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Familiarization & Troubleshooting Guide

GENERATOR

BRIGGS & STRATTON CORPORATION

Milwaukee, WI 53201

Part No. 86262GS 9/05

Printed in U.S.A.

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86262GS Gen. Manual 6/30/06 12:13 PM Page 1

For Briggs & Stratton Discount Parts Call 606-678-9623 or 606-561-4983

www.mymowerparts.com

Содержание 86262GS

Страница 1: ...Familiarization Troubleshooting Guide GENERATOR For Briggs Stratton Discount Parts Call 606 678 9623 or 606 561 4983 www mymowerparts com...

Страница 2: ...ne who uses a procedure or method not described by the manufacturer must first satisfy himself that neither his safety nor the safety of the product will be endangered by the service or operating proc...

Страница 3: ...itches 23 Fuses 26 Circuit Breakers 26 Solenoids 27 Relays 28 Resistors 29 Transformers 31 Condensers 32 Rectifiers 33 Transistors 34 Brushes and Brush Holders 35 Voltage Regulator 37 Generator System...

Страница 4: ...roubleshooting Flowchart For Sincro Wound Brushless Type Generators 84 Voltage Regulator Adjustments 90 Generator Assemblies Generac Wound Generators 94 Disassembly 94 Assembly 101 Sincro Wound Genera...

Страница 5: ...other In a normal atom the positive charge of the nucleus exactly balances the negative charge of the electrons that rotate around it Borrowing Of Electrons If an atom loses electrons the positive ch...

Страница 6: ...theories is mentioned because the conventional theory is more commonly used in everyday applications For this guide however we will use the Electron Theory Electro Motive Force Current flow occurs in...

Страница 7: ...n or subtraction of heat energy will set these electrons free Figure 1 5 shows a union between iron and copper wires this union forms a thermocouple In Figure 1 5A the heat of the flame has caused the...

Страница 8: ...direction of magnetic lines of force around a wire you can use a simple rule called the Right Hand Rule Simply place your right hand around the wire with your thumb pointing in the direction of the c...

Страница 9: ...nt flow through a primary coil of wires creates a magnetic field around that coil which then cuts through a secondary coil of wires When the current flow through the primary wire coil is interrupted b...

Страница 10: ...10 amperes through 100 coils of wire will each create a magnetic field strength 1000 ampere turns Figure 1 13 The term ampere turns is the measure of the strength of a magnetic field Direct Current DC...

Страница 11: ...ee the Table 1 1 A wave diagram sine wave of alternating current shows that current goes from a zero value to maximum positive value 0 90 degrees and then returns to zero Figure 1 15 Two such current...

Страница 12: ...e is equal to a little over six thousand million billion electrons per second Written numerically the figure looks like this 6 000 000 000 000 000 000 Volt Unit of Pressure The volt is a measurement o...

Страница 13: ...s Law may be stated as follows Amperage will increase whenever voltage increases and resistance remains the same Amperage will decrease whenever resistance increases and voltage remains the same Ohm s...

Страница 14: ...ELECTRICAL FORMULAS Section 1 Generator Fundamentals Portable Generator Familiarization Troubleshooting Guide 12...

Страница 15: ...a series circuit is the sum of the individual resistances The total voltage across all resistances loads in series is the sum of the voltages across the individual resistances Thus total resistance ma...

Страница 16: ...d the total resistance of such a circuit first determine the resistance of each group The sum of the two group resistances is the total circuit resistance You can treat the two groups of resistances e...

Страница 17: ...TA Connected or Wye Connected Re connnectable Figure 1 26 Connections Affecting Circuits It is necessary to become familiar with some of the terms used to describe conditions which adversely affect th...

Страница 18: ...16 Section 1 Generator Fundamentals Portable Generator Familiarization Troubleshooting Guide Figure 1 26 Some Examples of 3 Phase Connection System...

Страница 19: ...netic field of the rotor has more wire turns to cut through on the stator The Revolving Magnetic Field The rotor is essentially an electro magnet The flow of direct current DC through its windings cre...

Страница 20: ...Section 1 Generator Fundamentals Portable Generator Familiarization Troubleshooting Guide 18...

