Generac Power Systems 10 kW LP Operating instructions

diagnostic
repair
manual
AUTOMATIC STANDBY GENERATORS
Air-Cooled Product
MODELS:
7 kW NG, 8 kW LP
9 kW NG, 10 kW LP
13 kW NG, 14 kW LP
16 kW NG, 17 kW LP
18 kW NG, 20 kW LP

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

Page 1
Contents
Specifications..........................................................4
Generator................................................................ 4
Engine..................................................................... 5
Fuel Consumption................................................... 5
Mounting Dimensions.............................................. 6
Mounting Dimensions.............................................. 7
Major Features ........................................................ 8
PART 1 - GENERAL INFORMATION .......................9
1.1 Generator Identification................................... 10
Introduction......................................................10
1.2 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
Natural Gas Fuel Interconnections ..................13
1.3 Non-prepackaged Interconnections ................ 14
Connect a Pre-2008 Load Center Switch
To a Current or Future
Air-Cooled Generator...................................14
Connect a 2008 And Later Load Center
Switch to a Pre-2008
Air-Cooled Generator...................................15
1.4 Preparation Before Use................................... 16
General............................................................16
Fuel Requirements...........................................16
Fuel Consumption............................................16
Reconfiguring The Fuel System.......................16
Engine Oil Recommendations .........................18
1.5 Testing, Cleaning and Drying...........................19
Meters ............................................................19
The Vom...........................................................19
Measuring AC Voltage .....................................19
Measuring DC Voltage.....................................19
Measuring AC Frequency ................................19
Measuring Current...........................................20
Measuring Resistance .....................................20
Electrical Units.................................................21
Ohm’s Law.......................................................21
Visual Inspection..............................................22
Insulation Resistance.......................................22
The Megohmmeter...........................................22
Stator Insulation Resistance Test (12-20 kW) .....23
Stator Insulation Resistance Test (8-10 kW) .......23
Rotor Insulation Resistance Test (8-10 kW) ........24
Rotor Insulation Resistance Test (12-20 kW) ......24
Cleaning The Generator...................................24
Drying The Generator......................................24
1.6 Engine-Generator Protective Devices............. 25
General............................................................25
Low Battery......................................................25
Low Oil Pressure Shutdown.............................25
High Temperature Switch.................................25
Overspeed Shutdown ......................................25
Rpm Sensor Failure.........................................25
Overcrank Shutdown .......................................26
1.7 Operating Instructions..................................... 27
Control Panel ...................................................27
To Select Automatic Operation ........................28
Manual Transfer To “Standby”
and Manual Startup.....................................28
Manual Shutdown And
Retransfer Back To “Utility” ..........................28
1.8 Automatic Operating Parameters .................... 29
Introduction......................................................29
Automatic Operating Sequences.....................29
PART 2 - AC GENERATORS..................................31
2.1 Description and Components.......................... 32
Introduction......................................................32
Engine-Generator Drive System......................32
The AC Generator............................................32
Rotor Assembly................................................32
Stator Assembly...............................................33
Brush Holder And Brushes (12-20 kW) ...........34
Other AC Generator Components ...................34
2.2 Operational Analysis ....................................... 35
Rotor Residual Magnetism...............................35
Field Boost (12-20 kW)....................................35
Operation (8/10 kW).........................................36
Operation (12-20 kW) ......................................36
2.3 Troubleshooting Flowcharts............................. 37
Problem 1 – Generator Produces Zero
Voltage or Residual Voltage (12-20 kW)...37-38
Problem 2 – Generator Produces Zero
Voltage or Residual Voltage (8/10 kW)........38
Problem 3 – Generator Produces
Low Voltage at No-Load...............................39
Problem 4 – Generator Produces
High Voltage at No-Load..............................39
Problem 5 –Voltage and Frequency Drop
Excessively When Loads are Applied..........40
2.4 Diagnostic Tests .............................................. 41
Introduction......................................................41
Safety ............................................................41
Test 1 – Check Main Circuit Breaker................41
Test 2 – Check AC Output Voltage...................41
Test 4 – Fixed ExcitationTest/Rotor
Amp Draw Test ....................................42
Test 5 – Wire Continuity (12-20 kW) ................43
Test 6 – Check Field Boost (12-20 kW) ...........44

