Generac SG020 User Manual

SG020
SG025

Standby Power Rating

20KW 60 Hz
25KW 60 Hz

Liquid Cooled Gas Engine Generator Sets

Power Matched

GENERAC MMC 4G15 ENGINE

Naturally Aspirated

FEATURES

■ INNOVATIV E DESIGN & PROTOTYPE TESTING are key
components of GENERAC'S success in "IMPROVING POWER BY
DESIGN." But it doesn't stop there. Total commitment to component
testing, reliability testing, environmental testing, destruction and life
testing, plus testing to applicable CSA, NEMA, EGSA, and other
standards, allows you to choose GENERAC POWER SYSTEMS
with the confidence that these systems will provide superior
performance.

■ TEST CRITERIA:

✓ PROTOTYPE TESTED

✓ SYSTEM TORSIONAL TESTED

✓ ELECTRO-MAGNETIC INTERFERENCE

✓ NEMA MG1 EVALUATION

✓ MOTOR STARTING ABILITY

✓ SHORT CIRCUIT TESTING

✓ UL 2200 COMPLIANCE AVAILABLE

■ SOLID-STATE, FREQU EN CY COMPENSATED VOLTAGE
REGULATION. This state-of-the-art power maximizing regulation

system is standard on all Generac models. It provides optimized
FAST RESPONSE to changing load conditions and MAXIMUM
MOTOR STARTING CAPABILITY by electronically torque-matching
the surge loads to the engine.

■ SINGLE SOURCE SERVICE RESPONSE from Generac's dealer
network provides parts and service know-how for the entire unit,
from the engine to the smallest electronic component. You are never
on your own when you own a GENERAC POWER SYSTEM.

■ GEN ERAC TRANS FER SWITC HES, SWITC HGEAR AND
ACCESSORIES. Long life and reliability is synonymous with

GENERAC POWER SYSTEMS. One reason for this confidence is
that the GENERAC product line includes its own transfer systems,
accessories, switchgear and controls for total system compatibility.

APPLICATION
& ENGINEERING DATA

SG020 / SG025

GENERATOR SPECIFICATIONS

TYPE ................................................................. Two-pole, revolving field

ROTOR INSULATION ..................................................................Class F

STATOR INSULATION .................................................................Class F

TOTAL HARMONIC DISTORTION ..................................................

TELEPHONE INTERFERENCE FACTOR (TIF) ................................

ALTERNATOR ...........................................Self-ventilated and drip-proof

BEARINGS (PRE-LUBED & SEALED) .................................................1

COUPLING .............................................................. Direct, Flexible Disc

LOAD CAPACITY (STANDBY) .......................................................100%

NOTE: Emergency loading in compliance with NFPA 99, NFPA
110, paragraph 5-13.2.6. Generator rating and performance in
accordance with ISO8528-5, BS5514, SAE J1349, ISO3046 and
DIN6271 standards.

EXCITATION SYSTEM

DIRECT ............................................................. DC excitation system ✓

Low-velocity brushes and slip rings ✓

REGULATION ................................................................... Solid-state ✓

.................................................................................... +2% regulation ✓

<3%

<50

GENERATOR FEATURES

ENGINE SPECIFICATIONS

MAKE .................................................................................... GENERAC

MODEL ................................................................................. MMC 4G15

CYLINDERS ............................................................................... 4 in-line

DISPLACEMENT ................................................... 1.5 Liter (91.5 cu. in.)

BORE .........................................................................75.5 mm (2.97 in.)

STROKE ........................................................................82 mm (3.23 in.)

COMPRESSION RATIO ..................................................................9.4:1

INTAKE AIR ...............................................................Naturally Aspirated

NUMBER OF MAIN BEARINGS ...........................................................5

CONNECTING RODS .............................................. 4-Drop forged steel

CYLINDER HEAD .....................................................................S.O.H.C.

PISTONS ..................................................................... 4-Aluminum Alloy

CRANKSHAFT ...........................................................Drop Forged Steel

VALVE TRAIN

LIFTER TYPE ...............................................................Rocker Arm Type

INTAKE VALVE MATERIAL .....................High Temperature Alloy Forged

EXHAUST VALVE MATERIAL ................High Temperature Alloy Forged

VALVE SEATS ..................................................................... Replaceable

ENGINE GOVERNOR

❐ ELECTRONIC ...................................................................... Standard

FREQUENCY REGULATION, NO-LOAD TO FULL LOAD

STEADY STATE REGULATION ...............................................+0.25%

... Isochronous

■ Two pole, revolving field generator, directly connected to the engine
shaft through a heavy-duty, flexible disc for permanent alignment.

■ Generator meets the temperature rise standards for class "F"
insulation as defined by NEMA MG1-32.6.

■ All prototype models have passed a three-phase symmetrical short
circuit test to assure system protection and reliability.

■ All prototype models are tested for motor starting ability by
measuring the instantaneous voltage dip with a waveform data
acquisition system.

■ All models utilize an advanced wire harness design for reliable
interconnection within the circuitry.

■ Magnetic circuit, including skewed stator design, provides a minimal
level of waveform distortion and an electromagnetic interference
level which meets accepted requirements for standard AM radio, TV,
and marine radio telephone applications.

■ Voltage waveform deviation, total harmonic content of the AC
waveform, and T.I.F. (Telephone Influence Factor) have been
evaluated to acceptable standards in accordance with NEMA
MG1-32.

■ Alternator is self-ventilated and drip-proof constructed.

■ Fully life-tested protective systems, including "field circuit and

thermal overload protection" and optional main-line circuit breakers
capable of handling full output capacity.

■ System Torsional acceptability confirmed during Prototype Testing.

■ Generac H-100 Digital Control Panel

LUBRICATION SYSTEM

TYPE OF OIL PUMP .......................................................................Gear

OIL FILTER .................................................................Full flow, cartridge

CRANKCASE CAPACITY ............................................. 3.8 Liters (4 qts.)

COOLING SYSTEM

TYPE OF SYSTEM ...................................Pressurized, closed recovery

WATER PUMP ..................................................... Pre-lubed, self-sealing

TYPE OF FAN ............................................................................. Pusher

NUMBER OF FAN BLADES ..................................................................6

DIAMETER OF FAN ....................................................380 mm (15.0 in.)

COOLANT HEATER ............................................................120V, 500 W

FUEL SYSTEM

FUEL

❐ Natural Gas or L.P. Vapor ................................................. Standard

❐ L.P. Liquid Withdrawal ........................................................ Optional

CARBURETOR .......................................................................Down draft

SECONDARY FUEL REGULATOR ....... Nat. Gas or L.P. Vapor Systems

HOT WATER VAPORIZER..................... L.P. Liquid Withdrawal Systems

AUTOMATIC FUEL LOCKOFF SOLENOID.............................. Standard

OPERATING FUEL PRESSURE VAPOR SYSTEMS ........7" to 15" H2O

ELECTRICAL SYSTEM

BATTERY CHARGE ALTERNATOR ............................. 15 Amps at 12 V

STARTER MOTOR ...........................................................................12 V

RECOMMENDED BATTERY ............................(1) - 12 V, 530 CCA, 26F

GROUND POLARITY ................................................................Negative

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). Prime (Unlimited Running Time): Applicable for supplying electric power in lieu of commercially purchased power. Prime power is the maximum power available at
variable load. A 10% overload capacity is available for 1 hour in 12 hours. (All ratings in accordance with BS5514, ISO3046, ISO8528 and DIN6271).