Страница 21: ...er of parts However these parts are expensive and should not be replaced needlessly Replacement of parts as a result of guesswork while troubleshooting is not cost effective and should be avoided Figu...

Страница 22: ...e applied Several different engine manufacturers may be found on the various Generac Portable Products generator models They include Briggs Stratton Tecumseh Kawasaki Honda Robin Generac Power Systems...

Страница 23: ...half the driven speed of the 2 pole rotor Figure 2 3 Stator Assembly The word stator means stationary winding A voltage or electromotive force EMF is induced into the stator by the action of rotating...

Страница 24: ...citation winding AC output is delivered to a bridge rectifier Figure 2 8 which converts its output to direct current DC The rectifier direct current output is delivered to the rotor windings XL MC Ser...

Страница 25: ...A switch may be defined as a device used to open close or divert an electrical circuit You can actuate switches manually or automatically This discussion is devoted solely to manually operated switche...

Страница 26: ...ion Troubleshooting Guide Figure 2 12 Single Pole Single Throw SPST Figure 2 13 Single Pole Double Throw SPDT Figure 2 14 Double Pole Single Throw DPST Figure 2 17 Four Pole Double Throw 4PDT Figure 2...

Страница 27: ...n in Figure 2 19 In general this type of switch may be classified by The number of poles The number of positions Figure 2 20 illustrates single pole double pole 3 pole and 4 pole rotary switches 25 Se...

Страница 28: ...dings that are in series with the circuit to be protected When current flow exceeds a pre determined value the coil s magnetic field becomes strong enough to open a set of contact points and open or b...

Страница 29: ...l pressure shutdown switch used on some generator engines This type of switch is normally closed NC and is held open by engine oil pressure during engine operation Should engine oil pressure drop belo...

Страница 30: ...to the relay winding the spring holds the armature contacts against the upper fixed contact When current flow is applied to the winding a magnetic field is created The winding becomes an electromagne...

Страница 31: ...riable resistor is provided with some means of manipulating the length of the resistor element One type of variable resistor is called a potentiometer or rheostat which is usually wire wound The amoun...

Страница 32: ...nce to excessive voltages in circuits You could call them voltage sensitive Figure 2 34 shows a silicone carbide resistor along with its schematic symbol This type of variable resistor is often used t...

Страница 33: ...s indicated by the letter P When the switch is closed current flow through the primary winding increases which expands lines of magnetic force that cut across the secondary winding This causes a volta...

Страница 34: ...as heat energy in the resistor The capacitor will then be said to be discharged Figure 2 37 However if a wire is connected between the two plates if you touch the two capacitor wires together the exce...

Страница 35: ...ot flow in the opposite direction The rectifier thus permits one alternating current to pass but blocks the reverse alternation This action results in a pulsating direct current DC flow A rectifier th...

Страница 36: ...ight damage some components in a circuit or to protect transistors against excessive current flow For example A zener diode rated at 10VAC acts much like any other diode up to 10VAC However if the app...

Страница 37: ...rger current flow across the emitter collector Some Typical Transistors Some typical transistors are displayed in Figure 2 44 Generally the larger the transistor s physical size the more current it ca...

Страница 38: ...o terminals indicated by an E Wire 4 from the positive brush connects to the terminal indicated by a Brush lead 1 connects to the terminal More recent units are equipped with a rectifier and brush hol...

Страница 39: ...slip rings strengthening the magnetic field Voltage Regulator There are three variations of the voltage regulator shown in Figure 2 51 The regulator itself is the same for each one Only the connector...

Страница 40: ...tz AC frequency will provide a 60VAC output and so on A conventional voltage regulator provides a fixed voltage output regardless of frequency If output frequency is held constant voltage will remain...

Страница 41: ...o have a system control circuit board which is usually housed in the control or receptacle panel Operation of this type of system is similar to the conventional voltage regulator system However voltag...

Страница 42: ...the power regulator board to turn on and increase current flow to the rotor This causes the rotor s magnetic field strength to increase and actual voltage to increase When actual voltage is more than...

