Troubleshooting flowcharts | Generac Power Systems 18 kW NG guide

AC generators

Part 2

Section 2.3 Troubleshooting flowcharts

General

Use the “Flow Charts” in conjunction with the detailed instructions in Section 2.4. Test numbers used in the flow charts correspond to the numbered tests in Section 2.4.

The first step in using the flow charts is to correctly identify the problem. Once that has been done, locate the problem on the following pages. For best results, perform all tests in the exact sequence shown in the flow charts.

Problem 1 - Generator Produces Zero Voltage or Residual Voltage

(12-20 kW)

TEST 1 - CHECK

MAIN CIRCUIT

BREAKER

RESET TO

“ON”

OR REPLACE

IF BAD

A

				RE-TEST
	TEST 4 - PERFORM		G
	FIXED EXCITATION /			REPAIR
	ROTOR AMP DRAW			REPAIR
			D	OR REPLACE
	B	C	D	FUSES
				FUSES

				CHECK
				VOM
				FUSES

TEST 7 - TEST		GOOD
		GOOD

STATOR


	TEST 11 -
	TEST 11 -				GOOD
	CHECK
	CHECK
	ROTOR
	ROTOR
	RESISTANCE

				BAD
				BAD

TEST 5 - WIRE

CONTINUITY

GOOD

TEST 6 -

FIELD BOOST

BAD

GOOD

REPLACE

VOLTAGE

REGULATOR

BAD

BAD

REPAIR

OR

REPLACE

REPAIR

OR

REPLACE

THEN

RETEST

PERFORM STATOR

INSULATION

RESISTANCE TEST

-

SECTION 1.4

BAD

TEST 12 -

BAD

CHECK

BRUSHES &

SLIP RINGS

GOOD

REPAIR

TEST 13 -

OR

BAD

TEST ROTOR

REPLACE

ASSEMBLY

GOOD

PERFORM ROTOR

BAD

INSULATION

RESISTANCE TEST

-

SECTION 1.4

Page 37

Image 39

Generac Power Systems 18 kW NG, 10 kW LP, 13 kW NG, 7 kW NG, 9 kW NG, 8 kW LP, 17 kW LP, 20 kW LP Troubleshooting flowcharts

