Master MGR2900, MGR4500I, MGR6000I Owner's Manual

PORTABLE GASOLINE

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GENERATORS

OWNER’S OPERATION AND INSTALLATION MANUAL

Generator Models: MGR2900, MGR4500I, and MGR6000I

IMPORTANT: Read and understand this manual before operating or servic­ing generator. Improper use of generator can cause serious injury. Keep this
manual for future reference.

PORTABLE GASOLINE GENERATORS

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SAFETY
INFORMATION

WARNINGS

IMPORTANT: Read this owner’s
manual and the engine owner’s
manual carefully. Become familiar
with this generator before trying
to operate or service it. Know
its uses, limitations, and any
hazards involved. Improper use
of generator can cause severe
injury or death from explosion,
fire, burns, electrical shock, or
carbon monoxide poisoning.

DANGER: Carbon monoxide

poisoning may lead to death!

Engine exhaust contains poisonous carbon
monoxide gas. Overexposure will cause loss
of consciousness and will lead to death. Use
only in well-vented areas. Make sure area
has plenty of free-moving, fresh, outside
air. Never run generator in an enclosed or
confined area. Never run generator inside
occupied building.

Carbon Monoxide Poisoning: Early
signs of carbon monoxide poisoning re­semble the flu, with headaches, dizziness,
and nausea. If you have these signs, get
fresh air at once! Some people are more
affected by carbon monoxide than others.
These include pregnant women, persons
with heart or lung disease or anemia,
those under the influence of alcohol, and
those at high altitudes. Make certain
you read and understand all warnings.
Keep this manual for reference. It is your
guide to safe and proper operation of this
generator.

Safety information appears throughout these
instructions. Pay close attention to them.
Below are definitions for the safety informa­tion listed throughout this manual.

DANGER: indicates a hazard which will
cause severe personal injury, death, or
substantial property damage if you ignore
warning

WARNING: indicates a hazard which can
cause severe personal injury, death, or
substantial property damage if you ignore
warning.

.

CAUTION: indicates a hazard which will or
can cause minor personal injury or property
damage if you ignore warning.

1. Gasoline presents a hazard of fire or
explosion. Gasoline is flammable. Its
vapor is explosive.

• Keep fuel out of children’s reach.

• Refuel generator in a well-vented

area. Do not fill fuel tank in the dark.
Do not refuel while engine is run­ning. Unhook all electrical loads and
shut off engine before refueling.

• Do not overfill fuel tank. Always al

low room for fuel to expand. If you
overfill tank, fuel can overflow onto
hot generator. This can cause fire or
explosion. After refueling, tightly
close fuel tank cap.

• Do not spill fuel. Fuel or fuel vapor

may ignite. If fuel spills, make sure
area is dry before starting engine.

• Never smoke in refueling area. Never

allow open flames or sparks in area.

• Store fuel in approved container.

Store fuel in a well-vented area free
of open flames or sparks.

2. Guard against fire hazard. Keep opera­tion area well-vented. Keep generator at
least three feet away from any object.
Do not place flammable objects near
generator.

• Do not use generator where flam-

mable vapors are present. Some
vapors are heavier than air. These
vapors settle in low-lying places.

• Do not use generator in enclosed

spaces. This includes motor home or
RV generator compartments.

3.

Guard against electric shock. Generator
produces high voltage. This high voltage
can cause severe electric shock. Only
responsible adults should use generator.

• Properly ground generator before

starting.

• Never let anyone operate or service

generator without proper instruc
tions.

• Avoid contact with live terminals or

bare wires.

• Do not use generator outdoors in rain

or snow.

• Do not use generator near standing

water or snow.

• Do not use if generator is wet or

damp.

• Do not use generator in highly con­ductive areas. These areas include
metal decking and steelwork.

• Only use grounded extension cords.

• Do not use any worn or damaged
electric cords. Electric shock or dam­age to generator may result.

• Do not wear damp clothing or wet
shoes when using generator.

4. Guard against burns. Hot engine parts
can cause severe injury. Use caution
and remain alert when using genera-

-

-

tor.

