Robin America RGV7500 User manual

SERVICE
MANUAL
Model
RGV7500
PlJB-GS1436
Rev. 05/00

Section Title Page
l.'SPECIFICATIONS ....................................................................................................... 1
2 . PERFOMANCE CURVES ........................................................................................... 2
3 . FEATURES .................................................................................................................. 3
3-1A.V.R. ALTERNATOR ............................................................................................. 3
3-2 OILSENSOR
........................................................................................................ 3
3-3
QUIET OPERATION ............................................................................................. 3
3-4 NO RADIO NOISE ................................................................................................ 3
3-5 LARGE FUELTANK
.............................................................................................. 3
3-6 RUGGEDTUBULAR FRAME ............................................................................... 3
3-7 COMPACTAND LIGHT WEIGHT ......................................................................... 3
3-8 MINIMAL MAINTENANCE .................................................................................... 3
3-9 LONG-LIFE DURABILITY
..................................................................................... 4
4 . GENERAL DESCRIPTION .......................................................................................... 5
4-1 EXTERNALVIEW ................................................................................................. 5
4-2 CONTROLPANEL ................................................................................................ 6
4-3 LOCATION
of SERIAL NUMBER and SPECIFICATION NUMBER ...................... 6
5. CONSTRUCTIONAND FUNCTION ........................................................................... 7
5-1CONSTRUCTION .................................................................................................. 7
5-2 FUNCTION ............................................................................................................ 7
5-3 GENERATOR OPERATION ................................................................................ 13
5-4 OILSENSOR ...................................................................................................... 16
6. SAFETY PRECAUTIONS ......................................................................................... 19
7 . RANGE OF APPLICATIONS .................................................................................... 20
8 . MEASURING PROCEDURES .................................................................................. 23
8-1 MEASURING INSTRUMENTS ........................................................................... 23
8-2AC OUTPUT MEASURING
................................................................................. 26
8-3 DC OUTPUT MEASURING ................................................................................. 26
8-4 MEASURING INSULATION RESISTANCE
........................................................ 27
9 . CHECKMG FUNCTIONAL MEMBERS .................................................................... 29
9-1 VOLfMtrER ....................................................................................................... 29
9-2 AC RECEPTACLES ............................................................................................ 29
9-3 No-FUSE BREAKER
........................................................................................... 29

Sectior! Title . Page
9-4 STATOR .............................................................................................................. 30
9-5 ROTORASSEMBLY ........................................................................................... 30
9-6 BRUSH
................................................................................................................ 31
9-7A.V.R. (AUTOMATICVOLTAGE REGULATOR)
.................................................. 31
9-8 IDLE CONTROL UNIT ........................................................................................ 33
9-9 DIODE RECTIFIER ............................................................................................. 34
9-1 0 OIL SENSOR .................................................................................................... 35
9-11 EXCITINGCOIL
................................................................................................ 35
1O.DISASSEMBLYAND ASSEMBLY ........................................................................... 36
10-1PREPARATION and PRECAUTIONS ................................................................ 36
10-2DISASSEMBLY PROCEDURES
....................................................................... 37
10-3 ASSEMBLY PROCEDURES ............................................................................ .. 45
10-4CHECKING, DISASSEMBLY
and REASSEMBLY of the FRONT PANEL ........ 50
11 . TROUBLESHOOTING ............................................................................................ 52
11-1 NO ACOUTPUT ................................................................................................ 52
11-2AC VOLTAGE IS TOO HIGHOR TOO LOW ..................................................... 53 \
11-3AC VOLTAGE IS NORMALAT NO.LOAD.
I
BUTTHE LOAD CANNOT BE APPLIED ..................................... 54
11 -4 NO DC OUTPUT ................................................................................................ 55
11-5 IDLE CONTROL(OPTI0NALEQUIPMENT) ..................................................... 56
12 . WIRING DIAGRAM ................................................................................................. 59
NOTE : As forthe servicing information on engine protion. pleasereferto the EH41 engine
sewice manual .

1. SPECIFICATIONS
Model RGV7500
j: U
Brush, Self Exciting, 2-Pole, Single Phase
60
Hz
~~ ~ ~ ~
Maximum Output
6000
W
Rated Output
7300
W
Rated
Current
Voltage 120V1240V 50N25A
Power Factor
1 .o I
DC Output 12V-8.3
A (1 00 W) I
VoltageRegulator I AVRType I
I Air-Cooled 4-Cycle, Overhead Valve Gasoline Engine I
Model EH41
D I
Displacement 404cm3(24.63cu.in.)
I
Rated Output 9.5
HP I 3600 rpm I
Fuel Automobile Gasoline
I
Fuel Tank Capacity 7.26 U.S. gal. (27.5 liters)
Rated Coutinuous Operation I Approx.7.0hours I
Oil Capacrty 0.32
US. gal. (1.2 liters)
Starting System
I RecoilStarterandOptionalElectricStarter I
Dimensions (L x W x H)
* Electric starter motor is availableasoption.
198.4 Ibs. (209.4 Ibs.)' 190kg (95 kg)*
Dry Weight
27.2
x 20.9 x 20.9 in. (690 x 530 x 530 mm)
- 1-