Test 7 – Testing The Stator With A Vom
(12-20 kW)...........................................44
Test 8 – Test Brushless Stator..........................45
Test 9 – Check Capacitor.................................46
Test 10 – Test DPE Winding on
Brushless units....................................47
Test 11 – Resistance Check Of Rotor Circuit
(12-20 kW)...........................................48
Test 12 – Check Brushes And Slip Rings
(12-20 kW)...........................................48
Test 13 – Test Rotor Assembly(12-20 kW).......49
Test 14 – Check AC Output Frequency............49
Test 15 – Check and Adjust Engine Governor
(Single Cylinder Units).........................49
Test 16 – Check Stepper Motor Control
(V-twin Engine Units)...........................50
Test 17 – Check And Adjust Voltage
Regulator (12-20 kW)..........................51
Test 18 – Check Voltage And Frequency
Under Load..........................................52
Test 19 –Check For Overload Condition...........52
Test 20 – Check Engine Condition...................52
Test 21 – Field Flash Alternator (8-10 kW) ......52
PART 3 -TRANSFER SWITCH...............................55
3.1 Description and Components.......................... 56
General............................................................56
Enclosure.........................................................56
Transfer Mechanism.........................................57
Transfer Relay..................................................57
Neutral Lug ......................................................58
Manual Transfer Handle ..................................58
Terminal Block .................................................58
Fuse Holder .....................................................59
3.2 Operational Analysis ....................................... 60
Operational Analysis........................................60
Utility Source Voltage Available .......................62
Utility Source Voltage Failure ..........................63
Transfer To Standby .........................................64
Transfer To Standby .........................................65
Utility Restored.................................................66
Utility Restored, Transfer Switch De-energized ...67
Utility Restored, Retransfer Back To Utility.......68
Transfer Switch In Utility...................................69
3.3 – Troubleshooting Flowcharts..........................70
Introduction To Troubleshooting .......................70
Problem 7 – In Automatic Mode,
No Transfer to Standby................................70
Problem 8 – In Automatic Mode, Generator
Starts When Loss of Utility Occurs,
Generator Shuts Down When Utility
Returns But There Is No Retransfer To Utility
Power / or Generator Transfers to Standby
During Exercise Or In Manual Mode............71
Problem 9 – Blown F1 or F2 Fuse...............71
Problem 10 – Units Starts And Transfer
Occurs When Utility Power Is On.................72
Problem 11 – No Battery Charge
(Pre-Packed Load Center)...........................73
Problem 12 – No Battery Charge
(RTSN & RTSE Transfer Switch) .................73
Problem 13 – No Battery Charge
(Gen-Ready Load Center)...........................73
Problem 14 – No Battery Charge
(Load Shed Transfer Switch)........................73
3.4 Diagnostic Tests .............................................. 74
General............................................................74
Test 26 – Check Voltage at
Terminal Lugs E1, E2..........................74
Test 27 – Check ManualTransfer Switch
Operation.............................................75
Test 28 – Check 23 And 15B
Wiring/Connections.............................76
Test 29 – Test Transfer Relay TR......................77
Test 30 – Standby Control Circuit ....................78
Test 31 – Check Wire 23..................................78
Test 32 – Utility Control Circuit.........................80
Test 33 – Test Limit Switch SW2 and SW3......82
Test 34 – Check Fuses F1 and F2...................82
Test 35 – Check N1 and N2 Wiring..................83
Test 36 – Check N1 and N2 Voltage ................83
Test 37 – Check Utility Sensing Voltage
at the Circuit Board..............................84
Test 38 – Check Utility Sense Voltage .............84
Test 39 – Check Voltage at
Terminal Lugs N1, N2..........................84
Test 40 – Check Battery Charger Supply
Voltage “Pre-Wire Load Center”..........86
Test 41 – Check Battery Charger Output
Voltage “Pre-Wire Load Center”..........86
Test 42 – Check Wire 0 and Wire15B
“Pre-Wire Load Center”.......................86
Test 43 – Check Battery Charger
Supply Voltage
“RTSN & RTSE Transfer Switch”.........87
Test 44 – Check Battery Charger
Output Voltage
“RTSN & RTSE Transfer Switch”.........87
Test 45 – Check Wire 0/
“RTSN & RTSE Transfer Switch”........87
Test 46 – Check Battery Charger
Supply Voltage
“GenReady Load Center”....................90
Test 47 – Check Battery Charger
Output Voltage
“GenReady Load Center”....................90
Test 48 – Check Wire 0/15B
“GenReady Load Center”....................90
Test 49 – Check Battery Charger
Supply Voltage
“Load Shed Transfer Switch”...............92
Test 50 – Check Battery Charger
Output Voltage
“Load Shed Transfer Switch”...............92
Test 51 – Check Wire 0 and Wire 15B
“Load Shed Transfer Switch”...............94
Page 2