• Keep children and animals away from

generator while it is running or hot.

• Keep all covers and shields in place.

Keep them tightly secured.

• The muffler becomes very hot dur-

ing operation. The muffler remains
hot for a while after shutdown. Do
not touch muffler while it is hot.
Do not let muffler touch anything
flammable. Let engine cool before
transporting or storing.

5. Have standby installation to home
or building performed by a licensed
electrician. Do not let anyone else wire
into a utility circuit. Personal injury,
equipment damage, or damage to home
could occur.

6. Never connect generator to any existing
electrical circuits. The generator output
will back-feed into the utility power line.
This may electrocute a power company
line repair person. Also, if generator is
powering electrical circuits, the chance
of an electrical fire exists.

7. Battery gives off explosive gases. Keep
sparks, flames, and cigarettes away. Do
not remove or install battery cables
when engine is cranking or running.
Only service or use battery in a well­vented area.

8. Battery contains sulfuric acid. Battery
acid is poisonous if swallowed. Contact
with skin or eyes may cause severe
burns. Do not tilt generator with battery
installed. Tilting could cause battery
acid to spill. Wear protective clothing
and face shield when servicing. Keep
out of children’s reach.

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OWNER’S MANUAL

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FUEL

SAFETY
INFORMATION

Continued

9.

Only a qualified electrical service person
should service and repair generator.

• Generator produces high voltage.
Use extreme caution when working
on electrical parts.

• Always remove spark plug wire from
spark plug before servicing. This will
prevent accidental starting.

•

When working on generator, avoid hot
muffler, exhaust manifold, and engine
parts. Severe burns may occur.

• Do not work on generator when
tired.

• Use only factory approved replace­ment parts.

10. Store generator in a well-vented area.
Make sure fuel tank is empty. Never
store with fuel in tank. Vapors may
reach an open flame or spark. Fire or
explosion may result.

11. Never operate generator

• if engine speed changes greatly

• if engine misfires often

• if powered items overheat

• if electrical output drops

• if it is sparking

• if it produces smoke or flames

• if it vibrates at high levels

• if it has a damaged receptacle

12. Keep gene rator and nearby are as
clean.

• Keep generator free of oil, mud, and

other foreign matter.

• Remove anything that creates slip-

pery areas around generator.

• Remove oily rags and other items

that create fire hazards.

• Keep a fire extinguisher nearby.

Make sure it is rated ABC by the
NFPA. They are good for all uses.
Consult your local fire department.

• Keep fire extinguisher well main-

tained. Be familiar with its use.

13. Know how to stop engine quickly.
Know how to use all controls.

14. Prolonged exposure to loud noise can
cause hearing loss.

• When working around generator,

wear approved hearing protection.

• Remember neighbors when using

generator.

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PRODUCT
IDENTIFICATION

Gas Tank

Ground Bolt

120 Volt Receptacle (GFCI)

Hour Meter

Auto-Idle Switch

Choke
Lever

Fuel Valve
Lever

Starter Grip

Engine

Engine ON/
OFF Switch

Figure 1 - Portable Generator (Model MGR4500I Shown)

3

Gas Cap/Fuel Gauge

120 Volt
Receptacle
(Duplex)

120 Volt
Receptacle

120/240 Volt
Receptacle

Voltage
Selector Switch

Circuit Breaker

Control Panel

Roll Cage

Oil Dipstick

PORTABLE GASOLINE GENERATORS

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GENERAL
INFORMATION

Master portable generators are rugged and
compact. These generators use brushless
alternators for dependable, trouble-free
service. Robin’s gasoline engines provide
long life under heavy use. These engines are
governed to maintain engine speed of 3600
RPM under load. 3600 RPM engine speed
provides 120/240V, 60 Hz power.

Additional Features

• Circuit breaker protection

• Spark-arresting muffler

• Large fuel tank

• Oil alert system

• 15-Amp ground fault circuit interrupter

(GFCI) receptacle

UNPACKING

1. Remove generator from carton.

2. Remove any protective packaging ap­plied to generator for shipment.

3. Check for loose or missing parts. Check
for shipping damage. If any parts are
missing or damaged, please contact our
Technical Service Department at 1-800­858-8501 (English Only).

