Guardian Technologies 4270 manual Stator Insulation Resistance, Cloth or Compressed AIR

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Section 3

INSULATION RESISTANCE TESTS

DANGER!: DO NOT ATTEMPT TO WORK WITH SOLVENTS IN ANY ENCLOSED AREA. PROVIDE ADEQUATE VENTILATION WHEN WORKING WITH SOLVENTS. WITHOUT ADE- QUATE VENTILATION, FIRE, EXPLOSION OR HEALTH HAZARDS MAY EXIST . WEAR EYE PROTECTION. WEAR RUBBER GLOVES TO PROTECT THE HANDS.

CLOTH OR COMPRESSED AIR:

For small parts or when dry dirt is to be removed, a dry cloth may be satisfactory. Wipe the parts clean, then use low pressure air at 30 psi (206 Kpa) to blow dust away.

BRUSHING AND VACUUM CLEANING:

Brushing with a soft bristle brush followed by vacuum cleaning is a good method of removing dust and dirt. Use the soft brush to loosen the dirt, then remove it with the vacuum.

STATOR INSULATION RESISTANCE

GENERAL:

Insulation resistance is a measure of the integrity of the insulating materials that separate electrical wind- ings from the generator's steel core. This resistance can degrade over time due to the presence of conta- minants, dust, dirt, grease and especially moisture.

The normal insulation resistance for generator wind- ings is on the order of “millions of ohms” or “megohms”.

When checking the insulation resistance, follow the tester manufacturer's instructions carefully. Do NOT exceed the applied voltages recommended in this manual. Do NOT apply the voltage longer than one

(1) second.

CAUTION!: DO NOT connect the Hi-Pot Tester or Megohmmeter test leads to any leads that are routed into the generator control panel. Connect the tester leads to the Stator or Rotor leads only.

STATOR SHORT-TO-GROUND TESTS:

See Figure 3-2. To test the Stator for a short-to- ground condition, proceed as follows:

1.Disconnect and isolate all Stator leads as follows:

a.Disconnect sensing leads 11 and 22 from the voltage regulator.

b.Disconnect excitation winding lead No. 6 from the voltage regulator.

c.Disconnect excitation lead No. 2 from the excitation circuit breaker (CB2).

d.Disconnect battery charge winding leads No. 66 and 77 from the battery charge recti- fier (BCR).

e.Disconnect battery charge winding lead No. 55 from the battery charge resistor (R1).

f.At the main circuit breakers, disconnect sta- tor power leads No. 11P and 33.

g.At the ground stud (GND5), disconnect Stator power leads No. 22 and 33.

2.When all leads have been disconnected as outlined in Step 1 above, test for a short-to-ground condition as follows:

a.Connect the terminal ends of all Stator leads together (11, 22, 33, 44, 2,6, 55, 66, 77).

b.Follow the tester manufacturer's instructions carefully. Connect the tester leads across all Stator leads and to frame ground on the Stator can. Apply a voltage of 1500 volts. Do NOT apply voltage longer than one (1) second.

If the test indicates a breakdown in insulation, the Stator should be cleaned, dried and re-tested. If the winding fails the second test (after cleaning and dry- ing), replace the Stator assembly.

TEST BETWEEN ISOLATED WINDINGS:

1.Follow the tester manufacturer's instructions carefully. Connect the tester test leads across Stator leads No. 11 (POWER) and No. 2. Apply a voltage of 1500 volts- DO NOT EXCEED ONE SECOND.

2 6

11 11

22

22

33

44

55

66 77

Leads 2 & 6 =Stator Excitation Winding Leads 11 & 22 = Voltage Sensing Leads Leads 11 & 22, 33 & 44 = AC Power Windings Leads 55, 66, 77 = Battery Charge Windings

Figure 3-2. – Stator Leads

2.Repeat Step 1 with the tester leads connected across the fol- lowing Stator leads:

