Guardian 5240 Operating instructions

MODELS:
5240, 5280 (7 kW NG, 6 kW LP)
5241, 5281 (9 kW NG, 10 kW LP)
5242, 5282 (13 kW NG, 13 kW LP)
5243, 5283 (15 kW NG, 16 kW LP)
5244, 5284 (15 kW NG, 16 kW LP)
DIAGNOSTIC
REPAIR MANUAL
AUTOMATIC STANDBY GENERATORS
www.guardiangenerators.com
DIAGNOSTIC
REPAIR MANUAL
AIR-COOLED

ELECTRICAL FORMULAS
TO FIND KNOWN VALUES 1-PHASE 3-PHASE
KILOWATTS (kW) Volts, Current, Power Factor E x I
1000
E x I x 1.73 x PF
1000
KVA Volts, Current E x I
1000
E x I x 1.73
1000
AMPERES kW, Volts, Power Factor kW x 1000
E
kW x 1000
E x 1.73 x PF
WATTS Volts, Amps, Power Factor Volts x Amps E x I x 1.73 x PF
NO. OF ROTOR POLES Frequency, RPM 2 x 60 x Frequency
RPM
2 x 60 x Frequency
RPM
FREQUENCY RPM, No. of Rotor Poles RPM x Poles
2 x 60
RPM x Poles
2 x 60
RPM Frequency, No. of Rotor Poles 2 x 60 x Frequency
Rotor Poles
2 x 60 x Frequency
Rotor Poles
kW (required for Motor) Motor Horsepower, Efficiency HP x 0.746
Efficiency
HP x 0.746
Efficiency
RESISTANCE Volts, Amperes E
I
E
I
VOLTS Ohm, Amperes I x R I x R
AMPERES Ohms, Volts E
R
E
R
E = VOLTS I = AMPERES R = RESISTANCE (OHMS) PF = POWER FACTOR

Contents
SPECIFICATIONS..................................................... 4
Generator ................................................................ 4
Stator Winding Resistance Values/
Rotor Resistance..................................................... 4
Engine ..................................................................... 5
Fuel Consumption ................................................... 5
Mounting Dimensions........................................... 6-7
Major Features ........................................................ 8
PART 1 - GENERAL INFORMATION ....................... 9
1.1 Generator Identification ................................... 10
1.2 Prepackaged Installation Basics ..................... 11
Introduction ......................................................11
Selecting A Location ........................................11
Grounding The Generator................................11
The Fuel Supply...............................................11
The Transfer Switch / Load Center...................11
Power Source And Load Lines.........................13
System Control Interconnections.....................13
1.3 Preparation Before Use................................... 14
General ............................................................14
Fuel Requirements...........................................14
Fuel Consumption............................................14
Reconfiguring The Fuel System.......................14
Engine Oil Recommendations .........................16
1.4 Testing, Cleaning and Drying........................... 16
Meters ............................................................17
The VOM..........................................................17
Measuring AC Voltage .....................................17
Measuring DC Voltage .....................................17
Measuring AC Frequency ................................17
Measuring Current ...........................................18
Measuring Resistance .....................................18
Electrical Units .................................................19
Ohm's Law .......................................................19
Visual Inspection..............................................20
Insulation Resistance.......................................20
The Megohmmeter...........................................20
Stator Insulation Resistance Test.....................21
Rotor Insulation Resistance Test......................22
Cleaning The Generator...................................22
Drying The Generator ......................................22
1.5 Engine-Generator Protective Devices ............. 23
General ............................................................23
Low Battery......................................................23
Low Oil Pressure Shutdown.............................23
High Temperature Switch .................................23
Overspeed Shutdown ......................................23
RPM Sensor Failure.........................................23
Overcrank Shutdown .......................................24
1.6 Operating Instructions ..................................... 25
Control Panel ...................................................25
To Select Automatic Operation ........................26
Manual Transfer To “Standby” And
Manual Startup....................................26
Manual Shutdown And Retransfer
Back To “Utility”....................................27
1.7 Automatic Operating Parameters .................... 28
Introduction ......................................................28
Automatic Operating Sequences .....................28
PART 2 - AC GENERATORS .................................. 29
2.1 Description and Components .......................... 30
Introduction ......................................................30
Engine-generator Drive System.......................30
The AC Generator............................................30
Rotor Assembly................................................30
Stator Assembly...............................................31
Brush Holder And Brushes ..............................31
Other AC Generator Components ...................31
2.2 Operational Analysis ....................................... 33
Rotor Residual Magnetism...............................33
Field Boost.......................................................33
Operation .........................................................34
2.3 Troubleshooting Flowcharts............................. 35
Problem 1 - Generator Produces Zero
Voltage or Residual Voltage .......... 35-36
Problem 2 - Generator Produces
Low Voltage at No-Load ......................37
Problem 3 - Generator Produces
High Voltage at No-Load .....................37
Problem 4 - Voltage and Frequency Drop
Excessively When Loads are Applied .38
2.3 Diagnostic Tests .............................................. 39
Introduction ......................................................39
Safety ............................................................39
Test 1 - Check Main Circuit Breaker.................39
Test 2 - Check AC Output Voltage....................39
Test 4 - Fixed Excitation Test/Rotor
Amp Draw Test ....................................40
Test 5 - Wire Continuity....................................41
Test 6 - Check Field Boost ...............................42
Test 7 - Testing The Stator With a VOM ...........42
Test 8 - Resistance Check of Rotor Circuit ......44
Test 9 - Check Brushes and Slip Rings............44
Test 10 - Test Rotor Assembly .........................45
Test 11 - Check AC Output Frequency.............45
Page 1

