Guardian QT048 User manual

QT048
GENERAC 4.2L ENGINE
• Allinputconnectionsinonesinglearea
• Highcoolanttemperatureshutdown
• Lowoilpressureshutdown
• Lowcoolantlevelautomaticshutdown
• Overspeedautomaticshutdown
• Cranktimer
• Exercisetimer
• Oildrainextension
• Coolflowradiator
• Closedcoolantrecoverysystem
• UV/Ozoneresistanthoses
• Watertightstateoftheartelectricalconnectors
• Mainlinecircuitbreaker
• Radiatordrainextension
• Batterychargealternator
• 2Ampstaticbatterycharger
• Batterycables
• Batteryrack
• Fanandbeltguards
• Isochronousgovernor
• Flexfuelline
• Hourmeter
STANDARD EQUIPMENT
Liquid Cooled Gas Engine Generator Sets
Standby Power Rating
48 kW 60 Hz
Naturally Aspirated
Gaseous Fueled
• Innovativedesignandfullyprototypetested
• UL2200Listed
• Solidstatefrequencycompensated
 voltageregulator
• Dynamicandstaticbatterycharger
• Soundattenuatedacousticallydesignedenclosure
• Quiettestforlownoiselevelexercise
• Acousticallydesignedenginecoolingsystem
• Highflowlownoisefactoryengineeredexhaustsystem
• State of the art digital control system with R100 digital
controlpanel
• Watertightelectricalconnectors
• Rodentproofconstruction
• High efficiency, low distortion Generac designed
alternator
• Vibrationisolatedfrommountingbase
• Matching Generac transfer switches engineered and
testedtoworkasasystem
• Allcomponentseasilyaccessibleformaintenance
• Electrostaticallyappliedpowderpaint
FEATURES

APPLICATION
& ENGINEERING DATA
Rating definitions - Standby: Applicable for supplying emergency power for the duration of the utility power outage. No overload capability is available for this rating. (All ratings in accordance with
BS5514, ISO3046 and DIN6271). (All ratings in accordance with BS5514, ISO3046, ISO8528 and DIN6271).
QT048
GENERATOR SPECIFICATIONS
TYPE ...........................................................................................................Synchronous
ROTOR INSULATION..........................................................................................Class H
STATOR INSULATION.........................................................................................Class H
TOTAL HARMONIC DISTORTION........................................................................... <5%
TELEPHONE INTERFERENCE FACTOR (TIF) ........................................................<50
ALTERNATOR OUTPUT LEADS 3 PHASE ........................................................... 4 wire
BEARINGS.................................................................................................... Sealed Ball
COUPLING.................................................................................................. Flexible Disc
LOAD CAPACITY (STANDBY RATING) ................................................................ 48 kW
EXCITATION SYSTEM........................................................................................... Direct
NOTE: Generator rating and performance in accordance with
ISO8528-5, BS5514, SAE J1349, ISO3046, and DIN6271 standards.
GENERATOR FEATURES
Revolving field heavy duty generator
Directly connected to the engine
Operating temperature rise 120 °C above a 40 °C ambient
Insulation is Class H rated at 150 °C rise
All models are fully prototyped tested
VOLTAGE REGULATOR
TYPE ................................................................................................................Electronic
SENSING ................................................................................................... Single Phase
REGULATION.......................................................................................................... ± 1%
FEATURES............................................................................................... V/F Adjustable
Adjustable Voltage and Gain
LED Indicators
CONTROL PANEL FEATURES
SEVEN LED INDICATOR LIGHTS ADDITIONAL FUNCTIONS
  •Systemready •Utilitysensing
  •Lowfuelpressure •Delayonutilityfailureforenginestart
  •Lowbattery •Enginewarm-upbeforetransfer
  •Lowoilpressure •Delaytoretransfertoutility
  •Highcoolanttemp/lowcoolanttemp •Enginecooldowntimer
  •Overspeed •Exercisernotset
  •Overcrank •Hourmeter
INTERNAL FUNCTIONS:
•3 position switch (auto, off and manual)
  •2wirestartforanytransferswitch
  •CommunicateswiththeGeneracRTStransferswitch
  •Built-in7dayexerciser
  •Selectableenginespeedatexercise
  •Governorcontrollerisbuiltintothemastercontrolboard
  •Temperaturerange-40°C to 70 °C
ENGINE SPECIFICATIONS
MAKE ................................................................................................................ Generac
MODEL........................................................................................................................ V6
CYLINDERS...................................................................................................................6
DISPLACEMENT.................................................................................................4.2 Liter
BORE (inches) ..........................................................................................................3.81
STROKE (inches)......................................................................................................3.74
COMPRESSION RATIO...........................................................................................9.3:1
INTAKE AIR SYSTEM ....................................................................... Naturally Aspirated
VALVE SEATS (Int. & Exh.) ........................................... Precision ground and hardened
LIFTER TYPE........................................................................................ Roller, Hydraulic
GOVERNOR SPECIFICATIONS
TYPE ................................................................................................................Electronic
FREQUENCY REGULATION....................................................................... Isochronous
STEADY STATE REGULATION.......................................................................... ± 0.25%
ENGINE LUBRICATION SYSTEM
OIL PUMP ................................................................................................................Gear
OIL FILTER............................................................................. Full flow spin-on cartridge
CRANKCASE CAPACITY...................................................................................6 Quarts
ENGINE COOLING SYSTEM
TYPE ................................................................................................ Pressurized Closed
WATER PUMP FLOW .................................................................................. 10.8 gal/min
FAN SPEED .............................................................................................................1050
FAN DIAMETER............................................................................................... 22 inches
FAN MODE..............................................................................................................Puller
FUEL SYSTEM
FUEL TYPE .......................................................................... Natural gas, propane vapor
CARBURETOR...............................................................................................Down Draft
SECONDARY FUEL REGULATOR................................................................... Standard
FUEL SHUT OFF SOLENOID .......................................................................... Standard
OPERATING FUEL PRESSURE..................................................................5” - 14” H2O
ELECTRICAL SYSTEM
BATTERY CHARGE ALTERNATOR.............................................................12V 30 Amp
STATIC BATTERY CHARGER .............................................................................. 2 Amp
RECOMMENDED BATTERY .......................................................... Group 24F, 525CCA
SYSTEM VOLTAGE............................................................................................. 12 Volts