2. PERFOMANCE CURVES
RGV7500 / 60 Hz (6.0 kVN240V)
Load Rated
DC OUTPUT
DC Voltage ................. 12 V
DC Ampere ................ 8.3 A
DC output ................... 100 W
The voltage curve showninthe left indicates the characteristic of DC output when charging a battery.
The voltage
may be decreasedby 20% when the resistanceload is applied.
NOTE : It is possible to use both DC and AC outputs simultaneously up to the rated output in total.
f
\
- 2-

3. FEATURES
3-1 AVR ALTERNATOR
Output votage becomes more stable dueto AVR system.
3-2 OIL SENSOR
Oil sensor automatically shuts off the engine whenever theoil level fallsdown below the lowerlimitto
protect the engine from seizure.
3-3 QUIET OPERATION
Robin RGV series generator delivers a quiet operation with :
A quiet 4-stroke Robin Rro OHV engine.
Extra large muffler and large air cleaner provide remakable quiet operation.
3-4 NO RADIO NOISE
Noise suppressor spark plugisequipped standardto prevent radio frequency interference.
3-5 LARGE FUELTANK
The large fuel tank (27.5 L) allows more than 7 hours of continuous operation which is sufficient for a half
day or one day
work without refueling.
3-6 RUGGEDTUBULAR FRAME
Full cradle type rugged tubuler frame protects the generator all around.
3-7 COMPACT AND LIGHT WEIGHT
".
Newly developed brushless alternator enabled the RGV generators to be very compactinsize and light
in weight.
3-8 MINIMAL MAINTENANCE
A drip-proof alternator design.
No-fuse circuit breakers.
An electronic pointless ignition system.
- 3-

3-9 LONG-LIFE DURABILITY
The heavy-duty 4 stroke Robin OHV engine :
* Full rubber mount in a sturdy tubular frame.
* A forged steel crankshaft supported by two main ball bearings.
A pointless electronic ignition system.
* A cast-iron cylinder liner.
I
\
- 4-

4. GENERAL DESCRIPTION
4-1 EXTERNAL VIEW
FUEL GAUGE
CONTROL
PANEL
AIR CLEANER
RECOIL STARTER
IL GAUGE (OIL FILLER)
OILDRAINPLUGOIL
SENSOR
FUEL TANK
CHOKE LEVER
SPARK PLUG
CAP
OUTLET
- 5-

4-2 CONTROL PANEL
HOUR METERVOLTMETER PILOT LAMP
:\.ET3i STARTER TYPE) \ :;FEY AKCLE
\ \ I I
’
NO-FUSEBREAKERIDELCONTROL DC OUTPUT
SWITCH TERMINAL
I
ENGINESWITCH DC CIRCUIT BREAKER
(RECOIL STARTER TYPE)
4-3 LOCATION of SERIAL NUMBER and SPECIFICATION NUMBER
Serial number and specification number are stamped on the LABEL (MODEL NAME) stuck on the side
wall of rear cover.
I
NOTE : Always specify these numbers when inquiring about the generator or ordering spare parts in
order to get correct parts and accurate service.
LABEL, MODEL NAME
- 6-

5. CONSTRUCTION AND FUNCTION
5-1 CONSTRUCTION
STATOR. COMPLETE
MOUNTRUBBERBALLBEARING
TROUGH BOLTFRONTCOVER
Fig. 51
5-2 FUNCTION
5-2-1 STATOR
The stator consists of a laminated silicon steel
sheet core, a main coil and a condenser coil which
are woundinthe core slots.
The condenser
coil excites the rotor field coil which
generates
AC voltage inthe main coil.
3
Fig. 5-2
- 7-

5-2-2 ROTOR
The rotor consistsof a laminated silicon steel sheet
core
and a field coil which is wound over the core.
DC current in the field coil magnetizes the steel
sheet core. Two permanent magnets are provided
for the primary exciting action.
Slip
rings are provided on the rotor shaft to re-
ceive DC exciting current from A.V.R..
5-2-3 BRUSW BRUSH HOLDER
An exciting current is supplied from the A.V.R to
the rotor. The brushesare made
of carbon and
the brush-holderof plastic.
It is necessaryto keep the contact pressure be-
tween the brushes and slip rings withing specific
limits. Thus, care must be taken of brush length.
Fig. 5-3
5-2-4 A.V.R. (AUTOMATIC VOLTAGE REGULATOR)
The automatic voltage regulator employs an elec-
tronic circuit
to automatically regulate voltage.
Fig. 5-5
~
Fig. 5-4
- a-

5-2-5 IDLE CONTROL UNIT
The idle control unit releases throttle valve when
the applied load current exceeds
0'.04A.
The two output wires from the main coils must go
through the
ZCT inthe same direction.
NOTE :
It is normalthat the engine speed goesup for a
moment when you turn the key switchto "STOP"
while the Auto Idle Switch is in "ON" position.
I
Fig. 5-6
5-2-6 NO-FUSE BREAKER
The no-fuse breaker protects the generator from getting damage by overloading or short circuitinthe
appliance. Table
5-1 shows the capacity of no-fuse breaker by each spec. and their object of protection.
I
SPECIFICATION OBJECT
of PROTECTION
NO-FUSE BREAKER
60 HZ- 120 V/ 240V ' Total output amperage
25 A (2-Pole, 2-Element)
Table. 5-1
5-2-7 DC CIRCUIT BREAKER
The 10 ampere DC circuit breaker mounted on
the control panel protects whole
DC circuit from
getting damage by overload or short circuit.
Fig. 5-7
- 9-