Page 3
PART 4 - DC CONTROL.........................................95
4.1 Description and Components.......................... 96
General............................................................96
Terminal Strip / Interconnection Terminal.........96
Circuit Board....................................................96
Auto-Off-Manual Switch...................................96
7.5 Amp Fuse...................................................96
Menu System Navigation...............................102
4.2 Operational Analysis ..................................... 104
Introduction....................................................104
Utility Source Voltage Available......................104
Initial Dropout of Utility Source Voltage..........106
Utility Voltage Dropout and
Engine Cranking................................108
Engine Startup and Running..........................110
Initial Transfer to the “Standby” Source..........112
Utility Voltage Restored /
Re-transfer to Utility...........................114
Engine Shutdown...........................................116
4.3 Troubleshooting Flowcharts........................... 118
Problem 15 – Engine Will Not Crank
When Utility Power Source Fails................118
Problem 16 – Engine Will Not Crank When
AUTO-OFF-MANUAL Switch
is Set to “MANUAL.....................................118
Problem 17 – Engine Cranks
but Won’t Start...........................................119
Problem 18 – Engine Starts Hard and
Runs Rough / Lacks Power / Backfires......120
Problem 19 – Shutdown Alarm /
Fault Occurred...........................................121
Problem 20 – 7.5 Amp Fuse (F1) Blown.....122
Problem 21 – Generator Will Not Exercise...122
Problem 22 – No Low Speed Exercise........122
4.4 Diagnostic Tests ............................................ 123
Introduction ...................................................123
Test 56 – Check Position Of
Auto-Off- Manual Switch ..................123
Test 57 – Try a Manual Start .........................123
Test 58 – Auto-Off-Manual Switch
(V-Twin Only).....................................123
Test 59 – Test Auto Operations......................124
Test 60 – Check 7.5 Amp Fuse......................124
Test 61 – Check Battery.................................124
Test 62 – Check Wire 56 Voltage...................126
Test 63 – Test Starter Contactor Relay
(V-twin Only)......................................126
Test 64 – Test Starter Contactor
(Single Cylinder Engine)....................127
Test 65 – Test Starter Motor...........................128
Test 66 – Check Fuel Supply and Pressure...130
Test 67 – Check Circuit Board
Wire 14 Output..................................131
Test 68 – Check Fuel Solenoid......................132
Test 69 – Check Choke Solenoid...................132
Test 70 – Check for Ignition Spark.................134
Test 71 – Check Spark Plugs.........................136
Test 72 – Check Engine / Cylinder Leak
Down Test / Compression Test..........136
Test 73 – Check Shutdown Wire....................137
Test 74 – Check and Adjust
Ignition Magnetos..............................138
Test 75 – Check Oil Pressure Switch
and Wire 86.......................................141
Test 76 – Check High Oil
Temperature Switch...........................142
Test 77 – Check and Adjust Valves................142
Test 78 – Check Wire 18 Continuity...............143
Test 79 – Test Exercise Function ...................144
Test 80 – Check Cranking and
Running Circuits................................144
Test 81 – Check to see if Low Speed
Function is enabled...........................146
Test 82 – Check operation of the
Choke Solenoid.................................146
PART 5 - OPERATIONAL TESTS ........................147
5.1 System Functional Tests................................ 148
Introduction....................................................148
Manual Transfer Switch Operation.................148
Electrical Checks ...........................................148
Generator Tests Under Load..........................149
Checking Automatic Operation ......................150
Setting The Exercise Timer............................150
PART 6 - DISASSEMBLY .....................................151
6.1 Major Disassembly........................................ 152
Front Engine Access......................................152
Major Disassembly.........................................156
Torque Requirements
(Unless Otherwise Specified)............162
PART 7 - ELECTRICAL DATA..............................163
Wiring Diagram, 8 kW Home Standby................. 164
Schematic, 8 kW Home Standby......................... 166
Wiring Diagram, 10 kW Home Standby............... 168
Schematic, 10 kW Home Standby....................... 170
Wiring Diagram, 14 kW Home Standby............... 172
Schematic, 14 kW Home Standby....................... 174
Wiring Diagram, 17 kW Home Standby............... 176
Schematic, 17 kW Home Standby....................... 178
Wiring Diagram, 20 kW Home Standby............... 180
Schematic, 20 kW Home Standby....................... 182
Wiring Diagram, Home Standby Transfer Switch,
9/10/12/16 Circuit................................................ 184
Schematic, Home Standby Transfer Switch,
9/10/12/16 Circuit................................................ 186