Test 12 - Check And Adjust Engine Governor
(Single Cylinder Units).........................46
Test 12A - Check Stepper Motor Control
(V-twin Engine Units)...........................46
Test 13 - Check And Adjust
Voltage Regulator................................48
Test 14 - Check Voltage And
Frequency Under Load........................48
Test 15 - Check For Overload Condition ..........48
Test 16 - Check Engine Condition....................48
PART 3 - "V-TYPE PREPACKAGED
TRANSFER SWITCHES.......................... 49
3.1 Description and Components .......................... 50
General ............................................................50
Enclosure.........................................................50
Transfer Mechanism.........................................51
Transfer Relay .................................................51
Neutral Lug ......................................................52
Manual Transfer Handle ..................................52
Terminal Block .................................................52
Fuse Holder .....................................................53
3.2 Operational Analysis ....................................... 54
Utility Source Voltage Available .......................56
Utility Source Voltage Failure ..........................57
Transfer To Standby ........................................58
Transfer To Standby ........................................59
Utility Restored.................................................60
Utility Restored, Transfer Switch
De-energized.......................................61
Utility Restored,
Retransfer Back To Utility ....................62
Transfer Switch In Utility...................................63
3.3 Troubleshooting Flow Charts ........................... 64
Introduction To Troubleshooting .......................64
Problem5-InAutomatic Mode,
No Transfer to Standby........................64
Problem6-InAutomatic Mode, Generator
Starts When Loss of Utility Occurs,
Generator Shuts Down When Utility
Returns But There Is
No Retransfer To Utility Power.............65
Problem 7 - Blown F1 or F2 Fuse ....................65
3.4 Diagnostic Tests .............................................. 66
General ............................................................66
Test 21 - Check Voltage at
Terminal Lugs E1, E2 ..........................66
Test 22 - Check Voltage at
Standby Closing Coil C2 .....................67
Test 23 - Test Transfer Relay TR ......................67
Test 24 - Check Manual Transfer
Switch Operation.................................68
Test 25 - Test Limit Switch XB1........................69
Test 26 - Check 23 And 194
Wiring/Connections .............................69
Test 27- Check Voltage At
Terminal Lugs N1, N2..........................70
Test 28 - Check Voltage At Utility 1
And Utility 2 Terminals.........................70
Test 29 - Check Voltage At
Utility Closing Coil C1..........................71
Test 30 - Check Fuses F1 And F2 ...................71
Test 31 - Test Limit Switch Xa1 ........................72
Test 32 - Continuity Test Of Wiring (C1)...........72
Test 33 - Continuity Test Of Wiring (C2)...........72
Test 34 - Check N1 And N2 Wiring ..................73
Test 35 - Check Transformer (Tx).....................73
PART 4 - DC CONTROL ......................................... 75
4.1 Description and Components .......................... 76
General ............................................................76
Terminal Strip / Interconnection Terminal.........76
Transformer (TX)..............................................76
Circuit Board ....................................................76
AUTO-OFF-MANUAL Switch ...........................80
15 Amp Fuse....................................................80
4.2 Operational Analysis ....................................... 82
Introduction ......................................................82
Utility Source Voltage Available........................82
Initial Dropout Of Utility Source Voltage ...........84
Utility Voltage Dropout And
Engine Cranking..................................86
Engine Startup And Running ...........................88
Initial Transfer To The “Standby” Source...........90
Utility Voltage Restored /
Re-transfer To Utility ............................92
Engine Shutdown ........................................... 94
4.3 Troubleshooting Flow Charts ........................... 96
Problem 8 - Engine Will Not Crank
When Utility Power Source Fails .........96
Problem 9 - Engine Will Not Crank
When AUTO-OFF-MANUAL Switch
is Set to "MANUAL".............................96
Problem 10 - Engine Cranks
but Won't Start.....................................97
Problem 11 - Engine Starts Hard and
Runs Rough / Lacks Power .................98
Problem 12 - Engine Starts and Runs,
Then Shuts Down................................99
Problem 13 - No Battery Charge ...................100
Problem 14 - Unit Starts and Transfer Occurs
When Utility Power is Available ........101
Page 2

