that a fuel tank or
reservoir be located such that the lowest possible
fuel level is not less than 6 inches (150 mm) above
the fuel pump inlet. This will prevent air from accu­mulating in the fuel line while the set is in standby,
eliminating the period during startup when it has to
be purged.

Fuel Inlet Pressure/Restriction Limit:: Engine

performance and fuel system durability will be com­promised if the fuel inlet pressure or restriction limits
are not adhered to. Fuel inlet pressure or restriction
must not exceed the limits stated in the

section.

tion

Specifica-

4-2

Day Tank (If Used)

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by any means, is strictly prohibited.

Fuel day tanks are used when fuel inlet restriction
limits can not be met, or the supply tank is overhead
and presents problems of high fuel head pressure
for the fuel inlet and return lines.

Supply T ank Lower Than Engine:

lation, the day tank is installed near the generator
set, below the fuel injection system and within the
fuel inlet restriction limit. Install an auxiliary fuel
pump, to pump fuel from the supply tank to the day
tank. A float switch in the day tank controls opera­tion of the auxiliary fuel pump.

The supply tank top must be below the day tank top
to prevent siphoning from the fuel supply to the day
tank.

Provide a return line from the engine injection sys­tem return connection to the day tank. Plumb the re-

With this instal-

turn line to the bottom of day tank as shown in Fig­ure 4-1. Provide a day tank overflow line to the sup­ply tank in case the float switch fails to shut off the
fuel transfer pump.

WARNING

Spilled fuel presents the hazard of
fire or explosion which can result in severe per­sonal injury or death. Provide an overflow line
to the supply tank from the day tank.

Supply Tank Higher Than Engine:

Install the day
tank near the generator set, but below the fuel injec­tion system. Use fuel line at least as large as the fuel
pump inlet. The engine fuel return line must enter
the day tank.

Include a shutoff valve in the fuel line between the
fuel supply tank and the day tank to stop fuel flow
when the generator set is off.

WARNING

Spilled fuel can create environmental hazards. Check local requirements for containment

and prevention of draining to sewer and ground water.

4-3

EXHAUST SYSTEM

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by any means, is strictly prohibited.

Pipe exhaust gases to the outside of any enclosure.
Locate the exhaust outlets away from any air inlets
to avoid gases re-entering the enclosure. Exhaust
installations are subject to various detrimental con­ditions such as extreme heat, infrequent operation
and light loads. Regularly inspect the exhaust sys­tem both visually and audibly to see that the entire
system remains fume tight and safe for operation.

WARNING

sult in severe personal injury or death. Use ex­treme care during installation to provide a tight
exhaust system. Terminate exhaust pipe away
from enclosed or sheltered areas, windows,
doors and vents.

For indoor installation, the exhaust system must
use sealed joint type fittings, (for example NPT fit­tings) to provide a tighter exhaust system. Use of
slip type fittings (secured with a muffler clamp) may
allow leakage of exhaust gases into the building.

WARNING

sult in severe personal injury or death. Use ex­treme care during installation to provide a tight
exhaust system. Use NPT or equivalent type fit­tings for all indoor installations.

Use an approved thimble (Figure 4-2) where ex­haust pipes pass through wall or partitions. Insu­lated wall/roof thimbles are used where exhaust
pipes pass through a combustible roof or wall. This
includes structures, such as wood framing or insu­lated steel decking, etc. Uninsulated wall/roof
thimbles are used where exhaust pipes pass
through a non-combustible wall or roof, such as
concrete. Refer to NFPA 37, Section 6-3. “Station­ary Combustion Engines and Gas Turbines” for ac-

Inhalation of exhaust gases can re-

Inhalation of exhaust gases can re-

cepted design practices. Build according to the
code requirements in effect at the installation site.

WARNING

Hot exhaust pipes can start a fire
and cause severe injury or death if improperly
routed through walls. Use an approved thimble
where exhaust pipes pass through walls or
partitions.

WARNING

Inhalation of exhaust gases can re­sult in severe personal injury or death. Do not
use exhaust heat to warm a room, compartment
or storage area.

Rain caps are available for the discharge end of ver­tical exhaust pipes. The rain cap clamps onto the
end of the pipe and opens due to exhaust discharge
force from the generator set. When the generator
set is stopped, the rain cap automatically closes,
protecting the exhaust system from rain, snow, etc.

Use a section of flexible exhaust pipe between the
engine and remainder of exhaust system. Support
exhaust system to prevent weight from being ap­plied to engine exhaust outlet elbow/turbocharger
connection.

CAUTION

Weight applied to the engine man­ifold can result in turbocharger damage. Sup­port the muffler and exhaust piping so no
weight or stress is applied to engine exhaust el ­bow.

The exhaust system design should meet local code
requirements.

Liability for injury, death, damage, and warranty ex­pense due to use of unapproved mufflers or modifi­cations becomes the responsibility of the person
installing the unapproved muffler or performing the
modification. Contact a Cummins Power Generation
distributor for approved exhaust system parts.

4-4

Avoid sharp bends by using sweeping, long radius

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by any means, is strictly prohibited.

elbows and provide adequate support for muffler
and tailpipe. Pitch a horizontal run of exhaust pipe
DOWNWARD (away from engine) to allow any
moisture condensation to drain away from the en­gine. If an exhaust pipe must be turned upward,
install a condensation trap at the point where the
rise begins (Figure 4-3).

Shield or insulate exhaust lines if there is danger of
personal contact. Allow at least 12 inches (305 mm)
of clearance if the pipes pass close to a combustible
wall or partition. Before installing insulation on ex­haust system components, check the exhaust sys­tem for leaks while operating the genset under full
load and correct all leaks.

RAIN CAP

9 INCH MIN

(230 mm)

VERTICAL

DRIP CAP

HOLES IN END

OF INNER

SLEEVE

ROOF

9 INCH MIN

(230 mm)

WARNING

Exhaust pipes are very hot and they
can cause severe personal injury or death from
direct contact or from fire hazard. Shield or in­sulate exhaust pipes if there is danger of per­sonal contact or when routed through walls or
near other combustible materials.