Page 4
GENERATOR
Unit 8 kW 10 kW 12 kW 14 kW 16 kW 17 kW 20 kW
Rated Max. Continuous
Power Capacity (Watts*)
7,000 NG
8,000 LP
9,000 NG
10,000 LP
12,000 NG
12,000 LP
13,000 NG
14,000 LP
16,000 NG
16,000 LP
16,000 NG
17,000 LP
18,000 NG
20,000 LP
Rated Voltage 120/240
Rated Voltage at No-Load
(NG) 220-235 247-249
Rated Max. Continuous Load
Current (Amps)
120 Volts** (NG/LP)
240 Volts (NG/LP)
58.3/66.6
29.2/33.3
75.0/83.3
37.5/41.6
100.0/100.0
50.0/50.0
108.3/116.6
54.2/58.3
133.3/133.3
66.6/66.6
133.3/141.6
66.6/70.8
150.0/166.6
75.0/83.3
Main Line Circuit Breaker 35 Amp 45 Amp 50 Amp 60 Amp 65 Amp 65 Amp 100 Amp
Circuits*** 50A, 240V - - - 1 1 1 -
40A, 240V - - 1 1 1 1 -
30A, 240V 1 1 1 - - - -
20A, 240V - 1 - 1 1 1 -
20A, 120V 133455-
15A, 120V 5 3 5 4 5 5 -
Phase 1
Number of Rotor Poles 2
Rated AC Frequency 60 Hz
Power Factor 1
Battery Requirement Group 26R, 12
Volts and 350 CCA
Minimum
Group 26R, 12 Volts and 525 CCA Minimum
Weight (unit only in lbs.) 340 387 439 439 455 455/421 450
Enclosure Steel Steel Steel Steel Steel Steel/Aluminum Aluminum
Normal Operating Range -20° F (-28.8° C) to 77° F (25° 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 the 240 volts.
*** Circuits to be moved must be protected by same size breaker. For example, a 15 amp circuit in the main panel must be a 15 amp circuit in the transfer switch.
STATOR WINDING RESISTANCEVALUES / ROTOR RESISTANCE
8 kW 10 kW 12 kW 14 kW 16 kW 17 kW 20 kW
Power Winding: Across 11 & 22
0.123-0.1439 0.090-0.105 0.100-0.116 0.100-0.116 0.074-0.086 0.074-0.086 0.0415-0.0483
Power Winding: Across 33 & 44
0.123-0.1439 0.090-0.105 0.100-0.116 0.100-0.116 0.074-0.086 0.074-0.086 0.0415-0.0483
Excitation Winding: Across 2 & 6 0.776-0.902 0.511-0.594 0.876-1.018 0.876-1.018 0.780-0.906 0.780-0.906 0.731-0.850
Rotor Resistance
3.01-3.49 3.22-3.74 7.96-9.25 7.96-9.25 8.79-10.21 8.79-10.21 10.02-11.65
SPECIFICATIONS

SpecificationS
Page 5
Fuel Consumption
Model # Natural Gas* LP Vapor**
1/2 Load Full Load 1/2 Load Full Load
7/8 kW 77 140 0.94/34 1.68/62
9/10 kW 102 156 1.25/46 1.93/70
12/12 kW 152 215 1.53/56 2.08/76
13/14 kW 156 220 1.56/58 2.30/84
16/16 kW 183 261 1.59/58 2.51/91
16/17 kW 183 261 1.61/59 2.57/94
18/20 kW 206 294 1.89/69 2.90/106
* Natural gas is in cubic feet per hour.
**LP is in gallons per hour/cubic feet per hour.
Values given are approximate.
engine
Model 8 kW 10 kW 12/14/16/17 kW 20 kW
Type of Engine GH-410 GT-530 GT-990 GT-999
Number of Cylinders 1222
Rated Horsepower @ 3,600 rpm 14.8 18 32 34
Displacement 407cc 530cc 992cc 999cc
Cylinder Block Aluminum w/Cast Iron Sleeve
Valve Arrangement Overhead Valves
Ignition System Solid-state w/Magneto
Recommended Spark Plug RC14YC BPR6HS RC14YCA 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 9.4:1 9.5:1 9.5:1 9.5:1
Starter 12 VDC
Oil Capacity Including Filter Approx. 1.5 Qts Approx. 1.8 Qts Approx. 1.9 Qts Approx. 1.9 Qts
Recommended Oil Filter Part # 070185F
Recommended Air Filter Part # 0G3332 Part # 0E9581 Part # 0C8127 Part # 0G5894
Operating RPM 3,600