Page 3
Problem 15 - Generator Starts
Immediately in Auto - No Transfer to
Standby. Utility Voltage is Present .....101
Problem 16 - 15 Amp Fuse (F1) Blown..........102
Problem 17 - Generator Will Not Exercise .....102
Problem 18 - No Low Speed Exercise ...........102
4.4 Diagnostic Tests ............................................ 103
Introduction .................................................. 103
Test 41 - Check Position Of
AUTO-OFF-MANUAL Switch ........... 103
Test 42 - Try A Manual Start ......................... 103
Test 43 - Test AUTO-OFF-MANUAL Switch . 103
Test 44 - Check Wire 15/15A/15B/239/0
Voltage ..............................................104
Test 45 - Check 15 Amp Fuse........................105
Test 46 - Check Battery .................................105
Test 47 - Check Wire 56 Voltage ...................106
Test 48 - Test Starter Contactor Relay
(V-twin Only)......................................106
Test 49 - Test Starter Contactor .....................106
Test 50 - Test Starter Motor............................107
Test 51 - Check Fuel Supply
And Pressure.....................................109
Test 52 - Check Circuit Board
Wire 14 Output ..................................110
Test 53 - Check Fuel Solenoid .......................111
Test 54 - Check Choke Solenoid
(V-twins Units Only)...........................112
Test 55 - Check For Ignition Spark.................113
Test 56 - Check Spark Plugs..........................114
Test 57 - Check Engine / Cylinder Leak Down
Test / Compression Test114
Test 58 - Check Shutdown Wire.....................115
Test 59 - Check And Adjust
Ignition Magnetos..............................116
Test 60 - Check Oil Pressure Switch
And Wire 86.......................................117
Test 61 - Check High Oil
Temperature Switch...........................118
Test 62 - Check And Adjust Valves ................119
Test 63 - Check Fuel Regulator
(7 Kw Natural Gas Units Only) ..........117
Test 64 - Check Battery Charge Output .........120
Test 65 - Check Transformer (TX)
Voltage Output...................................118
Test 66 - Check AC Voltage At
Battery Charger.................................121
Test 67 - Check Battery Charge
Relay (BCR) ......................................122
Test 68 - Check Battery Charge
Winding Harness...............................122
Test 69 - Check Battery Charger Wiring .......123
Test 70 - Check Wire 18 Continuity................123
Test 71 - Check N1 And N2 Voltage...............123
Test 72 - Check Utility Sensing Voltage
At The Circuit Board ..........................124
Test 73 - Test Set Exercise Switch .................124
Test 75 - Check Battery Voltage Circuit..........124
Test 76 - Check Cranking And
Running Circuits................................124
Test 77 - Test Exercise Function ....................126
Test 78 - Check Dip Switch Settings ..............126
Test 79 - Check Idle Control Transformer
(V-twin Units Only).............................126
Test 80 - Check LC1 & LC2 Wiring ................126
Test 81 - Check Idle Control Transformer
Primary Wiring...................................127
PART 5 - OPERATIONAL TESTS......................... 129
5.1 System Functional Tests................................ 130
Introduction ....................................................130
Manual Transfer Switch Operation .................130
Electrical Checks ...........................................130
Generator Tests Under Load..........................131
Checking Automatic Operation ......................132
Setting The Exercise Timer ............................132
PART 6 - DISASSEMBLY ..................................... 133
6.1 Major Disassembly ........................................ 134
Major Disassembly.........................................134
Front Engine Access......................................136
Torque Requirements
(Unless Otherwise Specified)............136
PART 7 - ELECTRICAL DATA .............................. 137
Drawing 0F7820 Wiring Diagram,
7kWHSB
Models 005240 & 005280 ................................... 138
Drawing 0F7821 Wiring Schematic,
7kWHSB
Models 005240 & 005280 ................................... 140
Drawing 0F7822 Wiring Diagram,
10, 13 & 16 kW HSB
Models 005241 & 005281
Models 005242 & 005282
Models 005243 & 005283
Models 005244 & 005284 ................................... 142
Drawing 0F7823 Schematic,
10, 13 & 16 kW HSB
Models 005241 & 005281
Models 005242 & 005282
Models 005243 & 005283
Models 005244 & 005284 ................................... 144
Drawing 0F9070 Wiring Diagram,
Transfer Switch
8 Circuit/16 Circuit ............................................... 146
Drawing 0F9775 Wiring Diagram,
Schematic
8 Circuit/16 Circuit ............................................... 147

Page 4
GENERATOR
Model 005240 & 005280 005241 & 005281 005242 & 005282 005243 & 005283
005244 & 005284
Rated Max. Continuous Power Capacity (Watts*) 6,000 NG/7,000 LP 9,000 NG/10,000 LP 13,000 NG/13,000 LP 15,000 NG/16,000 LP
Rated Voltage 120/240 120/240 120/240 120/240
Rated Max. Continuous Load Current (Amps)
120 Volts** 50.0 NG/58.3 LP 75.0 NG/83.3 LP 108.3 NG/108.3 LP 125 NG/133.3 LP
240 Volts 25.0 NG/29.2 LP 37.5 NG/41.7 LP 54.1 NG/54.1 LP 52.5 NG/66.6 LP
Main Line Circuit Breaker 30 Amp 45 Amp 55 Amp 65 Amp
Circuits***
50A, 240V - - - 1
40A, 240V - - 1 1
30A, 240V 1 1 1 -
20A, 240V - 1 - 1
20A, 120V 1 3 3 5
15A, 120V 5 3 5 5
Phase 1 1 1 1
Number of Rotor Poles 2 2 2 2
Rated AC Frequency 60 Hz 60 Hz 60 Hz 60 Hz
Power Factor 1 1 1 1
Recommended Air Filter Part # 0C8127 Part # 0E9581 Part # 0C8127 Part # 0C8127
Battery Requirement Group 26
12 Volts and
350 Cold-cranking
Amperes Minimum
Group 26
12 Volts and
525 Cold-cranking
Amperes Minimum
Group 26
12 Volts and
525 Cold-cranking
Amperes Minimum
Group 26
12 Volts and
525 Cold-cranking
Amperes Minimum
Battery Warming Blanket 0F6148DSRV
Weight (Unit Only) 336 Pounds 375 Pounds 425.5 Pounds 445 & 414 Pounds
Enclosure Steel/Aluminum
Normal Operating Range -20°F (-28.8°C) to 104°F (40°C)
* Maximum wattage and current are subject to and limited by such factors as fuel Btu content, ambient temperature, altitude, engine power and condition, etc. Maximum power
decreases about 3.5 percent for each 1,000 feet above sea level; and also will decrease about 1 percent for each 6° C (10° F) above 16° C (60° F) ambient temperature.
** Load current values shown for 120 volts are maximum TOTAL values for two separate circuits. The maximum current in each circuit must not exceed the value stated for 240 volts.
*** Circuits to be moved from main panel to transfer switch load center must be protected by same size breaker. For example, a 15 amp circuit in main panel must be a 15 amp circuit in
transfer switch.
STATOR WINDING RESISTANCE VALUES / ROTOR RESISTANCE
005240, 005280
(6/7 kW)
005241, 005281
(9/10 kW)
005242, 005282
(13/13 kW)
005243, 005283
005244, 005284
(15/16 kW)
Power Winding: Across 11 & 22 0.223-0.259 ohms 0.144 ohms 0.115 ohms 0.080 ohms
Power Winding: Across 33 & 44 0.223-0.259 ohms 0.144 ohms 0.115 ohms 0.080 ohms
Excitation Winding: Across2&6 1.528-1.769 ohms 1.238 ohms 1.256 ohms 1.092 ohms
Battery Charge Winding: Across 66 & 77 0.146-0.169 ohms 0.158 ohms 0.164 ohms 0.130 ohms
Rotor Resistance 11.88-13.76 ohms 11.8 ohms 12.6 ohms 22.0 ohms
SPECIFICATIONS