HORIZONTAL

WALL OR PARTITION

FIGURE 4-2. MOUNTING EXHAUST THIMBLE

IF EXHAUST LINE MUST BE

PITCHED UPWARD, CONSTRUCT

A TRAP AT POINT OF RISE

AVOID
SHARP
BENDS

DRAIN CONDENSATION

TRAP PERIODICALLY

FIGURE 4-3. CONDENSATION TRAP

4-5

VENTILATION AND COOLING

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by any means, is strictly prohibited.

Generator sets create considerable heat that must
be removed by proper ventilation. Outdoor installa­tions normally rely on natural air circulation but in­door installations need properly sized and posi­tioned vents for required airflow.

Vents and Ducts

For indoor installations, locate vents so incoming air
passes through the immediate area of the installa­tion before exhausting. Install the air outlet higher
than the air inlet to allow for convection air move­ment.

Size the vents and ducts so they are large enough to
allow the required flow rate of air . The ”free area” of
ducts must be as large as the exposed area of the
radiator. Refer to the genset
flow requirements and allowed airflow restriction.

Wind will restrict free airflow if it blows directly into
the air outlet vent. Locate the outlet vent so the ef­fects of wind are eliminated. See Figure 4-4.

Data Sheet

for the air-

PREVAILING WINDS PREVAILING WINDS

FIGURE 4-4. WIND BARRIER

4-6

Dampers

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by any means, is strictly prohibited.

Dampers or louvres protect the genset and equip­ment room from the outside environment. Their op­eration of opening and closing should be controlled
by operation of the genset.

In cooler climates movable or discharge dampers
are used. These dampers allow the air to be recircu­lated back to the equipment room. This enables the
equipment room to be heated while the genset en­gine is still cold, increasing the engine efficiency.

Radiator Set Requirements

Radiator set cooling air is drawn past the control
end of the set by a pusher fan that blows air through
the radiator (Figure 4-5). Locate the air inlet to the to
the rear of the set. Make the inlet vent opening 1-1/2
to 2 times larger than the radiator area.

Louvers and screens over air inlet and outlet open­ings restrict air flow and vary widely in performance.

A louver assembly with narrow vanes, for example,
tends to be more restrictive than one with wide
vanes. The effective open area specified by the lou­ver or screen manufacturer should be used.

Locate the cooling air outlet directly in front of the ra­diator and as close as possible. The outlet opening
must be at least as large as the radiator area.
Length and shape of the air outlet duct should offer
minimum restriction to airflow.

Attach a canvas or sheet metal duct to the flange
and the air outlet opening using screws and nuts so
duct can be removed for maintenance purposes.
The duct prevents circulation of heated air. Before
installing the duct, remove the radiator core guard.

Standard Radiator Cooling uses a set mounted
radiator and engine pusher fan to cool engine water
jacket. Air travels from the generator end of the set,
across the engine and out through the radiator. An
integral discharge duct adapter flange surrounds
the radiator grille.]

INLET AIR

DAMPER

COOL AIR

* Louvers should close when room
ambient is above 60

° F (16° C)

FIGURE 4-5. TYPICAL RADIATOR SET INSTALLATION

THERMOSTATIC AIR RE-

CIRCULATING DAMPER

*

RADIATOR FLEXIBLE DUCT

CONNECTOR

WIND/NOISE

BARRIER

HOT AIR

D

DISTANCE SHOULD NOT
BE LESS THAN HEIGHT

OF RADIATOR

4-7

Remote Radiator Cooling (Optional) substitutes

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by any means, is strictly prohibited.

a remote mounted radiator and an electrically driv­en fan in place of mounted components. Removal
of the radiator and the fan from the set reduces
noise levels without forcing dependence on a con­tinuous cooling water supply (necessary with heat
exchanger cooling). The remote radiator installa­tion must be completely protected against freezing.

Remote radiator plumbing will vary with installation.
Follow recommendations given in Application
Manual T-030. See product

Data Sheet

for friction

head and static head limits.

Before filling cooling system, check all hardware for
security. This includes hose clamps, capscrews, fit­tings and connections. Use flexible coolant lines
with heat exchanger or remote mounted radiator.

Engine Coolant Heater (Optional)

An optional coolant heater is available to keep the

engine warm for improved starting and code com­pliance. Connect the heater to a power source that
will be energized when the engine is NOT running.

Heat Exchanger (Optional)

The optional heat exchanger (Figure 4-6) uses a
shell and tube type heat exchanger instead of the
standard radiator and fan. Engine jacket coolant cir­culates through the shell side of the heat exchanger
while the cooling water is pumped through the
tubes. Engine coolant and raw water do not mix.

This system may reduce set enclosure airflow re­quirements and noise levels. Proper operation de­pends on a constant supply of raw water for heat re­moval. Adjust the flow to maintain engine coolant
temperature between165

° C) while viewing the water temperature gauge.

91
The engine coolant side of the system can be pro­tected from freezing; the raw water side cannot be
protected.

° F and 195° F (74° C and

COOL AIR

WATER

SOLENOID

VALVE

VENTILATING

FAN

WARM

AIR

FLEXIBLE WA-

TER

CONNECTIONS

MOUNTED HEAT

EXCHANGER

RAW WATER

SUPPLY

RAW WATER
DISCHARGE

FIGURE 4-6. TYPICAL HEAT EXCHANGER INSTALLATION

4-8

5. DC Control Wiring

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CONTROL WIRING

The generator set accessory box (Figure 5-1),
which is located on the backside of the control hous­ing, contains connection points for remote control
and monitor options.

CAUTION

Stranded copper wire must be used
for all customer connections to the Accessory
Box. Solid copper wire may break due to genset
vibration.

TB1 REMOTE MONITOR/CONTROL

CONNECTIONS

Customer monitor/control connections are at­tached to terminal block TB1 (Figure 5-1). Optional
equipment such as a remote annunciator panel,
sensing devices used to monitor genset operation,
remote start/stop switches, control box heater, bat­tery charger and etc. are attached to TB1. Refer to
PCC Customer Connections diagram in Section 9.

