Home

Bulletin

1. Potentiometer D Do notuse the Speed Potto check the overspeed shutdown setpoint See Figure 9 D Disconnect all loads from the generator when adjusting the overspeed cutout 1 Connect a frequency meter to the generator output 2 Turn Overspeed Pot counterclockwise to max overspeed cut out point See Figure 10 OVERSPEED D Figure 1Q Overspeed Potentiometer 3 While observing the frequency meter manually turn the governor actuator shaft until frequency reaches the desired cut outspeed NOTE Do notexceed 72 Hertz 4 While keeping the generator at the desired cut n speed slowly turn Overspeed Potclockwise until unit shuts down See Figure 11 OVERSPEED Figure 11 Overspeed Potentiometer NOTE If Overspeed Potis adjusted too low the engine may shut down on startup because of governor overshoot SB 555 56 Condition Fault Result Loss of pickup while running Throtte moves to closed position and fuel shut off solenoid de energizes Genset shutdown Engine overspeed Fuel shut off solenoid de energizes Genset shutdown Break of fuel shut off solenoid lead Fuel shut off solenoid de energizes Loss of DC power to governor assembly Fuel shut off solenoid de energizes Genset shutdown Break of stepper motor leads Erratic performance then fuel shut off solenoid de energizes Genset shutdown Actuator linkage failure Erratic performance then fuel
2. shut off solenoid de energizes Genset shutdown Figure 12 Electronic Governor Fault Shutdown Conditions and Results OOOO OOOO OUTO CIGIGNED Cove GOVERNOR ACTUATOR J4 16 gt 17 9 gt 10 GOVERNOR CONTROL MAGNETIC PICKUP Schematic O S GAIN SPEED TP 5572 6 GOVERNOR ya e YELLOW ELECTRONIC GOVERNOR BOARD OVER GAIN SPEED SPEED STEPPER MAGNETIC MOTOR PICKUP SENSOR Figure 14 Schematic Symbols Typical SB 555 56
3. G Setscrew 7 Open throttle Figure 5 Actuator Stepper Vbtor lea O RED WHT BLU TP 5572 6 Figure G Actuator Coil Group SB 555 56 Governor Control The electronic control board provides power to the actuator Italso controls energizing and de energizing of the fuel anti diesel AD solenoid or gas valve Prior to any governor adjustments 1 Open the line circuit breaker between the generator and any loads which may be frequency sensitive 2 Connect a frequency meter to the generator AC output in order to monitor AC output while making adjustments Speed Adjustment Turn speed potentiometer clockwise to increase speed counterclockwise to decrease speed See Figure 7 OREx Sa OVER SPEED GAIN SPEED Q w oO 4 OREP 4Pole Generators 60Hz 1800RPM 5OHz 1500RPM Figure 7 Speed Potentiometer SB 555 56 Gain Adjustment The Gain Potentiometer Pot pertains to governor sensitivity See Figure amp TP 5572 6 Figure amp Gain Potentiometer D Mbve Gain Potin 1 8turn increments if hunting or surging occurs D Changing the Gain Pot setting may affect the governor Speed Pot D Governor Speed Pot adjustment will not affect the Gain Pot Overspeed Adjustment The governor control contains a circuit which will de energize the carburetor fuel solenoid AD if the generator exceeds the overspeed setting SPEED Figure Q Speed
4. SB 5F ECE SERVICE BULLETIN Original Issue Date 596 Model and G amp RIW 4 SCK WICKIVR 4CFKIVICFKIVR 7CCKIMCCKIVR 7CCFKIMICCFKNR Market RV Mbbile and Small Standby Subject Kohler Electronic Governor 0 2786 O Troubleshooting Kohler Generator Division in an attemptto reduce returns of functional electronic governors created this bulletin to better inform customers Consult the Service Manual for adjustment procedures not found in this bulletin Service Manual Publication Number Mbdel 4ASCKMCKIVR ACFKMCFKIVR TP 5394 7CCKMCCKIVR 7CCFKMCCFKIVR 6G SRY TP 5570 TP 5632 Figure 1 Service Manual Selection OVER SPEED GAIN SPEED Figure 2 Kohler Electronic Governor Control A WARNING 2 ke gt POY Accidental starting Can cause severe injury or death Disconnect battery cables before working on generator set disconnect negative lead first and reconnectit last Disabling generator set Accidental starting can cause severe injury or death Disconnect battery cables remove negative lead firstand reconnectitlast to disable generator setbefore working on the generator set or connected equipment The generator set can be started by the remote startStop switch unless this precaution is followed Service Sales Parts Technician Technician Technician Return Routing i 4 ne No 1 No 2 No 3 This to Initial Here A WARNING Hazardous voltage Mbving rotor Can cause se