SPECIFICATIONS
Page 5
FUEL CONSUMPTION
Model # Natural Gas* LP Vapor**
1/2 Load Full Load 1/2 Load Full Load
005240, 005280 (6/7 kW) 66 119 0.82/30 1.47/54
005241, 005281 (9/10 kW) 102 156 1.25/46 1.93/70
005242, 005282 (13/13 kW) 156 220 1.55/57 2.18/80
005243, 005283 (15/16 kW)
005244, 005284 (15/16 kW) 173 245 1.59/59 2.51/92
* Natural gas is in cubic feet per hour.
**LP is in gallons per hour/cubic feet per hour.
Values given are approximate.
ENGINE
Model 005240 & 005280 005241 & 005281 005242 & 005282 005243 & 005283
005244 & 005284
Type of Engine GH-410 GT-530 GT-990 GT-990
Number of Cylinders 1 2 2 2
Rated Horsepower 14.5 @ 3,600 rpm 18 @ 3,600 rpm 30 @ 3,600 rpm 30 @ 3,600 rpm
Displacement 410cc 530cc 992cc 992cc
Cylinder Block Aluminum w/Cast Iron
Sleeve
Aluminum w/Cast Iron
Sleeve
Aluminum w/Cast Iron
Sleeve
Aluminum w/Cast Iron
Sleeve
Valve Arrangement Overhead Valves Overhead Valves Overhead Valves Overhead Valves
Ignition System Solid-state w/Magneto Solid-state w/Magneto Solid-state w/Magneto Solid-state w/Magneto
Recommended Spark Plug RC14YC BPR6HS RC12YC RC12YC
Spark Plug Gap 0.76 mm (0.030 inch) 0.76 mm (0.030 inch) 1.02 mm (0.040 inch) 1.02 mm (0.040 inch)
Compression Ratio 8.6:1 9.5:1 9.5:1 9.5:1
Starter 12 VDC 12 VDC 12 VDC 12 VDC
Oil Capacity Including Filter Approx. 1.5 Qts Approx. 1.7 Qts Approx. 1.7 Qts Approx. 1.7 Qts
Recommended Oil Filter Part # 070185B Part # 070185B Part # 070185B Part # 070185B
Recommended Air Filter Part # 0C8127 Part # 0E9581 Part # 0C8127 Part # 0C8127
Operating RPM 3,600 3,600 3,600 3,600

Page 6
SPECIFICATIONS
MOUNTING DIMENSIONS

Page 7
SPECIFICATIONS
MOUNTING DIMENSIONS

SPECIFICATIONS
Page 8
MAJOR FEATURES
Air Filter
Cover
Control
Panel
Fuel
Regulator
Battery CompartmentOil Filter
Exhaust
Enclosure
Oil
Dipstick
Data
Decal
Composite Base
Fuel
Inlet
(Back)
Air Filter
Cover Control
Panel
Fuel
Regulator
Battery CompartmentOil Filter
Exhaust
Enclosure
Oil
Dipstick
Data
Decal
Composite Base
Fuel
Inlet
(Back)
13 kW and 16 kW, V-twin GT-990 Engine
7 kW, Single Cylinder GH-410 Engine
Air Filter
Control
Panel
Fuel
Regulator
Battery CompartmentOil Filter
Exhaust
Enclosure
Oil
Dipstick
Data
Decal
Composite Base
Fuel
Inlet
(Back)
10 kW, V-twin GT-530 Engine

PART 1
GENERAL
INFORMATION
Air-cooled, Prepackaged
Automatic Standby Generators
Page 9
TABLE OF CONTENTS
PART TITLE PAGE
1.1 Generator Identification 10
1.2 Prepackaged Installation
Basics
11
1.3 Preparation Before Use 14
1.4 Testing, Cleaning and Drying 16
1.5 Engine-Generator Protective
Devices
23
1.6 Operating Instructions 25
1.7 Automatic Operating
Parameters
28
1.1 Generator Identification ................................... 10
1.2 Prepackaged Installation Basics ..................... 11
Introduction ......................................................11
Selecting A Location ........................................11
Grounding The Generator................................11
The Fuel Supply...............................................11
The Transfer Switch / Load Center...................11
Power Source And Load Lines.........................13
System Control Interconnections.....................13
1.3 Preparation Before Use................................... 14
General ............................................................14
Fuel Requirements...........................................14
Fuel Consumption............................................14
Reconfiguring The Fuel System.......................14
Engine Oil Recommendations .........................16
1.4 Testing, Cleaning and Drying........................... 16
Meters ............................................................17
The VOM..........................................................17
Measuring AC Voltage .....................................17
Measuring DC Voltage .....................................17
Measuring AC Frequency ................................17
Measuring Current ...........................................18
Measuring Resistance .....................................18
Electrical Units .................................................19
Ohm's Law .......................................................19
Visual Inspection..............................................20
Insulation Resistance.......................................20
The Megohmmeter...........................................20
Stator Insulation Resistance Test.....................21
Rotor Insulation Resistance Test......................22
Cleaning The Generator...................................22
Drying The Generator ......................................22
1.5 Engine-Generator Protective Devices ............. 23
General ............................................................23
Low Battery......................................................23
Low Oil Pressure Shutdown.............................23
High Temperature Switch .................................23
Overspeed Shutdown ......................................23
RPM Sensor Failure.........................................23
Overcrank Shutdown .......................................24
1.6 Operating Instructions ..................................... 25
Control Panel ...................................................25
To Select Automatic Operation ........................26
Manual Transfer To “Standby” And
Manual Startup....................................26
Manual Shutdown And Retransfer
Back To “Utility”....................................27
1.7 Automatic Operating Parameters .................... 28
Introduction ......................................................28
Automatic Operating Sequences .....................28