TB1 Wiring

CAUTION

a separate metal conduit from AC power cables
to avoid inducing currents that could cause
problems within the control.

Always run control circuit wiring in

Digital Connections: Connection points, other

then relayed outputs, network, switched B+ and B+
are considered digital connections to terminal strip
TB1. The type/gauge wire to use for these connec­tions are:

• Less than 1000 feet (305m), use 20 gauge

stranded copper wire.

• 1000 to 2000 feet (305 to 610m), use 18 gauge

stranded copper wire.

Relay Connections: Due to the wide variety of de­vices that can be attached to the relay outputs of
TB1, the electrical contractor must determine the
gauge of the stranded copper wire that is used at
this installation site. Refer to PCC Customer Con­nections diagram in Section 9 for the relay specifi­cations.

Network Connections: Refer to 900-0366

Command Network Installation and Operation

manual for the type/gauge wire to use for these con­nections.

Switched B+: (Fused at 10 amps.) Same as Relay
Connection description.

B+: (Fused at 20 amps.) Same as Relay Connec­tion description.

Power-

5-1

TB1-40

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TB1-1

OPTIONAL

COMMON ALARM

RELAY K14

OPTIONAL RUN RELAYS

K11, K12 & K13

OPTIONAL RTD

RELAY

GOVERNOR

OUTPUT MODULE

A38

PT/CT BOARD A36

FIGURE 5-1. ACCESSORY BOX COMPONENTS

OPTIONAL

THERMISTOR

RELAY 160/140

VOLTAGE

REGULATOR

OUTPUT MODULE

A37

° C

5-2

RUN RELAYS (K11, K12, K13)

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by any means, is strictly prohibited.

The optional run relays are rail mounted inside the
accessory box (Figure 5-1). The rail mount allows
you to easily remove and replace the snap-on re­lays. The generator set can be equipped with one,
two or three run relays.

The three-pole, double-throw run relays (Figure
5-2) are used to control auxiliary equipment such as

K11, K12, K13

fans, pumps and motorized air dampers. The run
relays are energized when the generator set control
receives a start signal.

The contacts are rated:

• 10 amps at 28 VDC or 120 VAC, 80%PF

• 6 amps at 240 VAC, 80%PF

• 3 amps at 480/600 VAC, 80%PF

A40-TB1-2

(SWITCHED B+)

K11, K12, K13

K11, K12, K13

K11

RUN RELAY

NO
NC

COIL

COM

A40-TB1-4

(B-)

CUSTOMER

CONNECTIONS

K12

RUN RELAY

NO
NC

K13

RUN RELAY

NO
NC

FIGURE 5-2. OPTIONAL RUN RELAYS (K11, K12, K13)

5-3

ALARM RELAY (K14)

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by any means, is strictly prohibited.

The optional alarm relay is rail mounted inside the
accessory box (Figure 5-1). The rail mount allows
you to easily remove and replace the snap-on relay.

The three-pole, double-throw alarm relay (Figure
5-3) is often used to energize warning devices such

K14

as audible alarms. Any generator set warning or
shutdown will energize the alarm relay.

The contacts are rated:

• 10 amps at 28 VDC or 120 VAC, 80%PF

• 6 amps at 240 VAC, 80%PF

• 3 amps at 480/600 VAC, 80%PF

A40-TB1-4

(GND)

A40-TB1-8

(COMMON ALARM)

K14

K14

JUMPER WIRE

REQUIRED FOR K14

RELAY OPTION

A40-TB1-1

(B+)

CUSTOMER

CONNECTIONS

K14

COMMON ALARM

NO
NC

COIL

COM

A40-TB1-7

(COMMON ALARM)

FIGURE 5-3. OPTIONAL ALARM RELAY (K14)

5-4

RTD RELAY (OPTIONAL)

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by any means, is strictly prohibited.

The optional RTD relay is rail mounted inside the
accessory box (Figure 5-1). This relay is used to
monitor six separate temperature zones in the gen­erator windings using resistive temperature detec­tors (R TDs). The relay determines the sensed tem­perature and acts to isolate, alarm, or initiate cor­rective action.

LED’s indicate the state of the output relay (green
for normal, red for tripped). Additional red LED’s are
used to indicate which inputs exceed the setpoint.

The relay terminals 1 1, 12 and 14 are for customer
connection. These terminals can be attached to any
one of the four Customer Fault inputs on TB1 to pro­vide a warning/shutdown condition or to other cus­tomer warning devices.

The RTD relay (Figure 5-4) compares the six inputs
to the predetermined setpoint (temperature set­point is factory adjusted). If one or more of the inputs
exceed the setpoint, the output relay is energized.

TEMPERATURE RELAY CONNECTIONS

The contacts are rated:

• 240 VAC, 5 amps non-inductive

• 24 VDC, 25 amps resistive

TO RTD TERMINAL

BLOCK

OUTPUT RELAY

(CUSTOMER USE)

(–)(+)

A40TB1-4

24 VDC

FIGURE 5-4. RTD RELAY (OPTIONAL)

(GROUND)
A40TB1-2

(SWITCHED B+)

5-5

TO RTD TERMINAL

BLOCK

THERMISTOR RELAY (OPTIONAL)

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by any means, is strictly prohibited.

(trip) when the thermistor chain resistance reaches
3000 ±500 ohms.

The optional thermistor relays are rail mounted in­side the accessory box (Figure 5-1). Each relay
monitors three thermistors (one per phase) that are
connected in series inside the generator. One se­ries or chain of thermistors are rated at 140
the other at 160

° C. The 140° C relay is commonly

° C and

used in a pre-alarm circuit. The relay will energize

THERMISTORS

BLUE

A∅ B∅ C∅

The relay terminals 1, 2 and 3 are for customer con­nection and are normally connected to a breaker
shunt trip or a load shed circuit (Figure 5-5).