Contents

Air-Cooled Product Electrical formulas Automatic Operating Sequences Problem 12 No Battery Charge 147 Specifications Fuel Consumption Engine Mounting Dimensions Right Side View Door removed Major Features Part General Information Rainproof Enclosure Fitted Rated Ambient Temp 40C Generator Identification PartIntroduction Neutral Floating Grounding The Generator Installation basicsTransfer Switch / Load Center Selecting a Location Typical Installation Installation basics Part Natural Gas Fuel Interconnections Power Source And Load Lines System Control Interconnections Non-Prepackaged Interconnections Part Control Wires from Transfer Switch PRE 08 HSB AIR-COOLED Generators Single & V-TWIN Engines Non-Prepackaged Interconnections Fuel Requirements Reconfiguring The Fuel SystemPreparation Before Use Part General Preparation before use Install the battery, door and close the roof Engine Oil Recommendations Measuring DC Voltage MetersVom Measuring AC Voltage Testing, cleaning and drying Part Measuring CurrentMeasuring Resistance Electrical Units Ohm’s LawVolts Amps Ohms ONE 1 Second Visual InspectionInsulation Resistance Megohmmeter Repeat between Wire 2 and Stator Lead Stator Insulation Resistance Test 12-20 kWStator Insulation Resistance Test 10 kW Drying The Generator Cleaning The GeneratorRotor Insulation Resistance Test 10 kW Rotor Insulation Resistance Test 12-20 kW Overspeed Shutdown Low BatteryHigh Temperature Switch Low Oil Pressure Shutdown Overcrank Shutdown Engine-generator protective devices Part Control Panel Operating Instructions Manual Transfer To Standby Manual Startup KW Installation AssistantOperating instructions Part To Select Automatic Operation Seconds then re-crank if additional crank cycles exist Automatic operating parameters Exercise Automatic operating parameters PartManual Auto Part AC Generators Rotor Assembly Engine-Generator Drive SystemAC Generator Description & components Stator Assembly Main Line Circuit Breaker Description & components PartBrush Holder And Brushes 12-20 kW Other AC Generator Components Field Boost 12-20 KW Rotor Residual Magnetism Startup Operational analysis PartOperation 8/10 kW Operation 12-20 kW Troubleshooting flowcharts Troubleshooting flowcharts Part Troubleshooting flowcharts Problem 3 Generator Produces Low Voltage at No-LoadProblem 4 Generator Produces High Voltage at No-Load Units with Results SafetyTest 1 Check Main Circuit Breaker Test 2 Check AC Output Voltage Test 4 Fixed Excitation Test Rotor Amp Draw Test Diagnostic tests PartRemove jumper lead connected to Wire 4 and Wire 15B Procedure Test 5 Wire Continuity 12-20 kW Diagnostic testsExample Test 7 Testing The Stator With a Vom 12-20 kW Reconnect WireTest 6 Check Field Boost 12-20 kW Repeat using stator lead Wire Test Control Panel Wires for ContinuityTest 8 Test Brushless Stator Repeat using stator lead Repeat using WireTest 9 Check Capacitor Measured Meter lead to WireRepeat using Wires 2 Test 10 Test DPE Winding on Brushless units If Continuity was measured in Steps 5 and 6 proceed to Step Remove Wire 4 from the voltage regulatorTest 11 Resistance Check Rotor Circuit 12-20 kW Test 12 Check Brushes And Slip Rings 12-20 kW Test 14 Check AC Output Frequency Test 13 Test Rotor Assembly 12-20 kW Remove air cleaner cover to access stepper motor Test 16 Check Stepper Motor Control V-twin Engine UnitsLoosen the governor clamp bolt Figure Pull ARM this Direction to Close Throttle Test 17 Check And Adjust Voltage Regulator 12-20 kW Test 21 Field Flash Alternator KW Units Refer back to flow chartTest 18 Check Voltage Frequency Under Load Test 20 Check Engine Condition Construction of Energizing Cord Page Transfer Item Description General Enclosure Transfer Relay Transfer Mechanism Utility N1 and N2 Neutral LugManual Transfer Handle Terminal Block Fuse Holder Fuses F1, F2Fuses F3 Operational Analysis Is a schematic for a typical W/V-Type transfer switch Operational analysis Is a wiring diagram for a typical W/V-Type transfer switch SW1 Utility Source Voltage Available Utility Source Voltage Failure Generator Power Available, Waiting to Transfer Transfer Action to Standby Position Transfer To Standby Generator Powering Load Utility Restored, Generator Still Providing Output to Load Utility Restored Utility Restored, Transfer Relay De-energized Utility Restored, Transfer Switch De-energized Utility Restored, Retransfer Back to Utility Utility Restored, Retransfer Back To Utility Transfer Switch in Utility Transfer Switch In Utility Troubleshooting flow charts Part Introduction To TroubleshootingProblem 7 In Automatic Mode, No Transfer to Standby Problem 9 Blown F1 or F2 Fuse Troubleshooting flow charts Check N1 & N2 Problem 14 No Battery Charge Load Shed Transfer Switch Problem 11 No Battery Charge Pre-Wire Load CenterProblem 12 No Battery Charge Rtsn & Rtse Transfer Switch Problem 13 No Battery Charge GenReady Load Center If the generator has been shut down, proceed as follows Test 26 Check Voltage at Terminal Lugs E1, E2 Manual Transfer Switch Operation Test 27 Check Manual Transfer Switch Operation Test 28 Check 23 and 15B Wiring Reconnect the J2 connector to the PCBPROCEDURE/ Results Remove the J2 connector from the circuit board Test 29 Test Transfer Relay TrSet VOM to measure DC voltage Test 30 Standby Control Circuit Test 31 Check Wire SW1 Test 32 Utility Control Circuit Output N2A Test 34 Check Fuses F1 and F2 Test 33 Test Limit Switch SW2 and SW3 Test 35 Check N1 and N2 Wiring Test 36 Check N1 and N2 VoltageReplace blown fuses as needed Test 37 Check Utility Sensing Voltage at the Circuit Board Test 38 Check Utility Sense VoltageTest 39 Check Voltage at Terminal Lugs N1, N2 Generator Transfer Switch Measure across points M and N VDC should be measured Test 40 