Page 6
SPECIFICATIONS
MOUNTING DIMENSIONS
AIR INTAKE
AIR OUTLET
FRONT OF UNIT
HOLE LOCATIONS FOR
OPTIONAL MOUNTING TO
A CONCRETE PAD
MINIMUM DISTANCE
AIR INTAKE
FRONT VIEW
LEFT SIDE VIEW
RIGHT SIDE VIEW
REAR VIEW
"DO NOT LIFT BY ROOF"
GROUNDING LUG
Ø30.2 [Ø1.2]
LIFTING HOLES 4 CORNERS
CABLE ACCESS HOLE
642
[25.3]
731.9
[28.8]
637.6
[25.1]
1226
[48.3]
250.0
[9.8]
446.6
[17.6]
378.7
[14.9]
44.8
[1.8]
530.0
[20.9]
575.3
[22.7]
76.2 [3.0]
PEA GRAVEL
MINIMUM
1218
[47.9]
1079.5
[42.5]
747
[29.4]
698
[27.5]
TRANSFER
SWITCH
8KW - 17KW
(IF SUPPLIED)
207
[8.2]
299
[11.8]
997
[39.3]
508
[20.0]
TRANSFER
SWITCH
20KW
(IF SUPPLIED)
454
[17.9]
FUEL INLET - 12-20KW (1/2" NPT)
8 & 10KW (3/4" NPT) - USE SUPPLIED ADAPTER
REQUIRED FUEL PRESSURE: NATURAL GAS = 5-7" WATER COLUMN
LIQUID PROPANE (VAPOR) = 10-12" WATER COLUMN
244.4
[9.6]
178.9
[7.0]
457.2
[18.0]
914 [36.0]
MINIMUM OPEN AREA
ON SIDES AND FRONT

Page 7
SPECIFICATIONS
MOUNTING DIMENSIONS
AIR INTAKE
AIR OUTLET
FRONT OF UNIT
HOLE LOCATIONS FOR
OPTIONAL MOUNTING TO
A CONCRETE PAD
MINIMUM DISTANCE
AIR INTAKE
FRONT VIEW
LEFT SIDE VIEW
RIGHT SIDE VIEW
REAR VIEW
"DO NOT LIFT BY ROOF"
GROUNDING LUG
Ø30.2 [Ø1.2]
LIFTING HOLES 4 CORNERS
CABLE ACCESS HOLE
642
[25.3]
731.9
[28.8]
637.6
[25.1]
1226
[48.3]
250.0
[9.8]
446.6
[17.6]
378.7
[14.9]
44.8
[1.8]
530.0
[20.9]
575.3
[22.7]
76.2 [3.0]
PEA GRAVEL
MINIMUM
1218
[47.9]
1079.5
[42.5]
747
[29.4]
698
[27.5]
TRANSFER
SWITCH
8KW - 17KW
(IF SUPPLIED)
207
[8.2]
299
[11.8]
997
[39.3]
508
[20.0]
TRANSFER
SWITCH
20KW
(IF SUPPLIED)
454
[17.9]
FUEL INLET - 12-20KW (1/2" NPT)
8 & 10KW (3/4" NPT) - USE SUPPLIED ADAPTER
REQUIRED FUEL PRESSURE: NATURAL GAS = 5-7" WATER COLUMN
LIQUID PROPANE (VAPOR) = 10-12" WATER COLUMN
244.4
[9.6]
178.9
[7.0]
457.2
[18.0]
914 [36.0]
MINIMUM OPEN AREA
ON SIDES AND FRONT