The contacts are rated:

• 3 amps at 250 VAC

• 1 amp at 480 VAC

WHITE/RED

A40-TB1-4

(GROUND)

A40-TB1-2

(SWITCHED B+)

FAULT CHANNELS

(CUSTOMER

CONNECTIONS)

RELAY CONTACTS

FIGURE 5-5. THERMISTOR RELAY (OPTIONAL)

5-6

6. AC Electrical Connections

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by any means, is strictly prohibited.

GENERAL

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. T urn 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.

Ignition of explosive battery gases

WARNING

Each of the operations described in
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:

• Generator insulation check

• Installation of transfer switch

• Generator output voltage selection

• Load cable connection

• Standard and optional AC equipment connec-

tions (e.g., control box heater, coolant heater,
etc.

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.

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

Disconnect battery charger from AC
source before disconnecting battery cables.
Otherwise, disconnecting cables can result in
voltage spikes damaging to DC control circuits
of the set.

WARNING

Accidental starting of the generator
set can cause severe personal injury or death.
Prevent accidental starting by disconnecting
the negative (–) cable from the battery terminal.

WARNING

Improper wiring can cause a fire or
electrocution, resulting in severe personal inju­ry or death and/or property and equipment dam­age.

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

Backfeed to utility system can
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.

6-1

INSULATION RESISTANCE (MEGGER) &

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by any means, is strictly prohibited.

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.

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

Hazardous voltage. Can cause
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.

WARNING

No person should attempt to per­form these procedures unless they are fully
trained in medium voltage grounding proce­dures and have the necessary safety tools and
equipment. Persons who attempt these proce­dures without these qualification are at risk of
severe injury or death due to high voltage elec­trical shock.

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. Disconnect the battery charger from its AC

source.

b. Remove the negative battery cable from

the battery.

c. 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.)

7. With the Grounding Cluster in place, you are
protected from all static and/or induced
charges that may have been present in the
generator stator.

Leave grounds connected for one minute to in­sure static charge dissipation. Remove ground
cluster and perform PI and/or any other tests
required on the stator winding. Reconnect
grounds if additional generator service is nec­essary.

8. When work on the generator set is complete,
remove the Grounding Cluster in the reverse
order of installation.

9. After getting clearance from all personnel in­volved in the lock-out/tag-out procedure, re­move all lock-out devices in reverse order of
installation.

6-2

Megger and PI Test

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by any means, is strictly prohibited.

WARNING

volts, present special hazards of severe person­al injury or death. Even after genset shutdown,
an electrical shock hazard may exist. Service
personnel must be well trained and qualified to
work with distribution voltages.

WARNING

through 15,000 volts) generator sets must be
dry before the generator is operated. Failure to
ensure dry windings before start-up may result
in catastrophic failure, severe personal injury
and 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.

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, investigate the cause
and correct before the generator set is returned to
service.

1. Perform the

dure

Medium-voltage, 601 to 15,000

Windings of medium voltage (601

Generator Set Grounding Proce-

.

2. Disconnect plug J10 from the voltage regulator
output stage module and the AC control input
leads from the generator output terminals. The
AC control leads are marked 4, 5, 6, 7 and 8.
Refer to the reconnection diagram, which is lo­cated on the upper side cover of the control
housing.

3. If the RTD (resistive thermal device) option is
installed, ground all six resistive thermal device
temperature leads. Each RTD has three leads,
one red and two white leads. Total of 18 leads
must be grounded.

Main Stator:

4. Remove and separate the neutral leads of the
generator from the generator load terminal
marked “N”.

5. 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.

Repeat this step in turn for the other two
phases.

Main Rotor:

6. Disconnect the main rotor and voltage sup­pressor leads from terminals F1+ and F2– on
the rotating rectifier assemblies and isloate
them from ground. Tag and mark each lead
with its terminal number (F1+ or F2–).

7. 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.

GENERATOR VOLTAGE MEGGER VDC

600 VAC or less

601 thru 5000 VAC 2500 400 – 50

5001 thru 15000 VAC 5000 1000 – 200

TABLE 6-1. GENERATOR INSULATION RESISTANCE

MINIMUM RESISTANCE (MEG)

SETTING

500 5.0 – 1.0 5.0 – 1.0

1000

1000 5.0 – 1.0

MAIN STATOR MAIN ROTOR

6-3

5.0 – 1.0

TRANSFER SWITCH

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by any means, is strictly prohibited.

If the installation is for standby service, a transfer
switch must be used for switching the load from the
normal power source to the genset (see Figure 6-1).
Follow the installation instructions provided with the
transfer switch when connecting the load and con­trol wiring.

LOAD

NORMAL
SOURCE

FIGURE 6-1. TYPICAL LOAD TRANSFER

FUNCTION

GENSET

6-4

AC WIRING

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by any means, is strictly prohibited.

Generator Voltage Connections

The available generator output voltages and maxi­mum current ratings 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.

All loads are connected to the generator by bolting
stranded load wires to the appropriate terminals on
the generator reconnection terminal block or circuit
breaker lugs. 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

These generators can be configured to the name­plate voltages as shown on the Reconnection Dia­gram located on the side access cover of the control
housing. Many of the voltages listed will require re­configuration of the generator output leads on the
connection terminal block. This reconfiguration
must only be done by service personnel that are
trained and experienced to perform electrical instal­lation. The generator set was adjusted to produce a
specified voltage during production verification test­ing prior to shipment. The installer must always
check the stator lead terminal block connections
and perform any necessary reconnect to obtain the
voltage required.

Some generator sets are capable of producing a
wide range of voltages and connection configura­tions, others have specific limited capabilities. Re­fer to wiring diagram and generator voltages (from
the nameplate) when reviewing the voltage connec­tion information and use the wiring diagram sup­plied with your generator set when actually perform­ing load connections.

CAUTION

Reconfiguring generator sets to
higher voltages can exceed the voltage capabil­ity of the specific generator windings and dam­age the generator and also decrease line cur­rent, rendering line circuit breakers too large.
Consult with your distributor before performing
reconnection for a different voltage.

