Onan Mobile GenSet User manual

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982-0001
9-2002

Safety Precautions
The following symbols in this manualhighlight condi-
tions potentially dangerous to service personnel, or
equipment. Read this manual carefully. Know when
these conditions can exist. Then take necessarysteps
to protectpersonnelas well as equipment.
Thissymbol if usedwarnsof imme-
diate hazards which will result in
severepersonal injury or death.
1-1 This symbol refers to a hazard or
unsafepractice whichcanresult in
severepersonal injury ordeath.
This symbol refers to a.hazard or
unsafe practice whichcan result in
personal injury or product orproperty damage.
PROTECTAGAINST MOVING PARTS
Avoid moving parts of the unit. Avoid use of loose
jackets, shirts or sleeves due to danger of becoming
caught inmovingparts.
Make sure all nuts and bolts are secure. Keep power
shields and guards in position.
Ifyoumustmakeadjustmentswhiletheunitisrunning,
use extreme caution around hot manifolds, moving
parts,etc.
Do notwork onthis equipment when mentallyor physi-
callyfdigued.
GUARD AGAINST ELECTRICSHOCK
Disconnectelectric power before removing protective
shields or touching electrical equipment. Use rubber
insulative mats placed on dry wood platforms over
floorsthataremetalorconcretewhenaroundelectrical
equipment.Donotweardampclothing(particularlywet
shoes)orallowskinsurfaces
to bedampwhenhandling
electricalequipment.
Disconnectbatteriesto preventaccidentalenginestart.
Jewelryisagoodconductorofelectricityandshouldbe
removedbeforeworkingonelectricalequipment.
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Use extremecaution when working on electricalcom-
ponents.Highvoltagescause injury or death.
1
Followallstateand localcodes.To avoidpossibleper-
sonal injury or equipment damage, a qualified electri-
cian or an authorizedservice representativemust per-
form installationandall service.
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EXHAUST GAS IS DEADLY!
Exhaustgasescontaincarbonmonoxide, anodorlessandcolorlessgas formed
duringthecombustionof hydrocarbonfuels. Carbonmonoxideispoisonousand
cancauseunconsciousnessanddeath. Symptomsof carbonmonoxidepoisoning
are the following:
0 Inabilityto Think Coherently 0 Dizziness
0 Vomiting Headache
0 Muscular Twitching Weaknessand Sleepiness
0 Throbbing in Temples
If you oranyoneelseexperienceany
of thesesymptoms, shut downtheunitand
getoutintothefreshairimmediately.Ifsymptomspersist,seekmedicalattention.
DO NOT OPERATE THE UNIT UNTILIT HAS BEEN INSPECTEDAND REPAIRED.
Thebestprotectionagainstcarbonmonoxideinhalationisproperinstallationand
regular,frequentvisualandaudibleinspectionsof thecompleteexhaustsystem.
Redistribution or publication of this document, 
by any means, is strictly prohibited.

Table of Contents
TITLE PAGE
SAFETY PRECAUTIONS ................................................................. InsideFrontCover
About this Manual
.................................................................................. i -I
Test Equipment .................................................................................... i -I
How to ObtainService .............................................................................. i -I
ControllerDescriptions ...................................... : ....................................... i-2
Control Descriptions ................................................................................ 2-1
Control PanelInterior ............................................................................... 2-2
1 Voltage Regulator ................................................................................ 2-2
CurrentTransformers ............................................................................. 2-5
Control Heater ................................................................................... 2-6
Control Descriptions ................................................................................ 3-1
Control PanelInterior ............................................................................... 3-4
EngineControl Monitor 3-4
Run Relay ....................................................................................... 3-6
InterfaceRelay Modules. .......................................................................... 3-7
Time Delayed'Start/Stopand PreheatModule ....................................................... 3-8
I MagneticPickup InterfaceModule 3-9
Over/Under Voltage Sensor Module ............................................................... 3-10
Operation ......................................................................................... 3-11
. StartingSequence ............................................................................... 3-12
Starter-Disconnect Parameters ................................................................... 3-12 .
