Guardian Technologies 4760, 4456, 4390, 4389, 4759, 4758 specification

SECTION 4.2

OPERATIONAL ANALYSIS

PART 4

DC CONTROL

UTILITY VOLTAGE RESTORED / RE-

TRANSFER TO UTILITY

The "Load" is powered by the "Standby" power supply. The circuit board continues to seek an acceptable "Utility" source voltage. On restoration of "Utility" source voltage, the

	following events will occur:
	On restoration of utility source voltage above
	80 percent of the nominal rated voltage, a
	"retransfer time delay" on the circuit board
	starts timing. The timer will run for about
	fifteen (15) seconds.
	At the end of fifteen (15) seconds, the
	"retransfer time delay" will stop timing and
	circuit board action will open the Wire 23
	circuit to ground. The transfer relay (TR) will
	then de-energize.
	When the transfer relay (TR) de-energizes, its
	normally-closed contacts close. "Utility"
	source voltage is then delivered to the utility
	closing coil (C1), via Wires N1A/N2A, the
	closed TR contacts, Wire 126, limit switch
	XA1, and a bridge rectifier.
	The utility closing coil (C1) energizes and
	moves the main current carrying contacts to
	their "Neutral" position. The main contacts
	move to an over center position past "Neutral"
	and spring force closes them to their "Utility"
	side. "Load" terminals are now powered by
	the "Utility" source.
	Movement of the main contacts to ’Utility"	Figure 6. Circuit Condition - Utility Voltage Restored
	actuates limit switches XA1/XB1. XA1 opens	Figure 6. Circuit Condition - Utility Voltage Restored
	actuates limit switches XA1/XB1. XA1 opens
	and XB1 actuates to its "Standby" source
	side.
	The generator continues to run.

Page 4.2-11

Image 87

Guardian Technologies 4760 Utility Voltage Restored / RE Transfer to Utility, Circuit Condition Utility Voltage Restored