SPECIFICATIONS
Page 8
MAJOR FEATURES
Data Label
(see sample)
Oil
Dipstick
Exhaust
Enclosure
Composite Base Oil Filter Battery Compartment
Fuel
Regulator
Fuel Inlet
(back)
Air Filter
Circuit
Breaker
Control
Panel
Data Label
(see sample)
Oil
Dipstick
Exhaust
Enclosure
Composite Base Oil Filter Battery Compartment
Fuel
Regulator
Fuel Inlet
(back)
Air Filter
Circuit Breakers
GFCI Outlet
(All 17 & 20kW)
Control
Panel
Figure 1.3 – 12, 14, 16, 17 and 20kW, V-twin,
GT-990/GT-999 Engine (door removed)
8kW, Single Cylinder, GH-410 Engine
(door removed)
Data Label
(see sample)
Oil
Dipstick
Exhaust
Enclosure
Composite Base Oil Filter Battery Compartment
Fuel
Regulator
Fuel Inlet
(back)
Air
Filter
Circuit
Breaker
Control
Panel
10kW, V-twin, GT-530 Engine
(door removed)

PART 1
GENERAL
INFORMATION
Air-cooled, Automatic
Standby Generators
Page 9
TABLE OF CONTENTS
PART TITLE PAGE
1.1 Generator Identification 10
1.2 Installation Basics 11
1.3 Non-Prepackaged
Interconnections
14
1.3 Preparation Before Use 16
1.4 Testing, Cleaning and Drying 18
1.5 Engine-Generator Protective
Devices
25
1.6 Operating Instructions 27
1.7 Automatic Operating
Parameters
29
1.1 Generator Identification................................... 10
Introduction......................................................10
1.2 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
Natural Gas Fuel Interconnections ..................13
1.3 Non-prepackaged Interconnections ................ 14
Connect a Pre-2008 Load Center Switch
To a Current or Future
Air-Cooled Generator...................................14
Connect a 2008 And Later Load Center
Switch to a Pre-2008
Air-Cooled Generator...................................15
1.4 Preparation Before Use................................... 16
General............................................................16
Fuel Requirements...........................................16
Fuel Consumption............................................16
Reconfiguring The Fuel System.......................16
Engine Oil Recommendations .........................18
1.5 Testing, Cleaning and Drying........................... 19
Meters ............................................................19
The Vom...........................................................19
Measuring AC Voltage .....................................19
Measuring DC Voltage.....................................19
Measuring AC Frequency ................................19
Measuring Current...........................................20
Measuring Resistance .....................................20
Electrical Units.................................................21
Ohm’s Law.......................................................21
Visual Inspection..............................................22
Insulation Resistance.......................................22
The Megohmmeter...........................................22
Stator Insulation Resistance Test (12-20kW)...23
Stator Insulation Resistance Test (8-10kW).....23
Rotor Insulation Resistance Test (8-10kW)......24
Rotor Insulation Resistance Test (12-20kW)....24
Cleaning The Generator...................................24
Drying The Generator......................................24
1.6 Engine-Generator Protective Devices............. 25
General............................................................25
Low Battery......................................................25
Low Oil Pressure Shutdown.............................25
High Temperature Switch.................................25
Overspeed Shutdown ......................................25
Rpm Sensor Failure.........................................25
Overcrank Shutdown .......................................26
1.7 Operating Instructions..................................... 27
Control Panel ...................................................27
To Select Automatic Operation ........................28
Manual Transfer To “Standby”
and Manual Startup.....................................28
Manual Shutdown And
Retransfer Back To “Utility” ..........................28
1.8 Automatic Operating Parameters .................... 29
Introduction......................................................29
Automatic Operating Sequences.....................29

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, automatic standby generators. Every effort
has been expended to ensure that information and
instructions in the manual are both accurate and cur-
rent. However, changes, alterations or other improve-
ments may be made to the product at any time with-
out prior notification.
The manual has been divided into 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.
Page 10
PART 1 GENERAL INFORMATION
SECTION 1.1
GENERATOR IDENTIFICATION
Figure 1.Typical Data Plates
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%
Amps
MODEL #
SERIAL #
WATTS
VOLTS
AMPS
1PH, 60Hz, 3600 RPM, CLASS F INSULATION
RAINPROOF ENCLOSURE FITTED
RATED AMBIENT TEMP - 40°C
FOR STANDBY SERVICE, NEUTRAL FLOATING
0055555
1234567 120/240 AC
13000
108.3/108.3
Model Number - Serial Number -