VENTILATION

DANGER: Use only in well­vented areas. Make sure area
has plenty of free-moving, fresh,
outside air. Never run generator
in an enclosed or confined area.
Never run generator inside oc­cupied building. Engine exhaust
con t ains poi s onous ca r bon
monoxide gas. Overexposure will
cause loss of consciousness and
will lead to death.

This generator needs cooling air to run prop­erly. Never block free-flowing, cooling air
to generator. Overheating will occur without
cooling air. This will damage the generator.
Keep generator at least three feet away from
any object.

DUST, DIRT, RAIN,
AND SNOW

WARNING: Do not use genera­tor outdoors in rain or snow. Do
not use generator near standing
water or snow. Do not use if gen­erator is wet or damp. Operating
generator in these conditions
increases the risk of electrocu­tion. Severe injury or death can
occur.

Do not use generator in extremely dusty or
dirty conditions. This will severely affect its
life. Keep generator clean. Do not allow dust,
dirt, rain, or snow to collect on it. Protect
generator from outdoor elements.

HIGH AND LOW
TEMPERATURE
OPERATION

Air temperature affects generator output.
Output drops 1% for each 10° temperature rise
above 60° F. Very low temperatures may make
the engine hard to start. See engine owner’s
manual for more information.

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SPECIFICATIONS

OWNER’S MANUAL

MODEL MGR2900 MGR4500I MGR6000I

Electrical

Rated Wattage 2500 4500 6000
Rated Amperage

120 V 20.8 37.5 50
240 V –– 18.8 25

Receptacle

120-V, 20-A Duplex –– Yes Yes
120-V, 15-A GFCI Yes Yes Yes
120-V Twist-Lock –– 30 Amp 30 Amp
120/240-V Twist-Lock –– 20 Amp 30 Amp
120-V Voltage Selector Switch –– Yes Yes

General

Robin Engine H.P. 6 9 11.5
Robin Model EX170-D52010 EX270-0638T EH360-0644T
Fuel Type Gasoline Gasoline Gasoline
Fuel Tank Capacity 3.9 qt. 8 gal. 8 gal.
Oil Alert System Yes Yes Yes
Start Method Recoil Recoil Recoil
Weight (pounds) 85.5 135 165

* Single-phase, 1.0 power factor

Note: Ratings apply to SAE standard
conditions. Reduce ratings 3 1/2% for
each 1000 feet above sea level and 1% for
each 10° Fahrenheit rise above 60°F.

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5

PORTABLE GASOLINE GENERATORS

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ENGINE SW



ON

OFF

120v

ONLY

VOLTAG

E

Selector

120v

+

240v

120v

ONLY

VOLTAG

E

Selector

120v

+

240v

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GENERATOR
FEATURES

OIL ALERT SYSTEM

The oil alert system protects the engine from
low oil damage. This system automatically
shuts down the engine and prevents engine
restarting if the oil level falls too low.

Note: When this happens, the engine switch
remains in the ON position. The oil alert
system is wired into the ON/OFF Switch.

If this system shuts down the engine, the
engine will not start until you add oil. Add
oil to engine (see Engine Oil, page 7).

Note: Operate generator on a level surface.
If not level, the oil may flow away from the
oil level sensing device. This will cause the
oil alert system to shut down engine.

See engine owner’s manual for more
information.

Figure 2 - Engine Switch Location

VOLTAGE SELECTOR
SWITCH

All models except MGR2900 have a voltage
selector switch on the control panel. The
switch has two positions: 120 VOLT ONLY,
and 120 + 240 VOLT.

120 VOLT ONLY: This position sends full
power to the 120V receptacles only. 240V
power is not available. Use this position
when powering 120V items only.

120 + 240 VOLT: This position sends full
power to the 120/240V receptacle. It also
powers the 120V receptacles at reduced
wattage capacity.

IMPORTANT: Do not move the voltage se­lector switch while powering electrical items.
Unplug all items before moving switch. Failure
to do so can damage switch. Model MGR2900
does not have this switch. This model provides
full power to all receptacles.