INTRODUCTION
This Diagnostic Repair Manual has been prepared
especially for the purpose of familiarizing service per-
sonnel with the testing, troubleshooting and repair of
air-cooled, prepackaged automatic standby genera-
tors. Every effort has been expended to ensure that
information and instructions in the manual are both
accurate and current. However, Generac reserves the
right to change, alter or otherwise improve the product
at any time without prior notification.
The manual has been divided into seven PARTS.
Each PART has been divided into SECTIONS. Each
SECTION consists of two or more SUBSECTIONS.
It is not our intent to provide detailed disassembly and
reassemble instructions in this manual. It is our intent
to (a) provide the service technician with an under-
standing of how the various assemblies and systems
work, (b) assist the technician in finding the cause of
malfunctions, and (c) effect the expeditious repair of
the equipment.
ITEM NUMBER:
Many home standby generators are manufactured
to the unique specifications of the buyer. The Model
Number identifies the specific generator set and its
unique design specifications.
SERIAL NUMBER:
Used for warranty tracking purposes.
Item # 0055555
1234567
120/240 AC
108.3/108.3
13000
Serial
Volts
Watts
1 PH, 60 HZ, RPM 3600
NEUTRAL FLOATING
CLASS F INSULATION
MAX OPERATING AMBIENT
TEMP - 120F/49C
FOR STANDBY SERVICE
MAX LOAD UNBALANCED - 50%
GENERAC POWER SYSTEMS
WAUKESHA, WI
MADE IN U.S.A.
Amps
Figure 1. A Typical Data Plate
Page 10
PART 1 GENERAL INFORMATION
SECTION 1.1
GENERATOR IDENTIFICATION

Page 11
GENERAL INFORMATION SECTION 1.2
PREPACKAGED INSTALLATION BASICS
INTRODUCTION
Information in this section is provided so that the ser-
vice technician will have a basic knowledge of instal-
lation requirements for prepackaged home standby
systems. Problems that arise are often related to poor
or unauthorized installation practices.
A typical prepackaged home standby electric system
is shown in Figure 1 (next page). Installation of such a
system includes the following:
• Selecting a Location
• Grounding the generator.
• Providing a fuel supply.
• Mounting the load center.
• Connecting power source and load lines.
• Connecting system control wiring.
• Post installation tests and adjustments.
SELECTING A LOCATION
Install the generator set as close as possible to the
electrical load distribution panel(s) that will be pow-
ered by the unit, ensuring that there is proper ventila-
tion for cooling air and exhaust gases. This will reduce
wiring and conduit lengths. Wiring and conduit not
only add to the cost of the installation, but excessively
long wiring runs can result in a voltage drop.
Control system interconnections non-prepackaged
generator consist of N1 and N2, and leads 23 and
194. Control system interconnection leads must be
run in a conduit that is separate from the AC power
leads. Recommended wire gauge size depends on
the length of the wire:
Max. Cable Length Recommended Wire Size
460 feet (140m) No. 18 AWG.
461 to 730 feet (223m) No. 16 AWG.
731 to 1,160 feet (354m) No. 14 AWG.
1,161 to 1850 feet (565m) No. 12 AWG.
GROUNDING THE GENERATOR
The National Electric Code requires that the frame
and external electrically conductive parts of the gen-
erator be property connected to an approved earth
ground. Local electrical codes may also require prop-
er grounding of the unit. For that purpose, a ground-
ing lug is attached to the unit. Grounding may be
accomplished by attaching a stranded copper wire of
the proper size to the generator grounding lug and to
an earth-driven copper or brass grounding-rod (elec-
trode). Consult with a local electrician for grounding
requirements in your area.
THE FUEL SUPPLY
Prepackaged units with air-cooled engines were oper-
ated, tested and adjusted at the factory using natural
gas as a fuel. These air-cooled engine units can be
converted to use LP (propane) gas by making a few
adjustments for best operation and power.
LP (propane) gas is usually supplied as a liquid in
pressure tanks. Both the air-cooled and the liquid
cooled units require a “vapor withdrawal” type of fuel
supply system when LP (propane) gas is used. The
vapor withdrawal system utilizes the gaseous fuel
vapors that form at the top of the supply tank.
The pressure at which LP gas is delivered to the
generator fuel solenoid valve may vary considerably,
depending on ambient temperatures. In cold weather,
supply pressures may drop to “zero”. In warm weath-
er, extremely high gas pressures may be encountered.
A primary regulator is required to maintain correct gas
supply pressures.
Current recommended gaseous fuel pressure at the inlet
side of the generator fuel solenoid valve is as follows:
LP NG
Minimum water column 10 inches 5 inches
Maximum water column 12 inches 7 inches
A primary regulator is required to ensure that proper
fuel supply pressures are maintained.
DANGER: LP AND NATURAL GAS ARE BOTH
HIGHLY EXPLOSIVE. GASEOUS FUEL LINES
MUST BE PROPERLY PURGED AND TESTED
FOR LEAKS BEFORE THIS EQUIPMENT IS
PLACED INTO SERVICE AND PERIODICALLY
THEREAFTER. PROCEDURES USED IN
GASEOUS FUEL LEAKAGE TESTS MUST
COMPLY STRICTLY WITH APPLICABLE FUEL
GAS CODES. DO NOT USE FLAME OR ANY
SOURCE OF HEAT TO TEST FOR GAS LEAKS.
NO GAS LEAKAGE IS PERMITTED. LP GAS IS
HEAVIER THAN AIR AND TENDS TO SETTLE IN
LOW AREAS. NATURAL GAS IS LIGHTER THAN
AIR AND TENDS TO SETTLE IN HIGH PLACES.
EVEN THE SLIGHTEST SPARK CAN IGNITE
THESE FUELS AND CAUSE AN EXPLOSION.
Use of a flexible length of hose between the genera-
tor fuel line connection and rigid fuel lines is required.
This will help prevent line breakage that might be
caused by vibration or if the generator shifts or settles.
The flexible fuel line must be approved for use with
gaseous fuels.
Flexible fuel line should be kept as straight as possi-
ble between connections. The bend radius for flexible
fuel line is nine (9) inches. Exceeding the bend radius
can cause the fittings to crack.
THE TRANSFER SWITCH / LOAD CENTER
A transfer switch is required by electrical code, to pre-
vent electrical feedback between the utility and stand-
by power sources, and to transfer electrical loads from
one power supply to another safely.
PREPACKAGED TRANSFER SWITCHES:
Instructions and information on prepackaged transfer
switches may be found in Part 3 of this manual.
PART 1