CAUTION

Reconfiguring generator sets to
lower voltages can reduce generator set rat­ings, and also increase line current, rendering
line circuit breakers too small. Consult with
your distributor before performing reconnec­tion for a different voltage.

Load Connections

Flexible conduit and stranded conductors must be
used for connections to take up movement of the
generator set.

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.

Current Transformers

Current transformers (CT’s) are required on gen­sets that contain AC meters. The CT’s must be
installed as noted in the following CT Installation
Requirements.

Refer to the Reconnection Diagram to identify the
output leads/phase that must be routed through
each CT, and also appropriate transformer post
selection for meter sensing leads. The transformers
are labeled CT21, CT22 and CT23 on the recon­nection wiring diagram. (The Reconnection Dia­gram is located on the upper side cover of the con­trol housing.)

CT Installation Requirements:

A. The CT has a dot on one side. This dot must be

facing toward the generator (conventional cur­rent flowing into the dot). A dot is also used to
indicate pin 1 of the CT.

B. CT21 – U load leads (A phase),

CT22 – V load leads (B phase)
CT23 – W load leads (C phase)

C. Route the appropriate load wires through each

CT.

D. The CT’s have dual secondaries (3 pins). The

CT secondary wire marked 1 is connected to
pin 1 of the CT. CT secondary wire marked 2/3
is connected to pin 2 for high voltage gensets or
to pin 3 for low voltage gensets. (Refer to Re­connection Diagram.)

6-5

Grounding

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by any means, is strictly prohibited.

The following is a brief description of system and
equipment grounding of permanently installed AC
generators within a facility wiring system. It is impor­tant to follow the requirements of the local electrical
code.

Figure 6-2 illustrates typical system grounding for a
3-pole and a 4-pole automatic transfer switch
(ATS). In the 3-pole ATS, note that the generator
neutral is connected to the ATS and is NOT bonded
to ground at the generator. In the 4-pole ATS sys­tem, a grounding electrode conductor and a bond­ing jumper are used to connect the generator neu­tral to ground. In some installations, a CT may be re­quired for ground fault monitoring (refer to Figure
6-2 for CT location).

3-POLE AUTOMATIC
TRANSFER SWITCH

3∅

TO UTILITY

SERVICE

N

Make sure the genset is grounded to earth in one
location only. On generators without a circuit break­er, ground to the point indicated on the top of the
generator. O n gensets with circuit breakers, use the
ground lug provided in the circuit breaker box.

WARNING

Electric current can cause severe
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.

GENERATOR SETSERVICE ENTRANCE

3∅
N

TO UTILITY

SERVICE

SERVICE ENTRANCE

FIGURE 6-2. TYPICAL SYSTEM GROUNDING ONE-LINE DIAGRAMS

4-POLE AUTOMATIC
TRANSFER SWITCH

4 WIRES & GROUND

TO LOAD

GENERATOR SET

4 WIRES & GROUND

TO LOAD

BONDING

JUMPER

CT LOCATION IF
REQUIRED FOR

GFI MONITORING

GROUNDING
ELECTRODE

CONDUCTOR

6-6

CONTROL HEATER (OPTIONAL)

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by any means, is strictly prohibited.

A control heater (Figure 6-3) provides a means of
humidity /temperature control of the control box in-

TO ACCESSORY BOX

A40–TB1-36 & 37

terior. I t protects the components when the genera­tor set is subjected to varying ambient air conditions
during extended periods of non-use.

HEATER

BOTTOM VIEW OF

CONTROL BOX

FIGURE 6-3. OPTIONAL CONTROL HEATER

6-7

COOLANT HEATER

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by any means, is strictly prohibited.

The coolant heater keeps engine coolant warm
when the engine is shut down. It heats and circu­lates the coolant within the engine. This reduces
startup time and lessens engine wear caused by
cold starts. It is electrically operated and thermo­statically controlled.

CAUTION

erated while the cooling system is empty or
damage to the heater will occur.

Figure 6-4 shows a typical coolant heater. Connect
the heater to a source of power that will be on during
the time the engine is not running. Be sure the sup-

The coolant heater must not be op-

ply voltage and circuit amperage is correct for the
heater element rating.

Refer to the Single/Dual Coolant Heater Diagram i n
Section 9 for coolant heater power connections/
voltage selections.

A battery charger is required to prevent battery dis­charge. The heater control relay draws 83 mA of cur­rent when the heater(s) is off. The heater is off when
the engine has reached the proper temperature or
the engine is running.

CAUTION

Do not connect AC power to the
heater before connecting battery cables. Heater
will run continuously without DC power and
can overheat and damage heater.

THERMOSTAT

COOLANT

FLOW

AC ELECTRICAL CONNECTION

BOX (ELECTRICAL DIAGRAM

INSIDE COVER)

DC SUPPLY

LINE

COOLANT

FLOW

DC CONTROL

LINE

DRAIN

AC POWER

LINE

FIGURE 6-4. TYPICAL COOLANT HEATER

6-8

GENERATOR HEATER

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by any means, is strictly prohibited.

A generator heater(s) is used to help keep the gen­erator free of condensation when the generator set
is not running. During cool and humid conditions,
condensation can form within a generator, creating
flashing and a shock hazard.

WARNING

tor increases the possibility of flashing and
electrical shock, which can cause equipment
damage and severe personal injury or death. Do
not use a generator which is not dry inside and
out.

Water or moisture inside a genera-

HEATER LEADS

Figure 6-5 illustrates the installation of two heater
elements. Connect the heater(s) terminals to a
source of power that will be on during the time the
engine is not running. Be sure the supply voltage
and circuit amperage is correct for the heater ele­ment rating.

HEATER

FIGURE 6-5. TYPICAL GENERATOR HEATER INSTALLATION

HEATER LEADS

HEATERS

TERMINAL BOX

HEATER

VOLT/WATTS

LABEL

TERMINAL

BLOCK

6-9

FUEL TRANSFER PUMP

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by any means, is strictly prohibited.