120 VOLT ONLY

Position

Figure 3 - Voltage Selector Switch

120 + 240 VOLT

Position

AUTO-IDLE SYSTEM

(Except Model MGR2900)

The Auto-Idle System allows the engine to idle
down or run at a slower speed when the gen­erator is not being used to supply power. The
Auto-idle system can be turned ON or OFF by
a rocker switch on the control panel. When the
switch is in the OFF position, the engine runs
at full speed all of the time. When the switch
is in the ON position, the engine slows down
to idle speed until an electrical load is applied.
When a load is applied to the generator (an
electrical item is plugged in and turned on) the
engine speeds up to the preset speed required
to produce the correct voltage.

IMPORTANT: A minimum current load
of 1 Amp is required to disengage the auto
idle solenoid and cause the engine to come
up to speed for correct voltage. Powering
items at reduced engine speed will damage
generator and powered items.

GROUND FAULT CIRCUIT
INTERRUPTER RECEPTACLE

All models have a 120-volt ground fault
circuit interrupter (GFCI) receptacle. The
GFCI receptacle is on the control panel or top
cover of alternator (MGR2900). The GFCI
protects you against hazardous electrical
shock caused when your body becomes a
path through which electricity travels to
reach ground. This could happen when
you touch an appliance or cord that is ‘live’
through faulty mechanism, damp or worn
insulation, etc.

When protected by the GFCI, you may still
feel a shock, but the GFCI should cut it off
quickly. A person in normal health should
not receive serious injury. Note: Infants and
very small children may still be affected.

Test Procedure

Check the GFCI receptacle every month.
This insures it is working right.

1. Push TEST button. RESET button should
pop out. This should trip GFCI, result
ing in no electrical power at receptacle.
Verify this by plugging test lamp with
good bulb into receptacle. If lamp does
not work, GFCI receptacle is good.

WARNING: If RESET button
does not pop out, do not use the
GFCI receptacle. Contact a quali
fied electrician for repairs.

2. If the GFCI receptacle tests okay,
restore power by pushing the RESET
button back in. The test lamp should
work at this time. IMPORTANT: You
must press the RESET button firmly
and fully. It should lock into place. If
the GFCI does not lock into place, do
not use receptacle. Contact a qualified
electrician for repairs.

-

-

Figure 4 - GFCI Receptacle

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OWNER’S MANUAL

20

20

GENERATOR
FEATURES

Continued

RECEPTACLE CIRCUIT
BREAKER

The circuit breakers protect the receptacles
and alternator. Overloading generator will
trip circuit breaker. A short circuit in item
being powered will also trip breaker. If this
occurs, unplug electrical load from recep
tacle. Let circuit breaker cool down. Push
circuit breaker button to reset.

Electric motors need higher starting current.
They require up to three-times their rated
wattage to start. The starting current needed
may be too high. This can cause nuisance
circuit breaker tripping. To help prevent this,
start electric motors first. Connect additional
items to generator after starting motors. If
this continues to happen, reduce the total
generator load.

Note: High ambient temperature will cause
nuisance tripping.

TrippedNormal

Figure 5 - Receptacle Circuit Breaker
Button

ENGINE OIL

We ship the generator without oil in the
engine crankcase. You must add oil before
starting engine. See engine owner’s manual
for specific oil type.

CHECKING OIL LEVEL AND
ADDING OIL

Follow steps below to check oil level. Make
sure engine is level and stopped.

-

1. Remove dipstick (see Figure 6). Wipe
dipstick clean.

2. Insert dipstick into oil filler neck. Do
not screw it in. Oil level should be at
top of filler neck. Oil should cover most
of dipstick.

3. If level is low, fill to top of oil filler neck
(see Figure 6). Only use oil recom
mended in engine owner’s manual.

Note: If oil level is too low, oil alert system
will shutdown engine and prevent engine
from restarting.

Oil Level
At Top Of
Filler Neck

Oil

Figure 6 - Checking Oil Level (Model
MGR4500I Shown)

Dipstick

FUEL

WARNING: Gasoline presents
a hazard of fire or explosion.
Gasoline is flammable. Its vapor
is explosive.