PART 1
Page 12
GENERAL INFORMATION
SECTION 1.2
PREPACKAGED INSTALLATION BASICS
Figure 1. Typical Prepackaged Installation
TO HOUSE BRANCH CIRCUITS SPLICED USING WIRE NUTS
CONNECTION OF GENERATOR
TO EXTERNAL CONNECTION PANEL
EXTERNAL CUSTOMER
CONNECTION BOX
4 PIN
CONNECTOR
100A OR 200A HOUSE MAIN SERVICE
EARTH SPIKE
GENERATOR GROUND (LOCATED ON THE REAR OF UNIT) NEUTRAL
BAR
GENERAC UL LISTED
PANEL BOARD GROUND
40A OR 70A 2-POLE
CIRCUIT BREAKER
EMERGENCY
CIRCUITS
194N1 N2 23
GENERATOR OUTPUT CIRCUIT BREAKER
2 POLE
NEUTRAL
GROUND
STUD
(8, 10, 12 OR 16 CIRCUIT
TRANSFER SWITCH)

GENERAL INFORMATION SECTION 1.2
PREPACKAGED INSTALLATION BASICS
POWER SOURCE AND LOAD LINES
The utility power supply lines, the standby (genera-
tor) supply lines, and electrical load lines must all be
connected to the proper terminal lugs in the transfer
switch. The following rules apply: In 1-phase systems
with a 2-pole transfer switch, connect the two utility
source hot lines to Transfer Switch Terminal Lugs N1
and N2. Connect the standby source hot lines (E1,
E2) to Transfer Switch Terminal Lugs E1 and E2.
Connect the load lines from Transfer Switch Terminal
Lugs T1 and T2 to the electrical load circuit. Connect
UTILITY, STANDBY and LOAD neutral lines to the
neutral block in the transfer switch.
SYSTEM CONTROL INTERCONNECTIONS
Prepackaged home standby generators are equipped
with a terminal board identified with the following ter-
minals: (a) UTILITY 1, (b) UTILITY 2, (c) 23, and (d)
194. Prepackaged load centers house an identically
marked terminal board. When these four terminals
are properly interconnected, dropout of utility source
voltage below a preset value will result in automatic
generator startup and transfer of electrical loads to
the “Standby” source. On restoration of utility source
voltage above a preset value will result in retransfer
back to that source and generator shutdown.
PART 1
Page 13
0000001
GAS MAIN
2-5 PSI
5-7" WC REGULATOR
TO HOUSEHOLD
GAS METER CAPABLE
119,000 (6/7KW)
156,000 (9/10KW)
220,000 (13kW)
+HOUSEHOLD APPLIANCES
}
FLOW OF:
OF PROVIDING FUEL
SAFETY
SHUT OFF
VALVE
(BASED ON 1000 BTU/CU FT)
245,000 (15/16KW)
BTU/HOUR
Figure 2. Proper Fuel Installation

GENERAL
The installer must ensure that the home standby gen-
erator has been properly installed. The system must
be inspected carefully following installation. All appli-
cable codes, standards and regulations pertaining to
such installations must be strictly complied with. In
addition, regulations established by the Occupational
Safety and Health Administration (OSHA) must be
complied with.
Prior to initial startup of the unit, the installer must
ensure that the engine-generator has been properly
prepared for use. This includes the following:
• An adequate supply of the correct fuel must be
available for generator operation.
• The engine must be properly serviced with the rec-
ommended oil.
FUEL REQUIREMENTS
With LP gas, use only the vapor withdrawal system.
This type of system uses the vapors formed above
the liquid fuel in the storage tank.
The engine has been fitted with a fuel carburetion
system that meets the specifications of the 1997
California Air Resources Board for tamper-proof dual
fuel systems. The unit will run on natural gas or LP
gas, but it has been factory set to run on natural gas.
Should the primary fuel need to be changed to LP
gas, the fuel system needs to be reconfigured. See
the Reconfiguring the Fuel System section for instruc-
tions on reconfiguration of the fuel system.
Recommended fuels should have a Btu content of
at least 1,000 Btus per cubic foot for natural gas; or
at least 2,520 Btus per cubic foot for LP gas. Ask the
fuel supplier for the Btu content of the fuel.
Required fuel pressure for natural gas is 5 inches to
7 inches water column (0.18 to 0.25 psi); and for liq-
uid propane, 10 inches to 12 inches of water column
(0.36 to 0.43 psi).
NOTE: All pipe sizing, construction and layout
must comply with NFPA 54 for natural gas applica-
tions and NFPA 58 for liquid propane applications.
Once the generator is installed, verify that the
fuel pressure NEVER drops below four (4) inches
water column for natural gas or 10 inches water
column for liquid propane.
Prior to installation of the generator, the installer
should consult local fuel suppliers or the fire marshal
to check codes and regulations for proper installation.
Local codes will mandate correct routing of gaseous
fuel line piping around gardens, shrubs and other
landscaping to prevent any damage.
Special considerations should be given when install-
ing the unit where local conditions include flood-
ing, tornados, hurricanes, earthquakes and unstable
ground for the flexibility and strength of piping and
their connections.
Use an approved pipe sealant or joint compound on
all threaded fitting.
All installed gaseous fuel piping must be purged and
leak tested prior to initial start-up in accordance with
local codes, standards and regulations.
FUEL CONSUMPTION
The fuel consumption rates are listed in the
SPECIFICATIONS section at the front of this manual.
BTU FLOW REQUIREMENTS - NATURAL GAS:
BTU flow required for each unit based on 1000 BTU
per cubic foot.
6/7 kW — 119,000 BTU/Hour
9/10 kW — 156,000 BTU/Hour
13 kW — 220,000 BTU/Hour
15/16 kW — 245,000 BTU/Hour
DANGER
Gaseous fuels such as natural gas and liquid
propane (LP) gas are highly explosive. Even
the slightest spark can ignite such fuels and
cause an explosion. No leakage of fuel is per-
mitted. Natural gas, which is lighter than air,
tends to collect in high areas. LP gas is heavi-
er than air and tends to settle in low areas.
NOTE: A minimum of one approved manual shut-
off valve must be installed in the gaseous fuel
supply line. The valve must be easily accessible.
Local codes determine the proper location.
RECONFIGURING THE FUEL SYSTEM
7 KW, 410CC ENGINE:
To reconfigure the fuel system from NG to LP, follow
these steps (Figure 1):
NOTE: The primary regulator for the propane sup-
ply is NOT INCLUDED with the generator. A fuel
pressure of 10 to 12 inches of water column (0.36
to 0.43 psi) to the fuel inlet of the generator must
be supplied.
1. Turn off the main gas supply (if connected).
2. Open the roof and remove the door.
3. Remove the battery (if installed).
4. Disconnect Wire 0 and Wire 14 from the gas solenoid on
top of the demand regulator.
5. Remove the carburetor fuel hose from the outlet port of
the demand regulator.
6. Remove the demand regulator by removing the fastener
that retains the regulator mounting bracket.
PART 1 GENERAL INFORMATION
SECTION 1.3
PREPARATION BEFORE USE
Page 14