Page 11
GENERAL INFORMATION SECTION 1.2
INSTALLATION BASICS
INTRODUCTION
Information in this section is provided so that the
service technician will have a basic knowledge of
installation requirements for home standby systems.
Problems that arise are often related to poor or unau-
thorized installation practices.
A typical 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 between the transfer
switch and generator consist of N1 and N2, and leads
23, 15B and 0. 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 RecommendedWire Size
35 feet (10.67m) No. 16 AWG.
60 feet (I8.29m) No. 14 AWG.
90 feet (27.43m) No. 12 AWG.
GROUNDINGTHE 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
Units with air-cooled engines were operated, 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 ANDTESTED
FOR LEAKS BEFORETHIS EQUIPMENT IS
PLACED INTO SERVICE AND PERIODICALLY
THEREAFTER. PROCEDURES USED IN
GASEOUS FUEL LEAKAGETESTS MUST
COMPLY STRICTLY WITH APPLICABLE FUEL
GAS CODES. DO NOT USE FLAME OR ANY
SOURCE OF HEATTOTEST FOR GAS LEAKS.
NO GAS LEAKAGE IS PERMITTED.LP GAS IS
HEAVIERTHAN AIR ANDTENDSTO SETTLE IN
LOW AREAS. NATURAL GAS IS LIGHTERTHAN
AIR ANDTENDSTO SETTLE IN HIGH PLACES.
EVENTHE 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.
THETRANSFER 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.
TRANSFER SWITCHES:
Instructions and information on transfer switches may
be found in Part 3 of this manual.
PART 1

PART 1
Page 12
GENERAL INFORMATION
SECTION 1.2
INSTALLATION BASICS
Figure 1.Typical Installation

GENERAL INFORMATION SECTION 1.2
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
Home standby generators are equipped with a termi-
nal board identified with the following terminals: (a)
UTILITY 1, (b) UTILITY 2, (c) 23, and (d) 15B. Load
centers house an identically marked terminal board.
When these four terminals are properly interconnect-
ed, 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
+HOUSEHOLD APPLIANCES
FUEL FLOW OF:
OF PROVIDING NATURAL GAS
SAFETY
SHUT OFF
VALVE(BASED ON 1000 BTU/CU FT)
BTU/HOUR
140,000 (7 kW)
156,000 (9 kW)
215,000 (12 kW)
220,000 (13 kW)
261,000 (16 kW)
294,000 (18 kW)
Figure 2. Proper Fuel Installation
NATURAL GAS FUEL INTERCONNECTIONS

Page 14
Part 1 GENERAL INFORMATION
Section 1.3
non-PrePackaged interconnectionS
DISCUSSION:
On the current model air-cooled generators Wire 194
was changed to 15B. Wire 15B is still utilized for posi-
tive voltage for the transfer relay andWire 23 is still the
control ground for transferring the generator. By follow-
ing the procedures below it is possible to connect new
product with Wire 15B to old or current product that
still utilize Wire 194, such as an RTS switch.
CONNECT A PRE-2008 LOAD CENTER SWITCHTO A
CURRENT OR FUTURE AIR-COOLED GENERATOR.
PROCEDURE:
1. Follow all instructions located in the Installation Manual
that was supplied with the unit regarding mounting of the
switch, junction box, and generator.
Note: When installing a standalone 5500 series
generator, the battery charger will be located in the
generator on the side of the control assembly.
2. Inside the Junction box between the generator and the
transfer switch there will be 5 wires coming from the
generator and 4 wires from the transfer switch.
3. Using the following diagram and UL approved wire nuts
connect the following wires together. Wire 0 will not be
utilized for this setup.
WIRE NUTS
N1 (BLU)
N2 (YEL)
23 (BRN)
194 (ORG)
N1 (YEL)
N2 (YEL)
23 (WHT)
15B (RED)
0 (BLK)
CONTROL WIRES FROM
ENGINE GENERATOR
CONTROL WIRES FROM
TRANSFER SWITCH
Figure 1.Wire Connections
WIRE
NUTS
N1 (BLU)
N2 (YEL)
23 (BRN)
194 (ORG)
N1 (YEL)
N2 (YEL)
23 (WHT)
15B (RED)
0 (BLK)
CONTROL WIRES FROM ENGINE GENERATOR
“08”& LATER HSB AIR-COOLED GENERATORS
SINGLE &V-TWIN ENGINES PRE“08” LOAD CENTER TRANSFER SWITCH
EXTERNAL CUSTOMER
CONNECTION BOX
INSTALL BATTERY CHARGER GENERAC P/N 0G8023
CONTROL WIRES FROM TRANSFER SWITCH
Figure 2. Post 2008 HSB Interconnections