A fuel transfer pump and control are available when
a sub-base or in-skid day tank are provided. The au­tomatic control operates the fuel pump to maintain a
reservoir of fuel in the day tank.

WARNING

Diesel fuel is highly combustible.
Improper installation of this kit can lead to spill­age of large quantities of fuel and loss of life and
property if the fuel is accidentally ignited. Instal­lation and service must be performed by trained
and experienced persons in accordance with
the applicable codes.

Do not smoke near fuel and keep flames,
sparks, pilot lights, arcing switches and equip­ment, and other sources of ignition well away.

CONTROL

FLEXIBLE FUEL

RETURN LINE

FLEXIBLE FUEL

SUPPLY LINE

FUEL PUMP

AND MOTOR

FLOAT SWITCH

ASSEMBLY

FIGURE 6-6. TYPICAL IN-SKID DAY TANK INSTALLATION

DAY

TANK

FUEL

GAUGE

6-10

FUEL FILL

CAP

Fuel Pump Control AC Connections

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by any means, is strictly prohibited.

The control can be powered by 120 VAC or 240
VAC. The control is set up at the factory for connec­tion to 240 VAC.

1. To convert the day tank controller from 240
VAC to 120 VAC, perform the following steps.

A. Remove the two jumpers between termi-

nals TB1-6 and TB1-7 in the control box
and connect one between terminals
TB1-5 and TB1-6 and the other between
terminals TB1-7 and TB1-8.

2. To convert the day tank controller from 120
VAC to 240 VAC, perform the following steps.

A. Remove the jumpers between terminals

TB1-5 and TB1-6, and TB1-7 and TB1-8
in the control box and connect the two
jumpers between terminals TB1-6 and

TB1-7.

B. Move selector switch S103 on the control

PCB to the down position for 240 VAC.

C. If the control is equipped with a transform-

er, remove the jumpers between terminals
H1 and H3, and H2 and H4 and connect
the two jumpers between H2 and H3.

B. Move selector switch S103 on the control

PCB to the up position for 120V.

C. If the control is equipped with a transform-

er, remove the two jumpers between ter­minals H2 and H3 and connect one be-
tween H1 and H3 and the other between
H2 and H4.

3 Attach a tag to the control box indicating the

supply voltage.

4 Terminals TB1-8 and TB1-5 are available for

connection of a 120 or 240 VAC electric fuel
shutoff valve rated not more than 0.5 amps.
The voltage rating of the valve must corre­spond with the voltage utilized for the pump.
See Item 2 above.

FIGURE 6-7. FUEL PUMP CONTROL TERMINAL BOARD

6-11

GROUND FAULT ALARM RELAY

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by any means, is strictly prohibited.

(OPTIONAL)

The optional Ground Fault Relay (GFR) (Figure
6-8) is typically located behind the lower control
housing grille. The ground fault relay continuously
monitors the neutral to ground connection and acti­vates a fault alarm when the connection is broken.
During genset operation, the relay continuously
monitors the line to neutral and activates a fault
alarm when a ground fault is sensed.

After the installation of the genset is complete, per­form the following procedure to test the operation of
the ground fault relay.

A. Verify that the N-G Fault Indicator on the

GFR is not lit. If lit, it indicates that the
bonding jumper circuit (neutral to ground)
is open. If genset does not require bonding
jumper, a bonding jumper must be
installed at the facility service entrance.

The relay alarm contacts are typically connected to
the genset control to provide a “Ground Fault
Alarm” indication.

A control reset will clear the fault at the control panel
and will also reset the ground fault relay.

The relay has a time delay setting of zero to one
second and a current setting of 5 to 1200 amperes.

Adjust the Current and the Time Delay controls on
the ground fault relay to the customers specifica­tions.

A. Move the control switch to the Run posi-

tion.

B. Press the TEST switch on the ground fault

relay.

C. Verify that the control panel warning mes-

sage is displayed and the Fault Indicator
(>I) on the GFR is lit.

D. Reset the control panel fault (this will also

reset the ground fault relay).

6-12

CONTROL

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by any means, is strictly prohibited.

HOUSING

GROUND FAULT

RELAY

ASSEMBLY

GRILLE

TEST BUTTON

FAULT INDICATORS

> I

(OVER CURRENT)

N–G

(OPEN CIRCUIT)

FIGURE 6-8. GROUND FAULT ALARM RELAY

ON INDICATOR

RESET BUTTON

(N.U., FACTORY SET

TO AUTO RESET)

TIME DELAY CONTROL

CURRENT CONTROL

6-13

THIS PAGE LEFT INTENTIONALLY BLANK

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6-14

7. Prestart Preparation

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by any means, is strictly prohibited.

GENERAL

Before attempting the initial start of the generator
set, be sure to complete the

Section 9

.

Installation Checklist

in

PCC POWER ON / STANDBY MODE

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.

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.

Ignition of explosive battery gases

CAUTION

Disconnect battery charger from AC
source before disconnecting battery cables.
Otherwise, disconnecting cables can result in
voltage spikes damaging to DC control circuits
of the set.

WARNING

Accidental starting of the generator
set can cause severe personal injury or death.
Prevent accidental starting by disconnecting
the negative (–) cable from the battery terminal.

Before opening the PCC control cabinet to make
the following Power On/Standby Mode selection,
remove the negative (–) battery cable(s) from the
generator set starting battery as follows:

1. Move the Run/Off/Auto switch on the control
panel to the OFF position.

2. Turn off or remove AC power from the battery
charger.

3. Remove the negative (–) battery cable from the
generator set starting battery.

7-1

Selecting Power On or Standby Mode

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CAUTION

circuit boards. To prevent this damage, always
wear a grounding wrist strap when working in­side control box.

Set the Power On / Standby Mode switch (S5 in Fig­ure 7-1) to the desired position.

Power On Mode: Slide the switch to the left to se­lect the Power On (awake) mode. It is recom­mended that switch S5 be left in the Power On mode
in all applications, except those where battery
charging is not available.

The PCC will initialize the operating software and
permit operation of the menu display panel. Power
will stay on until the switch is reset to the Standby
Mode.