GENERAL INFORMATION SECTION 1.3
PREPARATION BEFORE USE
7. Remove the square headed steel pipe plug from out-
let port #1 and the brass hose barb fitting from outlet
port #2.
8. Refit the brass hose barb fitting to outlet port #1 and the
square headed steel pipe plug to outlet port #2.
NG FUEL SYSTEM LP FUEL SYSTEM
FUEL HOSE
BRASS HOSE
FITTING BRASS HOSE
FITTING
FUEL JET
OUTLET
PORT
FUEL HOSE
ADJUSTMENT
SCREW
HOSE & PLUG
SWITCHED SIDES
PIPE
PLUG
PRESSURE
TAP
Figure 1. Demand Regulator
AIR
CLEANER
3/4” HOLE
Figure 2. Demand Regulator
NOTE: Use an approved pipe sealant or joint com-
pound on all threaded fittings to reduce the pos-
sibility of leakage.
9. Reverse procedure Steps 1-6 to reinstall demand
regulator.
10.Take the plastic plug supplied in the poly-bag with the
generator and press it into the 3/4” hole on the bottom
of the air cleaner base (Figure 2).
11.Reverse the procedure to convert back to natural gas.
12.Check for gas leakage at the pipe plug, hose connection
and fittings.
10, 13 AND 16 KW, V-TWIN ENGINES:
To reconfigure the fuel system from NG to LP, follow
these steps:
NOTE: The primary regulator for the propane sup-
ply is NOT INCLUDED with the generator. A fuel
pressure of 10 to 12 inches of water column (0.36
to 0.43 psi) to the fuel inlet of the generator must
be supplied.
FUEL SELECTION
LEVER -
“IN” POSITION FOR
NATURAL GAS
Figure 3. 10 kW, GT-530 (Inlet Hose Slid Back)
FUEL SELECTION
LEVER -
“OUT” POSITION FOR
LIQUID PROPANE
(VAPOR) FUEL
Figure 4. 10 kW, GT-530 (Inlet Hose Slid Back)
1. Open the roof.
2. For 10 kW units: Loosen clamp and slide back the
air inlet hose.
• Slide fuel selector on carburetor out towards the
back of the enclosure (Figures 3 and 4).
• Return the inlet hose and tighten clamp securely.
For 13 and 16 kW units: remove the air cleaner
cover.
PART 1
Page 15

• Slide the selector lever out towards the back of the
enclosure (Figures 5 and 6).
• Return the air cleaner cover and tighten the two
thumb screws.
3. Close the roof.
4. Reverse the procedure to convert back to natural gas.
FUEL SELECTION
LEVER -
“IN” POSITION FOR
NATURAL GAS
Figure 5. 13/16 kW, GT-990 (Airbox Cover Removed)
FUEL SELECTION
LEVER -
“OUT” POSITION FOR
LIQUID PROPANE
(VAPOR) FUEL
Figure 6. 13/16 kW, GT-990 (Airbox Cover Removed)
ENGINE OIL RECOMMENDATIONS
The primary recommended oil for units with air-
cooled, single cylinder or V-Twin engines is synthetic
oil. Synthetic oil provides easier starts in cold weather
and maximum engine protection in hot weather. Use
high quality detergent oil that meets or exceeds API
(American Petroleum Institute) Service class SG, SH,
or SJ requirements for gasoline engines. The follow-
ing chart lists recommended viscosity ranges for the
lowest anticipated ambient temperatures.
Engine crankcase oil capacities for the engines cov-
ered in this manual can be found in the specifications
section at the beginning of the book.
Lowest Anticipated
Ambient Temperature
Oil Grade (Recommended)
Above 60° F (16° C) Use SAE 30 oil
20° to 59° F (-7° to 15° C) Use SAE 10W-30 oil
Below 20° F (-7° C) SAE 5W-20/5W-30
For all seasons Use SAE 5W-30 Synthetic oil
PART 1
Page 16
GENERAL INFORMATION
SECTION 1.3
PREPARATION BEFORE USE