Start-DisconnectSequence ...................................................................... 3-12
I
NormalOperating Parameters .................................................................... 3-12
~ StoppingSequence .............................................................................. 3-13
EmergencyShutdown ............................................................................ 3-13
I ENGINECONTROLSERVICE 4-1
Troubleshooting .................................................................................... 4-1
Engine Does Not Crank ........................................................................... 4-2
EngineCranks But Does Not Start .................................................................. 4-3
EngineStarts ButStopsAfter RunningSeveralSeconds .............................................. 4-5
Engine-Generator Is In Operation. Then a FaultShutdownOccurs ..................................... 4-7
Tests ............................................................................................... 4-8
Battery Checkout ................................................................................. 4-8
Battery CableCheckout ........................................................................... 4-8
Alternator Checkout .............................................................................. 4-8
SolenoidCheckout ............................................................................... 4-8
RelayCheckout .................................................................................. 4-8
FuelSolenoidCheckout ........................................................................... 4-8
ControlSwitch Checkout .......................................................................... 4-8
.
INTRODUCTION ..................................................................................... 1-1
AC CONTROL 2-1
.......................................................................................
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i DCCONTROL ....................................................................................... 3-1
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WIRING DIAGRAMS .................................................................................. 5-1
ENGINESENSOR LOCATIONS ........................................................................ 6-1
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Section 1 Introduction
ABOUT THIS MANUAL
Thismanualprovidesbasicinformationregardingyour
Onan GenSet AC/DC control options, internalcompo-
nentdescriptions,and DC controltroubleshooting. For
theAC controltroubleshooting,refertospecificgenera-
tor service manual. For more DC servicing/trouble-
shooting referto specific engineservicemanual.
Study all manuals carefully and observe all warnings
and cautions. Knowing your generator set, using it
properly,andfollowingaregularmaintenanceschedule
can result in longer unit life, better performance, and
safer operation.
Informationfor printedcircuit boardrepairisnotexten-
sive because solid state printed circuit boards lend
themselves more to replacementthan repair.Applica-
tion
of meters or hot soldering irons to printed circuit
boards by other than qualified personnel can cause
unneGessary and expensive damage. Repair of the
printedcircuit boards is not recommended.
High voltagetestingor highpotential
(or Megder) testing of generator
windings cae cause damage to solid state compo-
nents. Isolate these componentsbefore testing.
TEST EQUIPMENT
Mostof the test proceduresinthis manual can be per-
formed with an AC-DC multimeter such as a Simpson
Model
260 VOM or a digital VOM. Some other instru-
mentsto have availableare:
Onan Multitester
Jumper Loads
0 Onan Load Test Panel
0 AC Voltmeter
DC Voltmeter
See Tool Catalog 900-001 9
HOW TO OBTAINSERVICE
Ifthegeneratorset/controis requiresservicingbeyond
thescopeofinformationgiveninthismanual,contactan
Onan Distributorfor assistance. Onan factory trained
Partsand Service representativesare readyto handle
all your serviceneeds.
When contacting an Onan Distributor, always supply
the complete model number and serial number as
shownonthe Onannameplate.The Onan nameplateis
locatedonthesideof thegeneratorcontrolbox(Figure
1-1).
Incorrect service or replacement of
l5iEWEl parts can result in severe personal
injury and/or equipment damage. Service personnel
must bequalifiedtoperformelectricaland/ormechan-
ical service.
W Serial NO. W
I
M-1641
FIGURE 1-1. ONAN NAMEPLATE
1 -1
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by any means, is strictly prohibited.

CONTROLLER DESCRIPTIONS
The control configurations have been designed to
accommodateboththeverticalandhorizontalstylecon-
trolcompartments.Althoughthecontrolsontheexterior
ofthecabinetsaresimilar,theinteriorcomponentloca-
tions differsomewhat.Refertothe Figure
3-2 for exact
componentlocationsof your control cabinet.
The control cabinet is separated into a DC panel for
engine-relatedcomponentsontherightside,andanAC
panelforgenerator-relatedcomponentsontheleftside.
Dependingon optionsordered,thecontrolgroupscan
consist of the standard model Detector
2 DC control
panelorwithoptionsasaDetector
12 controlpanel(can
also includeDetectorAC metercontrol panel). Thefol-
lowing brieflydescribes each.