Страница 43: ...e winding is changed to direct current DC by one or more diodes in the circuit Early production units were equipped with battery charge circuits as shown in Figure 2 61 consisting of a single winding...

Страница 44: ...in the rotor creates magnetic lines of flux which cut through stator windings A and B to induce an EMF into both windings Winding B is the Direct Excitation Winding The EMF induced into this winding...

Страница 45: ...excitation current is taken from instead of having an A and B winding Compare Figure 2 64 with 2 66 The operation of a Reactor Excited alternator may be described as follows The Rotor turns at a pre...

Страница 46: ...t is intersected by the rotor winding as it is spun by the engine That induces an AC voltage in the rotor winding that is converted to a DC voltage by a diode in the rotor winding This creates an elec...

Страница 47: ...g start up residual AC voltage is delivered to the PTC and diode from the stator power winding When the thermistor is cold resistance is low Current can flow to the diode where the AC current is recti...

Страница 48: ...e power Such a condition would exist when a reactance condition occurs in a circuit To help explain the reason for apparent and true power ratings of reactance circuits mechanical work can be related...

Страница 49: ...47 Section 2 Generator Components Systems Portable Generator Familiarization Troubleshooting Guide Figure 2 73 Determining The Power Factor...

Страница 50: ...ash while the engine is cranking To reset the float switch and allow the engine to start fill the crankcase to the proper level with the recommended oil THE V TWIN ENGINE SYSTEM The V Twin engine has...

Страница 51: ...below approximately 10 psi 0 32 kg per cm2 The system control circuit board provides a time delay that allows oil pressure to build during initial cranking The delay permits the engine to run for abou...

Страница 52: ...is shut down the throttle is held against the high speed side of a throttle stop During operation at no load and with the idle control switch set to OFF the flapper will be at approximately the no loa...

Страница 53: ...the coil and reduce engine speed to idle Early V Twin Engine Idle Control The V Twin idle control system operates in a fashion similar to the idle control on other portable generators For units with i...

Страница 54: ...ose the circuit to the idle control coil delivering 120VDC to the coil With the coil energized the governor lever will be pulled in to reduce engine speed to idle about 40 45 Hertz When electrical loa...

Страница 55: ...secondary windings The idle control board will sense there is no load on the generator and will send a signal to the idle control stepper motor The stepper motor will move to the low idle position wh...

Страница 56: ...54 Section 2 Generator Components Systems Portable Generator Familiarization Troubleshooting Guide...

Страница 57: ...bare wires terminals etc Never permit an untrained person to service or assist with the procedures discussed in this guide Never handle any kind of electrical cord or device while standing in water wh...

Страница 58: ...HOOTING IDLE CONTROLS Section 3 Generator Diagnostics and Adjustments Portable Generator Familiarization Troubleshooting Guide control Figure 3 1 Idle Control Troubleshooting Flow Chart 3500 7500 Watt...

Страница 59: ...s an electromagnet Touch the shaft of a screwdriver to the idle control coil If the solenoid is energized the screwdriver should stick to the side of the coil If the screwdriver sticks but the engine...

Страница 60: ...with the idle control switch ON The system control board is bad Check the idle control coil for shorts NOTE A shorted coil can damage the system control board Be sure to adjust the voltage potentiome...

Страница 61: ...59 Section 3 Generator Diagnostics and Adjustments Portable Generator Familiarization Troubleshooting Guide...

Страница 62: ...tion 3 Generator Diagnostics and Adjustments Portable Generator Familiarization Troubleshooting Guide Figure 3 4 Idle Control Troubleshooting Flow Chart 480 570 V Twin GN Engines 8000 10000 Watt Gener...

Страница 63: ...but DC voltage is not present at pins J2 and J3 check for a failure in the battery charge circuit of the generator Test 3 Check Idle Control Switch Operation Remove wires 83 and 84 from the idle cont...

Страница 64: ...ess and the stepper motor housing ground the VOM should read infinity If any reading other than listed is noted replace the stepper motor and harness as an assembly Early Idle Control Adjustment Excep...