Page 17
GENERAL INFORMATION SECTION 1.4
TESTING, CLEANING AND DRYING
METERS
Devices used to measure electrical properties are
called meters. Meters are available that allow one
to measure (a) AC voltage, (b) DC voltage, (c) AC
frequency, and (d) resistance In ohms. The following
apply:
• To measure AC voltage, use an AC voltmeter.
• To measure DC voltage, use a DC voltmeter.
• Use a frequency meter to measure AC frequency In
“Hertz” or “cycles per second”.
• Use an ohmmeter to read circuit resistance, in
“ohms”.
THE VOM
A meter that will permit both voltage and resistance to
be read is the “volt-ohm-milliammeter” or “VOM”.
Some VOMs are of the “analog” type (not shown).
These meters display the value being measured by
physically deflecting a needle across a graduated
scale. The scale used must be Interpreted by the user.
“Digital” VOM's (Figure 1) are also available and are
generally very accurate. Digital meters display the
measured values directly by converting the values to
numbers.
NOTE: Standard AC voltmeters react to the
AVERAGE value of alternating current. When
working with AC, the effective value is used. For
that reason a different scale is used on an AC
voltmeter. The scale is marked with the effective
or “rms” value even though the meter actually
reacts to the average value. That is why the AC
voltmeter will give an Incorrect reading if used to
measure direct current (DC).
Figure 1. Digital VOM
MEASURING AC VOLTAGE
An accurate AC voltmeter or a VOM may be used to
read the generator's AC output voltage. The following
apply:
1. Always read the generator's AC output voltage only at
the unit's rated operating speed and AC frequency.
2. The generator's Voltage Regulator can be adjusted for
correct output voltage only while the unit is operating at
its correct rated speed and frequency.
3. Only an AC voltmeter may be used to measure AC
voltage. DO NOT USE A DC VOLTMETER FOR THIS
PURPOSE.
DANGER!: GENERATORS PRODUCE HIGH
AND DANGEROUS VOLTAGES. CONTACT
WITH HIGH VOLTAGE TERMINALS WILL
RESULT IN DANGEROUS AND POSSIBLY
LETHAL ELECTRICAL SHOCK.
MEASURING DC VOLTAGE
A DC voltmeter or a VOM may be used to measure
DC voltages. Always observe the following rules:
1. Always observe correct DC polarity.
a. Some VOM's may be equipped with a polar-
ity switch.
b. On meters that do not have a polarity switch,
DC polarity must be reversed by reversing
the test leads.
2. Before reading a DC voltage, always set the meter to a
higher voltage scale than the anticipated reading. If in
doubt, start at the highest scale and adjust the scale
downward until correct readings are obtained.
3. The design of some meters is based on the “current
flow” theory while others are based on the “electron
flow” theory.
a. The “current flow” theory assumes that
direct current flows from the positive (+) to
the negative (-).
b. The “electron flow” theory assumes that cur-
rent flows from negative (-) to positive (+).
NOTE: When testing generators, the “current flow”
theory is applied. That is, current is assumed to
flow from positive (+) to negative (-).
MEASURING AC FREQUENCY
The generator's AC output frequency is proportional
to Rotor speed. Generators equipped with a 2-pole
Rotor must operate at 3600 rpm to supply a frequency
of 60 Hertz. Units with 4-pole Rotor must run at 1800
rpm to deliver 60 Hertz.
PART 1

PART 1
Correct engine and Rotor speed is maintained by an
engine speed governor. For models rated 60 Hertz,
the governor is generally set to maintain a no-load fre-
quency of about 62 Hertz with a corresponding output
voltage of about 124 volts AC line-to-neutral. Engine
speed and frequency at no-load are set slightly high
to prevent excessive rpm and frequency droop under
heavy electrical loading.
MEASURING CURRENT
CLAMP-ON:
To read the current flow, in AMPERES, a clamp-on
ammeter may be used. This type of meter indicates
current flow through a conductor by measuring the
strength of the magnetic field around that conductor.
The meter consists essentially of a current trans-
former with a split core and a rectifier type instrument
connected to the secondary. The primary of the cur-
rent transformer is the conductor through which the
current to be measured flows. The split core allows
the Instrument to be clamped around the conductor
without disconnecting it.
Current flowing through a conductor may be mea-
sured safely and easily. A line-splitter can be used
to measure current in a cord without separating the
conductors.
Figure 2. Clamp-On Ammeter
Figure 3. A Line-Splitter
NOTE: If the physical size of the conductor or
ammeter capacity does not permit all lines to be
measured simultaneously, measure current flow
in each individual line. Then, add the Individual
readings.
IN-LINE:
Alternatively, to read the current flow in AMPERES,
an in-line ammeter may be used. Most Digital Volt
Ohm Meters (VOM) will have the capability to mea-
sure amperes.
This usually requires the positive meter test lead to be
connected to the correct amperes plug, and the meter
to be set to the amperes position. Once the meter is
properly set up to measure amperes the circuit being
measured must be physically broken. The meter will
be in-line or in series with the component being mea-
sured.
In Figure 4 the control wire to a relay has been
removed. The meter is used to connect and supply
voltage to the relay to energize it and measure the
amperes going to it.
1.00 A
BATTERY
+- RELAY
Figure 4. A VOM as an In-line meter
MEASURING RESISTANCE
The volt-ohm-milliammeter may be used to measure
the resistance in a circuit. Resistance values can be
very valuable when testing coils or windings, such as
the Stator and Rotor windings.
When testing Stator windings, keep in mind that the
resistance of these windings is very low. Some meters
are not capable of reading such a low resistance and
will simply read CONTINUITY.
If proper procedures are used, the following condi-
tions can be detected using a VOM:
• A “short-to-ground” condition in any Stator or Rotor
winding.
• Shorting together of any two parallel Stator wind-
ings.
• Shorting together of any two isolated Stator wind-
ings.
• An open condition in any Stator or Rotor winding.
Page 18
GENERAL INFORMATION
SECTION 1.4
TESTING, CLEANING AND DRYING