Standby Mode: Slide the switch to the right to se­lect the Standby (sleep) Mode. In this mode, the
PCC operating software will be initiated by:

Electrostatic discharge will damage

• moving the Run/Off/Auto switch to the Run

position,

• pressing the Self Test button,

• a remote start input signal (genset in Auto

mode), or

• any one of several “wake-up” signals from ex-

ternal switches.

With the switch set to Standby mode, pressing the
Self Test button will allow you to activate and view
the menu displays without starting the generator
set. If no menu selections are made, a software tim­er will shut down the power after 30 seconds.

When left in the Standby Mode, and a “Warning”
signal is sensed by the PCC (for example, low en­gine temp), the control will wake up and display the
warning message. The control will remain active
until the warning condition is corrected and the Re­set button is pressed to clear the warning message.

DISPLAY BOARD

(A35)

PCC POWER ON / STANDBY

MODE SWITCH (S5)

ANALOG BOARD

ENGINE INTERFACE

(A31)

DIGITAL BOARD

(A32)

(A33)

CUSTOMER INTERFACE

(A34)

FIGURE 7-1. CABINET INTERIOR (PCC 3100)

7-2

ELECTRICAL SYSTEM

Redistribution or publication of this document, 

by any means, is strictly prohibited.

Verify 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, us­ing two 12 volt batteries (see
Connect the batteries in series (negative post of first
battery to the positive post of the second battery) as
shown in Figure 7-2.

Accidental starting of the generator

Specification

section).

POSITIVE

NEGATIVE

Service the batteries as necessary. If an automatic
transfer switch is installed without a built-in charge
circuit, connect a separate battery charger. A bat­tery charger is required when the PowerCommand
control is set to the Power On (awake) mode.

WARNING

Ignition of explosive battery gases
can cause severe personal injury or death. Al­ways connect negative (–) battery cable last to
prevent arcing.

WARNING

Ventilate battery area before work­ing on or near battery. 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.

TWO, 12 VOLT

BATTERIES

FIGURE 7-2. GENERATOR SET BATTERY

CONNECTIONS

7-3

PCC OPTIONS PRESTART CHECKS

Redistribution or publication of this document, 

by any means, is strictly prohibited.

All generator set configuration options are set at the
factory except for site related options, (e.g., Start/
Stop Time Delays, Cycle Crank, Customer Fault 1
and 2, etc..

START DELAY submenu:

This delay applies only
to remote starting in the Auto mode. Use the buttons
next to the “

⇑” and “⇓” symbols to set the start delay .

The start delay adjustment range is 0 to 300 sec­onds.

Adjustment of these options are divided into two
categories within the menu driven system. These
two categories are

The

Setup/Calibrate

Adjust

and

Setup/Calibrate

submenus are intended for

.

qualified service personnel only and require a pass­word to modify these submenus. The

Adjust

sub­menus are intended for service personnel and site
personnel.

The

Adjust

submenus allow site personnel to cali­brate the generator set voltage/frequency, idle
speed and start/stop time delays. For the prestart
checks, adjustment of only the start/stop delays is
required.

Adjust Menu

To adjust the start and stop delays, press the button
next to the word “ADJUST” in the Main Menu. Fig­ure 7-3 shows a block representation of the AD­JUST menu. After you press the button next to the
word “ADJUST” in the display, the VOLTAGE sub­menu will appear.

STOP DELAY submenu:

This delay applies only
to remote stopping in the Auto mode. From the
START DELAY submenu, press the button next to
the “>>” in the display to move to the STOP DELAY
submenu. Use the buttons next to the “

⇑” and “⇓”

symbols to set the stop delay. The stop delay adjust­ment range is 0 to 600 seconds.

IDLE SPEED submenu:

From the STOP DELAY
submenu, press the button next to the “>>” in the
display to move to the IDLE SPEED submenu. Use
the buttons next to the “

⇑” and “⇓” symbols to set the

idle speed. The idle speed adjustment range is 800
RPM

±100 RPM. (Default value is 800 RPM.)

The idle speed can be adjusted only when the gener­ator set is running in the idle mode. When not in idle
mode, N/A is displayed in RPM field.

SAVE/EXIT submenu:

From the STOP DELAY
submenu, press the button next to the “>>” in the
display to move to the SAVE/EXIT submenu. Select
SAVE to save your changes. At the CHANGES
SAVED submenu, select EXIT to return to the Main
menu.

As shown in the diagram, the ADJUST menu has
five submenus, including a save/exit procedure. To
move through the VOLTAGE and FREQUENCY
submenus, press the button next to the ’>>’ to dis­play the STOP DELAY submenu.

If you select SAVE, the adjustments will be retained
after shutdown, and will be in effect when the set is
restarted. If you select EXIT without saving first, the
adjustments will remain in effect until the genset is
shut down and return to the previous settings when
the set is restarted.

7-4

ADJUST MENU

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by any means, is strictly prohibited.

<>

ENGINE GEN
ADJUST >>

<>

<

⇑ VOLTAGE

<>

⇓ _______ >>

<

⇑ FREQUENCY

<>

⇓ _______ >>

<

⇑ START DELAY

<>

⇓ _______ SEC >>

<

⇑ STOP DELAY

<>

⇓ _______SEC >>

⇑ IDLE SPEED

<

⇓ _______RPM >>

<>

<

SAVE
EXIT >>

<>

<

SAVE
EXIT >>

<>

<

SAVE
EXIT >>

<>

CHANGES SAVED
EXIT >>

<>

CHANGES SAVED
EXIT >>

<>

ENGINE GEN
ADJUST >>

<>

<

⇑ VOLTAGE

<>

⇓ _______ >>

<>

ENGINE GEN
ADJUST >>

<>

<

⇑ VOLTAGE

<><>

⇓ _______ >>

Indicates OR" Condition

FIGURE 7-3. ADJUST MENU

7-5

STARTING

Redistribution or publication of this document, 

by any means, is strictly prohibited.