Detector 2 Group
This isthestandard modelDC control,whichoffersthe
minimumfeatures requiredto operate and monitorthe
generator set. Its name refersto the two DC operating
'ndicatorlamps:
0 The green RUN lamp, which lights when unit is
operating.
0 The red FAULT lamp which lights in the event of
shutdown
for a low oil pressure,highenginetemper-
ature, overcranking,or overspeedcondition.
Detector 12 Group
This modelDC control group includesoptionsto more
effectively monitor the generator set during operation
and identifythe cause of a shutdown. It also includes
pre-alarmmonitoringto informtheoperatorthatashut-
downcircumstancemightoccurifattentionisnotgiven
to an aspectof engineoperation soon.
Detector AC Group
This AC control group enables generator monitoring
andcontrolatthegensetandconsistsof meters, phase
selector, and voltageadjustment.
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AC PANEL DC PANEL
-
0
Q
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FIGURE 1-2. STANDARDMODEL DETECTOR 2
WITH NO OPTIONS
AC PANEL DCPANEL
.-
z
FIGURE 1-3. VERTICALCONTROL, COMPLETEWITH
DETECTOR
12 AND DETECTORAC OPTIONS
M-1590-2
1
M-1590-1
1-2
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Section 2, AC Control
CONTROL DESCRIPTIONS
ThefollowingdescribestheoptionalDetectorAC meter
packageforon-setcontrolandmonitoringofthegener-
ator.
AC Voltmeter: Dualrangeinstrumentindicatinggenera-
tor AC voltage. Measurementrange in use shown on
indicatorlight.
AC Ammeter: Dualrangeinstrumentindicatinggenera-
tor AC voltage. Measurement range in use shown on
indicator
I ight.
FrequencyMeter: Indicatesgeneratoroutputfrequency
in hertz. It can be used to check engine speed (Each
hertzequals
30 r/minfor 1800 r/min generatorsets, 60
r/minfor 3600 r/min generatorsets.)
Waffmefer:Continuously givesreading
of thegenerator
output inkilowatts.
VoltageAdjust: Rheostatprovidingapproximatelyplus
or minus five percent adjustment of the rated output
voltage.
FieldBreaker: Providesgeneratorexciterandregulator
protectionfromoverheatingintheevent
of certainfail-
ure modes of generator,exciterand voltage regulator.
Phase Selector Switch: Selects phases of generator
outputtobemeasuredbyACvoltmeterandAC ammeter.
Upper and Lower Scale Indicator Lights: Indicates
which scaleto use on the AC voltmeterand ammeter.
UPPERAND
LOWERSCALE
INDICATORLAMPS PHASESELECTOR
SWITCH
VOLTAGE
ADJUSTING
RHEOSTAT
\ /
\
DUALRANGE
AC VOLTMETER
FREQUENCY
METER
FIELD
BREAKER
0
WATTMETER
" -
AC PANEL
/
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DC PANEL
M-1590-1
FIGURE 2-1. AC CONTROLS
2-1
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by any means, is strictly prohibited.

CONTROL PANEL INTERIOR
The following describesthe internal componentsand
their function. Refertotheappropriategeneratorconnectiondiagram
toidentifytheoutputleadsthatmustberoutedthrough
each current transformer. DeDendinn on model of
Voltage Regulator
Because the voltage regulator circuit is directly con-
nected
to theAC generator, and because it does
lateexcitationinresponseto generatoroutput,thisser-
vice informationiscoveredwithgeneratorservice. See
the generatorservicemanualfor the voltage regulator
information. two primaryturns.
generatorset,
it mayberequiredtorouiethegenerator
outputleadsthroughthecurrenttransformersasecond
or third winding to accomplishproperamplificationfor
accurate meter movement readings. An output wire
passing through a current transformer is considered
onePrimaVtUrn.If passedthroughagain,thatwouldbe
Current Transformers
Forgeneratorsetsequippedwiththeoptionalammeter,
the generator output leads must be routedthroughthe
current trar;sfor,mers
for proper meter operation. See
Figure
2-2. The current transformersare identifiedas
CT21,CT22,etc.ontheAC wiringdiagramsandelectri-
.
' cal schematics.