GENERAL INFORMATION SECTION 1.3
NON-PREPACKAGED INTERCONNECTIONS
PART 1
CONNECT A 2008 AND LATER LOAD CENTER SWITCH
TO A PRE-2008 AIR-COOLED GENERATOR.
PROCEDURE:
1. Follow all instructions located in the Installation Manual
that was supplied with the unit regarding mounting of the
switch, junction box, and generator.
Note: When installing a standalone pre-2008 gen-
erator, the battery charger will be located in the
generator utilizing the 12 VDC trickle charger.
2. Inside the Junction box between the generator and the
transfer switch there will be 4 wires coming from the
generator and 5 wires from the transfer switch.
3. Using the following diagram and UL approved wire nuts
connect the following wires together. Wire 0 will not be
utilized for this setup.
Note: Remove the battery charger from the trans-
fer switch; it will not be utilized in the operation of
the generator.
WIRE NUTS
N1 (BLU)
N2 (YEL)
23 (BRN)
194 (ORG)
N1 (YEL)
N2 (YEL)
23 (WHT)
15B (RED)
0 (BLK)
CONTROL WIRES FROM
ENGINE GENERATOR
CONTROL WIRES FROM
TRANSFER SWITCH
Figure 3.Wire Connections
WIRE
NUTS
N1 (BLU)
N2 (YEL)
23 (BRN)
194 (ORG)
N1 (YEL)
N2 (YEL)
23 (WHT)
15B (RED)
0 (BLK)
CONTROL WIRES FROM ENGINE GENERATOR
PRE“08” HSB AIR-COOLED GENERATORS
SINGLE &V-TWIN ENGINES “08” & LATER LOAD CENTER TRANSFER SWITCH
EXTERNAL CUSTOMER
CONNECTION BOX
CONTROL WIRES FROM TRANSFER SWITCH
Figure 4. Pre-2008 HSB Interconnections Page 15

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.
7 kW - 140,000 BTU/Hour
9 kW - 156,000 BTU/Hour
12 kW - 215,000 BTU/Hour
13 kW - 220,000 BTU/Hour
16 kW - 261,000 BTU/Hour
18 kW - 294,000 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.
RECONFIGURINGTHE FUEL SYSTEM
8 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. Locate the plastic T-handle fuel selector in the poly bag
supplied with the generator.
5. Locate the selector knob on the air box cover, behind
the yellow air filter door and power bulge. The unit
comes from the factory in the NG (Natural Gas) position.
Grasping the T-handle, insert the pin end into the hole
PART 1 GENERAL INFORMATION
SECTION 1.4
PREPARATION BEFORE USE
Page 16

GENERAL INFORMATION SECTION 1.4
PREPARATION BEFORE USE
in the selector knob and pull out to overcome spring
pressure and then twist clockwise 90 degrees and allow
the selector to return in once aligned with the LP (Liquid
Propane) position.
6. Save this tool with the Owner's Manual.
7. Install the battery, door and close the roof.
8. Reverse the procedure to convert back to natural gas.
Figure 1. Demand Regulator
10, 12, 14, 16, 17 AND 20 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 2. 10 kW, GT-530 (Inlet Hose Slid Back)
FUEL SELECTION
LEVER -
“OUT” POSITION FOR
LIQUID PROPANE
(VAPOR) FUEL
Figure 3. 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 2 and 3).
• Returntheinlethoseandtightenclampsecurely.
For 12, 14, 16, 17 and 20 kW units: remove the air
cleaner cover.
• Slidetheselectorleverouttowardsthebackofthe
enclosure (Figures 4 and 5).
• 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 4. 12/14/16/17/20 kW, GT-990/GT-999
(Airbox Cover Removed)
PART 1
Page 17

FUEL SELECTION
LEVER -
“OUT” POSITION FOR
LIQUID PROPANE
(VAPOR) FUEL
Figure 5. 12/14/16/17/20 kW, GT-990/GT-999
(Airbox Cover Removed)
ENGINE OIL RECOMMENDATIONS
All oil should meet minimum American Petroleum
Institute (API) Service Class SJ, SL or better. Use
no special additives. Select the oil's viscosity grade
according to the expected operating temperature.
• SAE30èAbove 32° F
• 10W-30èBetween 40° F and -10° F
• Synthetic5W-30è10° F and below
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.
*
Any attempt to crank or start the engine
before it has been properly serviced with
the recommended oil may result in an
engine failure.
SAE 30
Synthetic 5W-30
10W-30
PART 1
Page 18
GENERAL INFORMATION
SECTION 1.4
PREPARATION BEFORE USE