Страница 65: ...eed Turn the idle mixture valve in lean until the engine begins to roughen and then out rich until it roughens Take note of these positions Set idle mixture valve midway between rich and lean Recheck...

Страница 66: ...cy adjustments should only be done after successfully completing the No Load adjustments Refer to Figure 3 12 Perform steps with the engine running at its correct no load frequency Then proceed as fol...

Страница 67: ...t NOTE The Idle Control Switch adjustment should only be done after successfully completing No Load Rated Load and Low Idle frequency adjustments Proceed with the idle control switch adjustments with...

Страница 68: ...pm For units rated at 50 Hertz Meter should read About 50 5 51 5 Hertz 3030 3090 rpm Set the idle control switch to ON The idle control solenoid should energize to pull the governor lever in and engin...

Страница 69: ...Using a phillips screwdriver Adjust the low speed adjustment screw Figure 3 16 to 45 Hz Turn the Idle Switch to OFF Adjust the high speed adjustment screw Figure 3 16 to 62 Hz no load Cycle the idle...

Страница 70: ...TING GENERATOR UNITS Section 3 Generator Diagnostics and Adjustments Portable Generator Familiarization Troubleshooting Guide or later Figure 3 17 Troubleshooting Flow Chart For Direct Excited Brush T...

Страница 71: ...ple process involving a DC battery This usually occurs if the unit is out of use for a long period of time NOTE Some units are equipped with FIELD BOOST and should never lose residual magnetism unless...

Страница 72: ...r voltage regulator For that reason if a rotor has failed be sure to check the bridge rectifier voltage regulator or power regulator board Before testing the rotor inspect the brushes and slip rings R...

Страница 73: ...4 and the positive post on a 12VDC battery Connect a jumper wire between the negative brush and the negative post on the battery See Figure 3 23 Start the engine and monitor amp draw It should not ch...

Страница 74: ...h resistance indicates an opening in the excitation winding A low reading indicates a shorted stator winding Connect one test lead to a stator power wire Connect the other test lead to one of the stat...

Страница 75: ...wer Windings Set a VOM to the OHM scale Connect the test leads to the stator wires 11 and 22 Measure the resistance and compare it to the nominal resistance from the appropriate table Briggs Stratton...

Страница 76: ...fier NOTE Bypassing the bridge rectifier and voltage regulator are similar tests the difference being that six wires are unplugged from the voltage regulator where only two or four are removed from th...

Страница 77: ...tor current draw is within specification The problem is in the stator windings If the rotor current draw Test 3 is higher than specified A flying short exists in the rotor If current draw Test 3 is lo...

Страница 78: ...76 Section 3 Generator Diagnostics and Adjustments Portable Generator Familiarization Troubleshooting Guide Figure 3 31 Troubleshooting Flow Chart For Brush Type Generators With Two Board Regulation...

Страница 79: ...by flashing the field with a simple process involving a DC battery This usually occurs if the unit is out of use for a long period of time NOTE Some units are equipped with FIELD BOOST and should nev...

Страница 80: ...was disconnected Figure 3 34 Start the engine Measure the voltage at the 120VAC panel receptacle It should read less than 10VAC If the voltage is less than 10VAC The failure is in the System Control B...

Страница 81: ...stator windings Refer to Checking Rotor Resistance Checking Stator Windings and or Rotor Current Draw Test If the voltage is below 60VAC at the outlets but above 60VAC at the excitation leads Shut the...

Страница 82: ...nce table Briggs Stratton Power Products Portable Generator Rotor Stator Resistance Tables Pub 87971 Rev 6 or later A reading of infinity or a very high resistance indicates an open circuit or a parti...

Страница 83: ...s higher than specified a flying short exists in the rotor If current draw is lower than specified a flying open exists in the rotor If current draw is within specifications rotor is OK Test 8 Check S...

Страница 84: ...ting Single Voltage Type Power Winding Set a VOM to its OHM scale Connect the meter test leads across the AC power wires Wire 11 and wire 22 or blue and red wires Figure 3 44 Measure the resistance an...