OUTPUTWIRE
I)_ FROM GENERATOR
CURRENT
TRANSFORMER
Ld
TWO PRIMARY TURNS
CURRENT TRANSFORMERS
CURB
TRANSFl
U
ONE PRIMARY TURN
ES-1566
FIGURE 2-2 CURRENTTRANSFORMERS
2-2
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by any means, is strictly prohibited.

Control Heafer
A controlheaterprovides a meansofhumidity/tempera-
ture control
of the control box interior to protect the
components and ensuretheir effectivenessvJhen the
generatorset is subjectedtovaryingambientaircondi-
tions during extendedperiods
of non-use(Figure 2-3).
The elementiscontrolledbyan adjustablethermostat.
\
TO 120 VAC
SUPPLY
HEATER
ELEMENT
FIGURE 2-3. CONTROL HEATER
2-3
ES-1563-3
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Section 3. DC Control
CONTROL DESCRIPTIONS
The following function and operation descriptions
includesoptions. Refertothoseapplicabletoyour spe-
cific controlgroup. See Figure
3-1.
OilPressure Gauge: Indicatespressure of lubricating
oil in engine (wired to a sensor unit located on the
engine).
Water Temperature Gauge: Indicates temperature of
circulating coolant in engine (wired to a sensor unit
locatedon the engine.
BatteryChargeRateDCAmmeter: Indicatesthebattery
charging current.
OilTemperatureGauge:Indicates temperatureof lubri-
catingoilinengine(wiredtoasensorunitlocatedonthe
engine).
Tachometer: Provides constant monitoring of engine
r/min.
Speed
Adjust Potentiometer: Operator control for
adjusting engine r/min (used with electronicgovernor
only).
Run-Stop-Remote Switch: Starts and stops the unit
locally, or from a remote location wired to the control
enginemonitor board.
Reset, LampTest, PanelLampSwitch: Resetsthefault
circuitonlywhenthe Run-Stop-Remoteswitchisinthe
Stop (Reset) position. Tests fault lamps (except
2 light
control)and turns on the control panel lamp.
Preheat Switch: Used with diesel engines to provide
momentary warm-up of glow plugs.
Running Time Meter: Registers the total number of
hoursthat the unit has run. Use itto keepa recordfor
periodicservicing.Time iscumulative;meter cannot be
reset.
ControlPanelLamp: Conveniencelightfor operator.
lndicator Lamps: Refer to the following control group
descriptions.
Detector 2 Control
The standard control panel has two monitor system
indicatorlamps.
ThegreenRUNlampcomesonassoonasbothprimary
and secondary starter disconnect circuits are opened
after unit starting. The red FAULT lamp will come on
when-an emergency shutdown of the generator set
occursfrom oneof thefollowing conditions:
0 Low oil pressureduring unitoperation
0 Highenginetemperature during unitoperation
0 Overspeedof engineduring unitoperation
0 Overcrankconditionduring starting
Detector 12 Control
The twelve monitor system option features indicator
lampsfor thefollowing:
0 RUN (green) lamp comes on when both starter dis-
connectcircuits are opened after unitstarting.
0 PRE LO OIL PRES(yellow)indicatesengineoil pres-
sure is marginallylow.
0 PREHIENGTEMP(yellow)indicatesenginetemper-
ature is marginallyhigh.
0 LO OIL PRES (red)indicatesengine has shut down
becauseof critically low oil pressure;
0 HI ENG TEMP (red)indicatesengine has shut down
becauseof critically hightemperature.
0 OVERSPEED (red) indicates engine has shut down
becauseof excessivespeed.
0 OVERCRANK (red) indicates the starter has been
lockedout becauseof excessivecrankingtime.
0 FAULT 1 (red)anundedicatedfault. Mightbefactory
programmedasashutdownornon-shutdown,andas
atimedornon-timedfault.(Normallysetfortimedshut-
down.)
0 FAULT 2 (red)samefeaturesas Fault 1. (Normallyset
for immediateshutdown.)
0 LO ENG TEMP (yellow) enginetemperatureismar-
ginally lowfor starting.Indicatesinoperativecoolant
heater.
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0 LOFUEL (yellow) indicates fuel supply is margi-
0 SWITCHOFF(flashingred)indicatesgeneratorsetis
nallylow.
not
in automatic startoperationmode.
0 RUN(green)
0 FAULT(red)
3-1
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