Check Battery ChargerTest 42 Check Wire 0 and Wire15B Pre-wire load center Measure across points a and C VAC should be measured Rtsn & Rtse Transfer Switch Test 45 Check Wire 0/15B Rtsn & Rtse Transfer SwitchMeasure across points E and F VAC should be measured 15B Test 43, 44, and 45 Rtse Transfer Switch Test Points Disconnect the J2 connector from the printed circuit board Test 48 Check Wire 0/15B GenReady Load Center Section Load Shed Transfer Switch Measure across points C and D VAC should be measuredMeasure across points E and D VAC should be measured LSS ATSLSC Test 51 Check Wire 0 and Wire 15B Load Shed Transfer Switch Part DC Control Circuit Board Auto-Off-Manual SwitchDescription and components Part Terminal Strip / Interconnection Amp Fuse Description and components KW Printed Circuit Boards and J1 Connector Harness END Remote Wireless Connection J2 Connector PCB END J1 Connector Stepper Motor PCB END Harness END Harness END Remote Wireless Connection N1/N2 Connector 17 and 20 kW Printed Circuit Board and J1 Connector Menu System Navigation Choke Solenoid Connector Pin Number Identification Components Description Stator Circuit Condition Utility Source Voltage Available Initial Dropout of Utility Source Voltage Circuit Condition Initial Dropout of Utility Source Voltage Utility Voltage Dropout and Engine Cranking Circuit Condition Engine Cranking Engine Startup and Running Circuit Condition Engine Startup and Running Initial Transfer to the Standby Source Circuit Condition Initial Transfer to Standby Utility Voltage Restored / Re-transfer to Utility Circuit Condition Utility Voltage Restored Engine Shutdown Circuit Condition Retransfer to Utility and Engine Shutdown Controller Switch BAD Replace Controller Assembly Problem 17 Engine Cranks but Won’t Start Readjust Replace Choke Solenoid BAD Problem 19 Shutdown Alarm/Fault Occured Problem 20 7.5 Amp Fuse F1 Blown Problem 21 Generator Will Not ExerciseProblem 22 No Low Speed Exercise Test 56 Check Position Of Auto-Off Manual Switch Test 58 Auto-Off-Manual Switch Twin OnlyTest 57 Try a Manual Start Test 61 Check Battery Test 59 Test Auto OperationsTest 60 Check 7.5 Amp Fuse Typical Battery Load Tester Test Battery Condition Set a VOM to measure DC voltage Test 62 Check Wire 56 VoltageIf battery voltage is indicated in refer back to flow chart Test 63 Test Starter Contactor Relay V-twin Only Test 64 Test Starter Contactor Single Cylinder Engine Reconnect Wire 13 to the SCR Pinion Test 65 Test Starter MotorShorted, open or grounded armature Checking the Pinion Tools for Starter Performance Test Pinion Test 66 Check Fuel Supply Pressure PortSolenoid Removed 12-20 kW Gas Pressure Test point Test 67 Check Circuit Board Wire Output Disconnect the C3 Connector Test 68 Check Fuel SolenoidTest 69 Check Choke Solenoid Solenoid De-Energized, Choke Closed KW Units Approximately 3.7 ohms should be measured Disconnect the C3 Connector Set a VOM to measure DC voltage Disconnect C3 Connector Set a VOM to measure resistanceTest 70 Check for Ignition Spark KW Choke Solenoid Test 71 Check Spark Plugs Check Compression Test 73 Check Shutdown WireRemove a spark plug Repeat Steps 1 through 8 on remaining cylinder Depending on engine type, do the following Test 74 Check and Adjust Ignition Magnetos Magneto Setting Ignition Magneto Armature Air Gap Cylinder One Back, Short With oil level correct, try starting the engine Test 75 Check Oil Pressure Switch WireNavigate to the Digital inputs display screen Check engine crankcase oil level Remove the High Oil Temperature Switch Test 76 Check High Oil Temperature SwitchTest 77 Check and Adjust Valves Replace switch if it fails the test Test 78 Check Wire 18 Continuity Set the AUTO-OFF-MANUAL switch to the Manual positionBall Stud JAM NUT Test 79 Test Exercise Function Test 80 Check Cranking and Running CircuitsRecord the current date and time of the unit 8kW Choke Solenoid If the solenoid closed, replace the controller Test 81 Check to see if Low Speed Function is enabledDisconnect Wire 4 and Wire 0 from the Voltage Regulator VR Test 82 Check operation Choke Solenoid Part Operational Tests Set the generator main line circuit breaker to OFF or open Manual Transfer Switch OperationSystem functional tests Part Electrical Checks Generator Tests Under Load System functional tests Setting The Exercise Timer Verify that the AUTO-OFF-MANUAL switch is set to AutoChecking Automatic Operation Part Disassembly Major Disassembly Part Front Engine AccessRemove control harnesses Major Disassembly Section Section Major Disassembly Section Section Section Section Engine mount nuts with ground wires. See Figure Torque Requirements Unless Otherwise Specified Part Electrical Data Drawing #0G7945 Wiring Diagram, 8 kW Home Standby Part Wiring Diagram, 8 kW Home Standby Drawing #0G8511 Schematic, 8 kW Home Standby Part Part Schematic, 8 kW Home Standby Drawing #0G7946 Wiring Diagram, 10 kW Home Standby Part Part Wiring Diagram, 10 kW Home Standby Drawing #0G8512 Schematic, 10 kW Home Standby Part Part Schematic, 10 kW Home Standby Drawing #0G7947 Wiring Diagram, 14 kW Home Standby Part Part Wiring Diagram, 14 kW Home Standby Drawing #0G8513 Schematic, 14 kW Home Standby Part Part Schematic, 14 kW Home Standby Drawing #0G7948 Wiring Diagram, 17 kW Home Standby Part Part Wiring Diagram, 17 kW Home Standby Drawing #0G8514 Schematic, 17 kW Home Standby Part Part Schematic, 17 kW Home Standby Drawing #0G8186 Wiring Diagram, 20 kW Home Standby Part Part Wiring Diagram, 20 kW Home Standby Drawing #0G8515 Schematic, 20 kW Home Standby Part Part Schematic, 20 kW Home Standby Wiring Diagram, Home Standby Transfer Switch, 9/10/12/16 circuit Part Wiring Diagram, Home Standby Drawing #0G7959 Schematic, Home StandbyPage Page Page MyGenerac.com