OPERATING DATA
QT048
RATING: Allthreephaseunitsareratedat0.8powerfactor.Allsinglephaseunitsareratedat1.0powerfactor.STANDBYRATING:Standbyratings
applytoinstallationsservedbyareliableutilitysource.Thestandbyratingisapplicabletovaryingloadsforthedurationofapoweroutage.Thereis
nooverloadcapabilityforthisrating.RatingsareinaccordancewithISO-3046-1,BS5514,andDIN6271.Maximumwattageandcurrentaresubject
toandlimitedbysuchfactorsasfuelBtucontent,ambienttemperature,altitude,enginepowerandcondition.Designandspecificationsaresubject
tochangewithoutnotice.
KWratingisbasedonLPGFuelandmayderatewithnaturalgas.
QT048
kW RATING 48
ENGINE SIZE 4.2LiterV6
GENERATOR OUTPUT VOLTAGE/KW - 60Hz kW - LP Amps kW - NG Amps CB Size
120/208V,3-phase,0.8pf 48 166 46 160 175
120/240V,3-phase,0.8pf 48 144 46 138 150
277/480V,3-phase,0.8pf 48 72 46 69 80
GENERATOR LOCKED ROTOR KVA
AVAILABLE @ VOLTAGE DIP OF 35%
Singlephaseor2083-phase 100
480V3-phase 110
ENGINE FUEL CONSUMPTION (Natural Gas) (Propane) Natural Gas Propane
(ft3/hr.) (gal/hr.) cuft/hr
Exercisecycle 88 0.94 34.4
25%ofratedload 205 2.23 81
50%ofratedload 370 4.03 147
75%ofratedload 516 5.62 204
100%ofratedload 661 7.20 261
ENGINE COOLING
Airflow (inlet air including alternator and combustion air) ft3/min. 2,460
Systemcoolantcapacity USgal. 3.0
Heatrejectiontocoolant BTU/hr. 165,000
Max.operatingairtemp.onradiator °C(°F) 60(150)
Max.ambienttemperature °C(°F) 50(140)
COMBUSTION AIR REQUIREMENTS
Flowatratedpower60Hz cfm 235
SOUND EMISSIONS IN DBA
Exercisingat7meters 60
Normaloperationat7meters 65
EXHAUST
Exhaustflowatratedoutput60Hz cfm 395
Exhausttemp.atmuffleroutlet °F 1100
ENGINE PARAMETERS
RatedsynchronousRPM 60Hz 1800
HPatratedKW 60Hz 75
POWER ADJUSTMENT FOR AMBIENT CONDITIONS
TemperatureDeration
3%forevery10°Cabove-°C 25
1.65%forevery10°Fabove-°F 77
AltitudeDeration
1%forevery100mabove-m 183
3%forevery1000ft.above-ft. 600

QT048
INTERCONNECTIONS
48/46 240 1Ø200 #6 to 300 mcm
48/46 208 3Ø 175 #6 to 300 mcm
48/46 240 3Ø 150 #6 to 300 mcm
48/46 480 3Ø 80 #6 to 300 mcm
INSTALLATION LAYOUT
InstallationDrawingRef.No.0G5868
Generac Power Systems, Inc. • P.O. Box 8, Waukesha, WI 53187 • generac.com
©2008 Generac Power Systems, Inc. All rights reserved. All specifications are subject to change without notice. Bulletin 0179270SBY/Printed in U.S.A. 09.08
WEIGHT: 1740 lbs.