5. state speed regulation of O25 The factory sets the electronic governor and the governor usually requires no further adjustment Ifthe unitoperates erratically check the following items before readjustment D Check the carburetor for dirt grime or misadjustment Also check the idle adjustment screw The screw should notprevent the throttle plate from completely closing Also check the throttle linkage for any binding dirt damage etc D Check electrical connections check the stepper motor controller box and governor connector inside the controller for clean and tight connections D Check electrical ground connections a good DC ground must be provided to the controller assembly and governor circuit D Check fora good positive 12volt DC supply Also check if the positive voltage supply is unstable or below Svolts DC making the control unit function erratically D Check magnetic pickup connections Poor connections may cause the signal to be erratic As long as this erratic signalis being sent the unit will not shut down due to loss of pickup D Check for dirt buildup on magnetic pickup metal filings or caked on dirt rease may decrease the output signal of the magnetic pickup D Check for a loose coupling screw D Check for stepper motorAhrottle shaft coupling wear f the roll pin wore the slot of the stepper motor coupling loosen coupling screw and move coupling so thatroll pin is positioned ata pointin s
6. t Actuator should initially move clockwise wide open throttle and then turn completely counterclockwise The actuator should remain in this position Stop generatorset Ifactuator fails this test replace actuator The governor actuator should function with steady and smooth movement during operation If movement of actuator is erratic or large changes in movement occur D Check shaft alignment ensure that the actuator and throttle shafts are concentric and that the throttle shaftpin is atmidpointof the actuator slot D Check for excessive coupling slot wear replace worn parts D Check for broken or loose wiring including plug connections Adjust coupling so throttle shaft pin is recessed to the middle of the slot Stepper motor rotational position adjustment is not necessary Throttle plate position can be either open or closed during assembly Only two actuator leads of each coil group are utilized BLK YEL and RED WHT Resistance per phase 385 ohms Voltage pulses received from the governor control determine movement of the stepper motor NOTE A 12 VDC voltage applied to the motorleads will resultin a single step movement of 1 8 Reversal of the voltage polarity will result in a 1 8 movement in the reverse direction NOTE The stepper motor will notcontinuously rotate with battery voltage supplied to its windings TOP VIEW 1 Actuator 2 Coupling 3 Closed throttle 4 Intake air flow 5 Pin
7. tepper motor coupling without wear Tighten coupling screw SB 555 56 Magnetic Pickup See Figure 3or Figure 4 The magnetic pickup provides an AC signal to the control unit Mnimum voltage output from the pickup during engine cranking should be 1 75 VAC Air Gap See Figure 3or Figure 4 The air gap between the ring gear and pickup should be OQ O4Oinches NOTE Measure the air gap at 3or 4places to get an accurate reading To adjust air gap loosen the locknut and turn pickup clockwise until it justbottoms on the ring gear then back out 34turns Hold pickup in this position while retightening locknut If loss of signal or failure of the pickup occurs while running the governor control will de energize the carburetor shut off solenoid to stop the engine SB 555 56 1 QO4in air gap 2 Top of flywheel ring gear tooth 3 Magnetic pickup generates an AC voltage 4 Locknut Figure 3 Magnetic Pickup Air Gap 4 5CKMCKIVR and GRM 1 Ignition coil 2 Magnetic pickup Figure 4 Magnetic Pickup 7CCK MCCK MNR Actuator See Figure 5and Figure The actuator consists of a stepper motor coupled to the carburetor throttle shaft It receives signals from the governor control unit and rotates the shaft to the proper position To test for proper operation of the actuator disconnect magnetic pickup leads Manually move the throttle shaftgovernor stepper motor fully counterclockwise Closed throttle Start generator se
8. vere injury or death Operate generator set only with all guards and electrical enclosures in place Grounding generator set Hazardous voltage can cause severe injury or death Electrocution is possible whenever electricity is present Open main circuit breakers ofall power sources before servicing equipment Configure the installation to electrically ground the generator set and electrical circuits when in use Never contact electrical leads or appliances when standing in water or on wet ground as the chance of electrocution is increased under such conditions A WARNING Rotating parts Can cause severe injury or death Do not operate generator set without all guards screens and covers in place Exposed moving parts can cause severe injury or death Keep hands feet hair and clothing away from belts and pulleys when unit is running Replace guards covers and screens before operating generator set The governor system consists of an electronic isochronous governor an electro mechanical stepper motor and a magnetic pickup Electrical pulses are supplied by the magnetic pickup to the isochronous governor control unit each time one of the ring gear teeth passes the pickup The control unit compares the frequency of these pulses to a preset reference and provides a signal to the stepper motor which controls the carburetor throttle position and the engine speed This is a closed4toop system and typically provides steady

Bulletin

Contents

Download Pdf Manuals

Related Search

Related Contents