Страница 85: ...or Stator Resistance Tables Pub 87971 Rev 6 or later Connect the test leads to the stator wires 22 and 44 Measure the resistance and compare it to the nominal resistance from the appropriate table Ana...

Страница 86: ...84 Section 3 Generator Diagnostics and Adjustments Portable Generator Familiarization Troubleshooting Guide Figure 3 46 Troubleshooting Flow Chart For Sincro Wound Brushless Type Generators...

Страница 87: ...excitation system an energizing cord may be made locally Figure 3 47 Make sure the generator is completely assembled Plug one end of the energizing cord into one of the panel 120VAC receptacles Start...

Страница 88: ...citation wires Figure 3 51 Measure the resistance and compare it to the nominal resistance from the appropriate table Briggs Stratton Power Products Portable Generator Rotor Stator Resistance Tables P...

Страница 89: ...r test lead to the stator power winding Figure 3 55 A reading of infinity should be measured A reading of other than infinity indicates a stator winding shorted to ground Testing Dual Voltage Type Pow...

Страница 90: ...rotor capacitor from each other Set a VOM meter to the ohm scale Connect the VOM test probes across the rotor winding previously disconnected from the rotor diode and capacitor Briggs Stratton Power P...

Страница 91: ...istor or capacitor fails and the winding is ok replace the diode assembly If the rotor tests are OK Re solder the three leads that were removed from the crimp and proceed to Test 5 Check Adjust Engine...

Страница 92: ...gine running at its correct no load speed Slowly turn the voltage adjust pot Figure 3 59 until no load voltage is 124VAC line to neutral or 248VAC line to line Units rated at 110 220 VAC With engine r...

Страница 93: ...ontrol circuit board These two components share the voltage regulation process See UNITS WITH POWER REGULATOR SYSTEM CONTROL CIRCUIT BOARD on page 39 Although the voltage regulation process is shared...

Страница 94: ...92 Section 3 Generator Diagnostics and Adjustments Portable Generator Familiarization Troubleshooting Guide...

Страница 95: ...prying Medium external snap ring pliers Available Service Kits Rotor Removal Kit Part 41079 Electronic Measuring Equipment The measuring equipment used in troubleshooting should be of industrial quali...

Страница 96: ...s well as problems with wiring connections Before continuing with the disassembly process visually inspect for the following Evidence of bearing failure Very fine metallic dust that generally accumula...

Страница 97: ...or housing from the plug Electrical Measurements NOTE Many of the electrical measurements that are necessary to accurately troubleshoot the Generac wound generator are accessible at this point In orde...

Страница 98: ...minal will slide out of the connector housing as shown in Figure 4 8 Repeat this process until all the terminals are removed from the connector housing When all of the terminals are free of the housin...

Страница 99: ...cks remove the four stator bolts that hold the rear bearing carrier and stator to the engine adapter Figure 4 13 With the stator bolts removed grip the rear bearing carrier and work it free from the r...

Страница 100: ...r keyway driving the rotor Very often removing the through bolt leaves the rotor attached to the tapered shaft This is due to heat of operation and the compression of the rotor bolt when it is properl...

Страница 101: ...he rotor bolt diameter is1 4 inch Use the 3 8 24 tap Figure 4 19 Item 4 to cut internal threads at the bearing end of the rotor shaft If the rotor shaft is 5 16 inch Use the7 16 20 tap Figure 4 19 Ite...

Страница 102: ...e appropriate thread pitch Figure 4 19 Item 1 or 2 into the threaded I D of the rotor shaft Tighten the capscrew firmly against the slotted end of the stud See Figure 4 23 Strike the head of the capsc...

Страница 103: ...otor Figure 4 25 Start the bolt into the threads of the tapered shaft by hand being careful not to crossthread the bolt Torque to specifications NOTE Torque specifications can be found in the appendix...

Страница 104: ...on the rear bearing carrier consists of a roll pin pressed into the inside flange Viewed from the outside of the carrier it would located at the 7 o clock position just inboard and slightly below the...

Страница 105: ...directly against the actual laminations of the stator without any gap inside the flange of the carrier Figure 4 33 All the alignment pins and notches should be in their proper orientation All the asse...