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Contents Diagnostic Repair Manual Replacement Parts SafetyTable of Contents 57-59 Magnetism Electromagnetic FieldsElectromagnetic Induction More Sophisticated AC Generator Simple AC GeneratorGenerator Operating Diagram Field Boost Generator AC Connection SystemLine Breakers 120 VAC only Connection for 120/240 VAC Dual Voltage LIC Grit or Abrasive to Clean Slip Rings Rotor AssemblyGeneral Battery Charge ComponentsBrush Holder Excitation Circuit ComponentsVoltage Regulator Adjust POT LEDAdjustment Procedure 162Control Panel Components Control Panel Component IdentificationInsulation Resistance Testers Cleaning the GeneratorEffects of Dirt and Moisture Drying the GeneratorStator SHORT-TO-GROUND Tests Brushing and Vacuum CleaningStator Insulation Resistance Cloth or Compressed AIRMegohmmeter Testing Rotor InsulationMeasuring DC Voltage MetersVOM Measuring AC VoltageMeasuring AC Frequency Measuring CurrentMeasuring Resistance Ohms LAW Electrical UnitsIntroduction Operational AnalysisCircuit CONDITION- OFF Circuit CONDITION- PRE-HEAT Circuit CONDITION- Cranking Circuit CONDITION-RUNNING Circuit CONDITION- Shutdown Circuit CONDITION- Fault Shutdowns Engine Control Circuit Board BatteryAdding Water Effects of TemperatureChecking Battery State of Charge Charging a BatteryStarter Contactor & Motor Preheat SwitchSTART/STOP Switch AMP FuseGlow Plugs Engine GovernorFuel Injection Pump Fuel NOZZLES/INJECTORSOverspeed Protection LOW OIL Pressure Switch High Coolant Temperature SwitchAdapter LOW OIL Pressure Switch Engine Protective DevicesTroubleshooting Flowcharts Troubleshooting Flowcharts Problem 3 No Battery Charge Output Troubleshooting Flowcharts Troubleshooting Flowcharts Troubleshooting Flowcharts Troubleshooting Flowcharts Troubleshooting Flowcharts Test 1- Check NO-LOAD Voltage Frequency Test 2 Check & AdjustTest 4- Fixed Excitation TEST/ROTOR AMP Draw Test 3- Test Excitation Circuit BreakerSet a VOM to its Rx1 scale Test 5- Wire ContinuityRe-connect Wire 11 and Wire 22 to the Voltage Regulator Test 6- Check Field BoostModel QP75D Test 7 Test Stator DPE Winding184W Test 8- Check Sensing Leads / Power WindingsTest 9- Check Brush Leads 159WTest 11- Check Rotor Assembly Tance Tests ProcedureTest 10 Check Brushes & Slip Rings Test 14- Check Load Watts & Amperage Test 15 Check Battery Charge OutputTest 12 Check Main Circuit Breaker Test 13- Check Load Voltage FrequencyTest 16 Check Battery Charge Rectifier Battery Charge Rectifier BCR is a full wave rectifierShort to Ground Test 20- Check Fuel Pump Test 19- Test PRE-HEAT SwitchSet a VOM to read battery voltage 12 VDC Test 18 TRY Cranking the EngineTest 21- Check 14 AMP Fuse Test 22- Check Battery & CablesTest 23- Check Power Supply to Circuit Board Disconnect the connector from the wires of the fuel pumpNot Activated Test 24 Check START-STOP SwitchTest 26- Test Starter Contactor Test 27 Check Starter MotorConditions Affecting Starter Motor Performance Measuring Current Checking the PinionPinion Tools for Starter Performance TestStarter motor test bracket may be made as shown in Figure Testing Starter MotorTachometer Test BracketTest 28- Check Fuel Supply Test 29 Check Wire 14 Power SupplyTest 30 Check Wire If Wire 18 checks GOOD, proceed to Problem 8 SectionTest 32- Test Preheat Contactor Test 33- Test Glow PlugsTest 34- Test D1 Diode Test 35- Check Valve Adjustment Remove the valve cover from engine Disconnect the batteryTest 36- Fuel Injector Pump Repeat Steps 1 through 8 on remaining cylinder If fuel is noted, proceed to next step in flowchartAdjust the regulated pressure on the gauge to 80 psi Down Test / Compression TestTest 38 Check OIL Pressure Switch Test 40- Test Water Temperature SwitchTest 39- Check Circuit Board for Ground Test 43 Check Wire 15 for Short to Ground If continuity is measure, replace the switchComponents for Short to Ground Major Disassembly Belt Tensioning RE-ASSEMBLYFAN Belt Line Corner UP Between 5˚ to 10˚Section Exploded Views / Part Numbers Bearing Carrier, Front Rotor AssemblyStator Assembly Flywheel AssemblyBase Frame Drawing No D2357-A Slide Latch Flush Door, Service RearDoor, Service Front Base Frame WeldmentEnclosure Drawing No D2358-D Decal, Battery + Cover, Access LiftCover, Access Electrical Gasket, Electrical AccessViews / Part Cover Plate, Scroll Weldment 25 26 Wire Assembly # Assembly, Potted RegulatorAssembly Marine Control Board Rectifier, Battery ChargingIntake and Exhaust System Drawing No D2362-B Hose, Air Inlet Exhaust GasketChamber Air Intake Air FilterViews / Part Numbers Wire Assembly, Black #4 Ground Fuel Pump AssemblyBoot, Battery Cable Cable, BatteryCustomer Controls Assembly Drawing No D2364-D Boot, Circuit Breaker Start / Stop SwitchSwitch, Pushbutton Spst Boot / Nut / Preheat SwitchGear Camshaft AssemblyCamshaft Gear KEY2630 Liter Diesel Cylinder Head Drawing No D2794 Liter Diesel Crankshaft, Piston and Flywheel Drawing No -B OIL Pump Cover Idler Gear AssemblySpring Thrust WasherExhaust Rocker ARM Rocker ARM AssemblyIncludes ALL Components Shown below Intake Rocker ARMLiter Diesel Injector Pump Drawing No -C Tank Return Model 04270 To Injection Pump To Fuel Pump 27 25 19 18 HOUSING, Timing Gear 3114 Liter Diesel Water Pump Drawing No Charts Generator Specifications Engine SpecificationsType Quietpact Model ROTOR/STATOR Resistance ValuesPage Data Data Electrical Data C4945 Schematic Drawing No C4945-A ModelC4946-A ElectricalSheet 2 OF4996 REV. 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