Contents

Diagnostic Repair Manual Diagnostic Repair Manual Electrical Formulas Engine Fuel ConsumptionStator Winding Resistance Values / Rotor Resistance Mounting Dimensions Specifications Major Features Part General Information Introduction Item NumberSerial Number Grounding the Generator Transfer Switch / Load CenterPrepackaged Transfer Switches Selecting a Location Prepackaged Installation Basics Part System Control Interconnections Power Source and Load Lines Fuel Requirements General Measuring AC Voltage Visual InspectionMeters VOM Measuring AC Frequency Measuring CurrentMeasuring Resistance Volt Electrical UnitsOhms LAW Ampere Insulation Resistance MegohmmeterStator Insulation Resistance Test Test Between Windings Testing ALL Stator Windings to Ground Cleaning the Generator Rotor Insulation Resistance TestDrying the Generator Overcrank Shutdown High OIL Temperature ShutdownLOW OIL Pressure Shutdown Overspeed Shutdown Auto position Control PanelOFF Position Manual Position Protection Systems SET Exercise SwitchTo Select Automatic Operation Manual Transfer to Standby Manual Startup Manual Shutdown and Retransfer Back to Utility Automatic Operating Sequences Automatic Operating Parameters SEQ. Condition Action SENSOR, Timer or Other Part AC Generators Rotor Assembly AC GeneratorENGINE-GENERATOR Drive System Excitation Circuit Breaker Stator AssemblyBrush Holder and Brushes Other AC Generator Components Main Line Circuit Breaker Voltage Regulator Rotor Residual Magnetism Field BoostField Boost Circuit Operation Troubleshooting Flowcharts Troubleshooting Flowcharts Part Section Section Discussion SafetyProcedure Test 1- Check Main Circuit Breaker Test 2- Check AC Output Voltage Test 3- Test Excitation Circuit BreakerIf a high voltage is indicated, go on to Test Set VOM to AC volts Test 4- Fixed Excitation Test Rotor AMP Draw Test Test 6 Check Field Boost Test 5 Wire Continuity Test 7 Testing the Stator with a VOM Set VOM to the Rx1 scale Test 8 Resistance Check Rotor Circuit Remove wire 4 from the voltage regulator Test 9 Check Brushes Slip RingsIf continuity was measured in steps 5 and 6 proceed to step Start the engine, let it stabilize and warm up at no-load Test 10 Test Rotor AssemblyTest 12 Check and Adjust Engine Governor Test 11 Check AC Output Frequency Loosen the governor clamp bolt Figure Procedure 7KW Units Test 16 Check Engine Condition Test 13 Check and Adjust Voltage RegulatorTest 15 Check for Overload Condition Test 14 Check Voltage Frequency Under Load Part Type Prepackaged Transfer Switches Enclosure Standby Closing Coil C2 Limit Switches XA1 and XB1Transfer Mechanism Utility Closing Coil C1 Terminal Block Transfer RelayNeutral LUG Manual Transfer Handle Fuses F1, F2 Fuse HolderUtility 1 Terminals 23 Operational Analysis Wiring Diagram and Schematic Utility Source Voltage Available Utility Source Power 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 Transfer Switch in Utility Transfer Switch in Utility Introduction to Troubleshooting Troubleshooting Flow Charts Part If the generator has been shut down, proceed as follows Test 21- Check Voltage AT Terminal Lugs E1, E2 Test 22 Check Voltage AT Standby Closing Coil C2 Continuity Results Test 24- Check Manual Transfer Switch OperationTest 23 Test Transfer Relay TR Now, connect the VOM test leads across Relay Terminals 1 Test 25- Test Limit Switch XB1 WIRING/CONNECTIONS PROCEDURE/RESULTSTest 27- Check Voltage AT Terminal Lugs N1, N2 Test 29- Check Voltage AT Utility Closing Coil C1 Utility 2 Terminals Test 30 Check Fuses F1 and F2 Test 31 Test Limit Switch XA1 See Test 32, Step Test 33 Continuity Test of Wiring C2Test 34 Check N1 and N2 Wiring Set the AUTO-OFF-MANUAL switch to the OFF position Test 35 Check Transformer TX Transformer TX Part DC Control Utility 1 and Utility Terminal Strip / InterconnectionTransformer TX Circuit Board Description and Components AMP Fuse AUTO-OFF-MANUAL Switch Control Panel Component Identification Circuit Condition Utility Source Voltage Available Operational Analysis Circuit Condition Initial Dropout of Utility Source Voltage Initial Dropout Utility Source Voltage Section Utility Voltage Dropout Engine Cranking Section Circuit Condition Engine Startup and Running Engine Startup and Running Section Initial Transfer to Standby Source Section Circuit Condition Utility Voltage Restored Utility Voltage Restored / RE Transfer to Utility Section Circuit Condition Retransfer to Utility and Engine Shutdown Engine Shutdown Operational Analysis Troubleshooting Flow Charts Part Troubleshooting Flow Charts Section Section Section Section Section Test 41 Check Position of AUTO-OFF Manual Switch Test 43- Test AUTO-OFF-MANUAL SwitchTest 42 TRY a Manual Start Set a VOM to measure DC voltage Replace AUTO-OFF-MANUAL switch, if defective Test 45- Check 15 AMP Fuse Test 46- Check BatteryInspect Battery Cables Test Battery State of Charge Test 48- Test Starter Contactor Relay V-TWIN only Test 47 Check Wire 56 VoltageTest Battery Condition If battery voltage is not indicated in , go to Test Starter Contactor Relay Test 49- Test Starter Contactor Checking the Pinion Test 50- Test Starter MotorShorted, open or grounded armature Conditions Affecting Starter Motor Performance Test Bracket TachometerTools for Starter Performance Test Measuring Current Remove Starter Motor Testing Starter Motor Test 51 Check Fuel Supply Pressure Testing Starter Motor Performance Test 52 Test Fuel Solenoid Test 53 Check Circuit Board Wire OutputDisconnect Wire 14 at the Fuel Solenoid FS Set the AUTO-OFF-MANUAL switch to OFF Test 55 Check for Ignition Spark Test 54 Check Fuel Solenoid Test 56 Check Spark Plugs Test 57- Check Engine CompressionIf sparking occurs but engine still wont start, go to Test Test 58 Check Shutdown Wire Test 59 Check and Adjust Ignition MagnetosIf ignition spark still has not occurred, proceed to Test Setting Ignition Magneto Armature Air Gap Do the following Test 60- Check OIL Pressure Switch WireCheck engine crankcase oil level With oil level correct, try starting the engine Remove the High Oil Temperature Switch Test 61- Check High OIL Temperature SwitchSwitch terminals Replace switch if it fails the test Test 62 Check and Adjust Valves Procedure Intake and ExhaustTest 63 Check Fuel Regulator Test 64 Check Battery Charge Output If voltage was not measured in , go to Test Test 66 Check AC Voltage AT Battery ChargerTest 65 Check Transformer TX Voltage Output Set a VOM to measure AC voltage BCR Test 68 Check Battery Charge Winding Harness Test 69 Check Battery Charger Wiring Test 70 Check Engine RUN WindingSet VOM to measure frequency 63 HZ should be measured Test 73 Test SET Exercise Switch Test 71 Check N1 and N2 VoltageAT the Circuit Board Test 74 Check Remote Start Wiring If Equipped Test 75 Check Battery Voltage CircuitTest 76 Check Cranking and Running Circuits Continuity Test 77 Test Exercise Function Part Operational Tests Manual Transfer Switch Operation Type Transfer SwitchesElectrical Checks Generator Tests Under Load Setting the Exercise Timer Verify that the AUTO-OFF-MANUAL switch is set to AutoChecking Automatic Operation Part Disassembly Major Disassembly Remove doorSTATOR/ROTOR/ENGINE Removal Major Disassembly Front Engine Access Follow Stator/Rotor/Engine removal procedures, StepsReverse the previous steps to re-assemble Part Electrical Data Model Part SCHEMATIC, 7 KW Home Standby Model 4456-0 Part SCHEMATIC, 12 & 15 KW Home Standby Drawing #0D9013-C 1 Part Wiring DIAGRAM, 7 KW Home Standby Drawing #0D9014-B 1 Drawing #0D9014-B 2 Model 4456-1 Part Wiring DIAGRAM, 12 & 15 KW Home Standby Drawing #0D8501-B 1 Drawing #0D8501-B 2 Part Electrical Data Part Page Page Xxxxxxxxxxxxxxxxxxxxxxxxxxx Xxxxxxxxxxxxxxxxxxxxxxxxxxx Part Procedure Section