• Keep fuel out of children’s

reach.

•

Refuel generator in a well­vented area. Do not fill fuel tank
in the dark. Do not refuel while
engine is running. Unhook all
electrical loads and shut off
engine before refueling.

• Do not overfill fuel tank. Always

allow room for fuel to expand.
If you overfill tank, fuel can
overflow onto hot engine. This

-

can cause fire or explosion.
After refueling, tightly close
fuel tank cap.

• Do not spill fuel. Fuel or fuel

vapor may ignite. If fuel spills,
make sure area is dry before
starting engine.

• Never smoke in refueling area.

Never allow open flames or
sparks in area.

• Store fuel in approved container.

Store fuel in a well-vented area
free of open flames or sparks.

Use clean, fresh, unleaded gasoline. Use
gasoline with octane rating of 86 or higher.
Service station gasoline pumps should dis­play the octane rating. Using gasoline with
lower octane level could damage engine.
Avoid getting dirt, dust, or water in fuel
tank. Do not mix oil with gasoline.

See engine owner’s manual for more
information.

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PORTABLE GASOLINE GENERATORS

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EXTENSION
CORDS

Only use grounded extension cords. Be sure
to use extension cord with proper wire gauge
size. See chart below.

Recommended Minimum Wire
Gauges (AWG) for Extension
Cords

Ampere AWG for Length of

Load Cord in Feet

50' 100' 150'

2 18 18 18

3 18 18 18
4 16 16 16
5 16 16 16
6 16 16 14
8 16 14 12
10 16 14 12
12 14 14 12
14 14 12 10
16 12 12 10
20 10 10 8

GENERATOR
GROUNDING

WARNING: You must prop­erly earth-ground generator be­fore starting. This will help guard
against deadly electric shock. Only
use grounded plugs with genera­tor. Only use grounded extension
cords. Only use three-wire or
double-insulated power tools.

5. Drive grounding point into ground.

Note: Grounding point can be a stake,
grounding rod, or pipe. Grounding
point should be copper or brass.

6. Attach ground wire to grounding point.

You must supply the ground wire and ground­ing point. These do not come with generator.
Follow the National Electrical Code and all
state and local codes. Consult your power
company or a licensed electrician.

WARNING: For a grounding
point, do not use metal pipe be­ing used to carry combustible
materials or gases.

Flat Washer

SEMS Nut

Ground Bolt

Spade
Connector

Detail A

Ground
Wire

STANDBY
INSTALLATION
TO HOME OR
BUILDING

WARNING: Have standby in­stallation performed by a skilled,
licensed electrician. Do not let
anyone else wire into a utility
circuit. Personal injury, equip­ment damage, or damage to home
could occur.

IMPORTANT: This generator will not
power your entire home. Most home utility
electric service is more than 60 amps. This
will exceed generator output. Only power
needed items during a power outage. Make
sure total wattage of electrical load does not
exceed rated wattage of generator.

You may need to use this generator as a
standby power source. During a power out
age, the generator will power selected items
in a building. Have generator and additional
wiring installed by a skilled, licensed electri­cian. This is not a do-it-yourself job. Follow
all local codes.

WARNING: The electrician
must install a doub le-throw
transfer switch. This isolates ex
isting electrical circuits from the
utility power line. If not isolated,
generator output will back-feed
into utility power line. This may
electrocute a power company line
repair person.

-

-

Grounding generator helps prevent electric
shock from a ground fault condition. Follow
these steps to ground your generator:

1. Locate ground bolt on generator hous

-

ing (see Figure 7).

2. Loosen SEM nut on ground bolt. Note:

Do not remove SEM nut from bolt.

3. Attach a spade connector to the end of
a #10-8 stranded-copper ground wire.

4. Attach spade connector to ground bolt
between flat washer and SEM nut (see
Detail A in Figure 7).

Copper or Brass

Alternator

Grounding Point

Figure 7 - Grounding Generator (Model
MGR4500I Shown)

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114716