Refer to the generator set

Operator’s

manual for im­portant safety precautions and recommended pro­cedures for starting the genset and verifying proper
operation. Start the generator set and verify all en­gine and generator gauges are displaying the cor­rect values.

7-6

8. Installation Checklist

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by any means, is strictly prohibited.

GENERAL

Generator set wattage capacity is sufficient to handle maximum anticipated load.



 At least 3 feet of clearance (or greater for housing door) is provided around entire generator set for servic-

ing and ventilation.

 Generator set is located in an area not subject to flooding.
 All operating personnel have read and are familiar with Operator’s Manual.
 All operators have been thoroughly briefed on preventive maintenance procedures.
 All operators have read and understand all Important Safety Instructions in Operator’s Manual.

GENERATOR SET SUPPORT



Floor, roof or earth on which the generator set rests is strong enough and will not allow shifting or move­ment. Observe local codes on soil bearing capacity due to freezing and thawing.

 Generator set is properly supported and retained to approved base.
 Supporting base is large enough and is of non-combustible material – extends 6-inches all around set.

COOLING AIR FLOW



Generator set air inlet is faced into direction of strongest, prevailing winds.

 Air inlet openings are unrestricted and at least 1–1/2 times larger than air outlet area.
 Cooling air outlet is on downwind side of building (if not, wind barrier is constructed).
 Proper ducting material (sheet metal, canvas) is used between radiator and air outlet.

DIESEL FUEL SYSTEM



Fuel tanks meet or exceed all Local, State or National codes.

 Fuel lines are properly installed, supported and protected against damage.
 Approved flexible fuel line is installed between main fuel supply line and generator set’s fuel system, near

the generator set, to protect the fuel system from damage caused by vibration, expansion and contrac­tion.

 Strainer or fuel screen (100 to 120 mesh) is installed in the fuel supply line to protect the fuel lift pump, day

tank transfer pump or float valve seat from fuel supply tank debris.

 Fuel supply line shutoff valves are installed to prevent fuel flow in case of leaks.
 No shutoff valves are installed on engine fuel return line.
 External fuel pumps are connected and operational at all times (generator set started or shut down).
 Fuel system is properly primed.
 No fuel leaks are found in supply line or engine fuel system.

8-1

EXHAUST SYSTEM

Redistribution or publication of this document, 

by any means, is strictly prohibited.

Operators are thoroughly briefed on the dangers of carbon monoxide gas.



 Areas around set are well ventilated. No possibility of exhaust fumes entering building doors, windows, or

intake fans.

 Exhaust gases are piped safely outside and away from building.
 The correct length of approved rigid pipe is connected to the generator set flexible pipe using approved

securing methods with no weight resting on engine exhaust components. There are no bends in flex sec­tion.

 Condensation drain is provided in lowest section of exhaust piping.
 Exhaust piping is insulated to guard against burns to personnel.
 Exhaust piping passing through walls or ceilings have approved fire-proof materials and are in com-

pliance with all codes.

 Exhaust piping is large enough in diameter to prevent excessive back pressure on engine.

AC AND DC WIRING

Wire sizes, insulation, conduits and connection methods all meet applicable codes.



 AC and DC wires are separated in their own conduit to prevent electrical induction.
 All load, line and generator connections are proper and correct.
 Flexible conduit between generator set and building or surrounding structure.

GENERATOR SET PRESTART

Generator set engine is properly serviced with oil and coolant.



 Batteries are properly installed, serviced and charged.
 Battery charger and engine coolant heater are connected and operational.
 All generator set covers and safety shields are installed properly.
 All fuel and coolant shutoff valves are operational.

8-2

9. Wiring Diagrams

Redistribution or publication of this document, 

by any means, is strictly prohibited.

GENERAL

This section consists of the schematic and connec­tion wiring diagrams referenced in the text. The fol­lowing drawings are included.

• Page 9-2 – Customer Connections Diagram

• Page 9-3 – Accessory Interconnect Diagram

• Page 9-4 – Single/Dual Coolant Heater Wiring

Diagram

9-1

THIS IS A REPRESENTATIVE (GENERIC)

Redistribution or publication of this document, 

by any means, is strictly prohibited.

SCHEMATIC/WIRING DIAGRAM. FOR
TROUBLESHOOTING, REFER TO THE
WIRING DIAGRAM PACKAGE THAT WAS
INCLUDED WITH YOUR GENSET.

No. 6126658 sh 3 of 3
Rev. D Sys: HP
Modified 8/13/97

PCC CUSTOMER CONNECTIONS

9-2

GENERATOR SET

Redistribution or publication of this document, 

by any means, is strictly prohibited.

WITH PCC CONTROL

OT AND BT 2 WIRE START

UTILITY TO GENSET

THIS IS A REPRESENTATIVE (GENERIC)
SCHEMATIC/WIRING DIAGRAM. FOR
TROUBLESHOOTING, REFER TO THE
WIRING DIAGRAM PACKAGE THAT WAS
INCLUDED WITH YOUR GENSET.

No. 6301345 sh 1
Rev. J
Modified 11/96

PCC ACCESSORY NTERCONNECT DIAGRAM

9-3

THIS IS A REPRESENTATIVE (GENERIC)

Redistribution or publication of this document, 

by any means, is strictly prohibited.

SCHEMATIC/WIRING DIAGRAM. FOR
TROUBLESHOOTING, REFER TO THE
WIRING DIAGRAM PACKAGE THAT WAS
INCLUDED WITH YOUR GENSET.

SINGLE COOLANT HEATER DIAGRAM DUAL COOLANT HEATER DIAGRAM

SINGLE/DUAL COOLANT HEATER DIAGRAMS

No. 5003104 sh 1 of 1
Rev. A
Modified 9/23/96

SINGLE/DUAL HEATER WIRING DIAGRAM

9-4

Cummins Power Generation

Redistribution or publication of this document, 

by any means, is strictly prohibited.

1400 73rd Avenue N.E.
Minneapolis, MN 55432
1-800-888-6626
763-574-5000 International Use
Fax: [phone]

Cummins is a registered trademark of Cummins Inc.