Страница 106: ...to ensure that nothing is internally bound grating or rubbing Assembling The Wiring Harness Install the protective mesh over the power wires as shown in Figure 4 36 NOTE Refer to the specific wiring...

Страница 107: ...ing the generator from resting in its cradle You should have retained two star washers and 1 wing nut from disassembly Install one star washer on the grounding lug Then the terminal lug for the ground...

Страница 108: ...as shown in Figure 4 42 and tighten screws finger tight Torque mounting screws Figure 4 43 to specifications in the torque chart found in the appendix of this guide Install Vibration Mounts to Cradle...

Страница 109: ...gure 4 46 Ensure that the louvers are up as shown Place the tab at the top of the cover over the grommet Install the cover with the screws you retained from disassembly Torque to specifications found...

Страница 110: ...108 Section 4 Generator Assemblies Portable Generator Familiarization Troubleshooting Guide...

Страница 111: ...g the access cover to the end of the sincro generator Figure 4 49 This exposes the components shown below in Figure 4 50 A visual inspection of this area can reveal both mechanical problems as well as...

Страница 112: ...rement locations are described in the section titled Troubleshooting Flow Chart For Sincro Wound Brushless Type Generators which begins on page 84 Removing The Capacitor Remove the capacitor from its...

Страница 113: ...e mounting stud breaks free before the nut It is ok to remove the nut and stud together With an assistant to help secure the complete unit a short block of wood and a large soft mallet Tap the stator...

Страница 114: ...ious failure or for rotor replacement Inspect for any loose debris obstructions or flaws on the engine adaptor stator laminations rear bearing carrier the threaded hole in the tapered shaft and the su...

Страница 115: ...e 4 62 Reinstall the grounding wire as shown in Figure 4 63 Remove the supporting blocks and seat the isolation mount studs through their holes in the cradle frame Install the nuts you retained from d...

Страница 116: ...ess cover with the louvered half down as shown in Figure 4 68 Reinstall access cover with the hardware you retained from disassembly Insure that there are no obstructions to the rotation of the rotor...

Страница 117: ...115 Section 4 Generator Assemblies Portable Generator Familiarization Troubleshooting Guide...

Страница 118: ...116 Section 4 Generator Assemblies Portable Generator Familiarization Troubleshooting Guide...

Страница 119: ...GENERAC TORQUE TABLE Appendix A Portable Generator Familiarization Troubleshooting Guide 117...

Страница 120: ...s Configuration NEMA 68868 22693 58888 74190 58889 L5 30P 5 15P L5 20P 6 15P 66883 26338 93568 58890 120 120 125 240 30 15 20 15 L5 30R 5 15R L5 20R 6 15R Receptacle No Plug Part No Volts Amps Configu...

Страница 121: ...bleshooting Guide Receptacle No Plug Part No Volts Amps Configuration NEMA 63025 68759 5 15P 5 20P 26338 120 120 15 20 5 15R DUPLEX 5 20R DUPLEX Receptacle No Plug Part No Volts Amps Configuration NEM...

Страница 122: ...of electricity CYCLE One complete reversal of alternating current of voltage from zero to a positive maximum to zero to a negative maximum back to zero The number of cycles per second is the frequency...

Страница 123: ...e current flows different in phase by 120 degrees from each other RATED SPEED Revolutions per minute at which the set is designed to operate RATED VOLTAGE The rated voltage of an engine generator set...

Страница 124: ...or potential difference expressed in volts VOLTAGE REGULATOR A component which automatically maintains proper generator voltage by controlling the amount of DC excitation to the rotor WATT Unit of el...

Страница 125: ...123 Appendix A Portable Generator Familiarization Troubleshooting Guide...

Страница 126: ...Appendix A Portable Generator Familiarization Troubleshooting Guide 124...

Страница 127: ......

Страница 128: ...re e W Wa as sh he er r F Fa am mi il li ia ar ri iz za at ti io on n T Tr ro ou ub bl le es sh ho oo ot ti in ng g G Gu ui id de e 1 19 90 02 27 75 5 H Ha an nd d H He el ld d G Ge en ne er ra at to...

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