Table. 5-2
Caution :
The duplex 120V receptacle is protected by a
GFCl (Ground Fault CircuitInterrupter).
GFCl shuts
off the output current from the
duplex
120V receptaclewhen a ground fault
occurs
in thegenerator or the appliance.
Pleasenote thatother receptacles are
not pro-
tected
by GFCI.
1
\ TWIST
1
Caution : To connect theappliancetolocking
receptacle, insert the
plug intothe re-
ceptacleand turn it clockwisetolock.
- 10-

5-2-9 GFCI RECEPTACLE
After starting the engine, checkthe GFCI for'proper functioning by the following test procedure.
Push blue TEST button, The red
RESET button will pop out exposing the word TRIP. Powerisnow off at
the outlets protected by the GFCI, indicating that the device is functioning properly.
If TRIP dose not appear when testing, do not use the generator. Call a qualified electrician.
To restore power, push RESET button.
WARNING :
If the RESET buttonpops out duringoperation, stop thegenerator immediatelyand call a
qualified electrician for checkinggenerator andtheappliances.
5-2-10 CONNECTING TO DOMESTIC CIRCUITS (HOUSE WIRING)
Fig. 5-9
WARNING :
This generator is a neutralgrounded type.
ff a generator is to be connected to residential or commercialpower lines, such asa stand-by
Faitwe in connectionmay result indeath, personalinjury, damageto generator, damagetoappli-
ances, damagetothe building's wiringorfire.
(a) When contnecting a Robin generatorto a house wiring, generator output power mustbetaken from
. power source duringpower outage, all connectionsmust be made by a licensedelectrician.
the 240V-4P receptacle.
- 11 -

Utility high line
House circuit
breaker
-
v
I I
I 120v
appliance
I
120v
appliance
-
240V
I
I
,A-
appliance
I
" -
I
I
"""""""""""""""""
= 4P- Receptacle
Fjg. 5- 70
(b) Installatransferswitch. i
I
A transfer switch must be installedto transfer the load from the commercial power sourceto the 1
generator. This switchisnecessary to prevent accidents caused by the recovery from power outage. '
Use a transfer switch of the correct capacity. Install transfer switch between the meter and the fuse or
AC breaker box.
Caution
: If the neutral wireof house wiring is grounded, be sure to ground the ground terminal of the
generator. Otherwise an electric shock may occur tothe operator.
(c) Operating the generator.
Set the full power switch to
120W 240V side.
Turn the house AC breaker
off before starting the generator.
Start the generator and warm
it up.
Turn the houseAC breaker on.
Caution
: Do not start the generator with electrical appliance (s) connected and with their switches on.
Otherwise the appliance
(s) may be damaged by the surge voltageat starting.
i
- 12 -

53 DESCRIPTION Of GENERATOR OPERATION
5-3-1 PRIMARY EXCITING ACTION
When the generator is started, the permanent
magnet on the engine rotates to generator a volt-
age inthe exciting coil. This voltage is regulated
by
a diode inthe A.V.R. to feed a current to the
generator field coil. (FC). (See Fig.
5-11)
The rotoristurned an electromagnet by that cur-
rent and rotates
so that voltage are generated in
the stator coils (main coil and sub coil). The volt-
age generated in the sub coilsis operated
by the
A.V.R. to feed a current to increase the field coil
current. (See Fig.
5-12)
As a result, the rotor magnetism increases.
This operationis repeatedto generate the rated
voltage at
60 Hz inthe main coil and DC coil.
5-3-2 VOLTAGE REGULATING MECHANISM
Connect a loadtotheAC output terminal and in-
crease current. Output voltage varies as shown
in Fig.
5-13 depending on whether an automatic
voltage regulatorisused or not.
The operation
of the A.V.R. is explained below.
When an AC output is taken, the engineisloaded
and itsrpm falls, Also the AC voltage fails due to
the voltage drop caused by the internal resistance
of the coils. The
A.V.R. detects this voltage drop
and its built-inSCR automatically increase the
current flowsto the field coil.As a result, the rotor
magnetism increase, the voltage fallenbythe load
current is raised: and the output voltageis kept
constant. If the AC output
is reduced, the SCR
operates in the opposite way to similarly keep the
output voltage constant.co,ndenser coil. When
current a increases, the density of magnetic flux
across the rotor core rises.As a result, the cur-
rent flowing
in the field coil increases and the gen-
erator
output voltage is prevented from decreas-
ing.
FC
n
EC i
L""""""-J
ENGINE MAGNETO
Fig. 5- 11
Fig. 5-12
WITHOUT AVR
RATED VOLTAGE
v
I
4A
Fig. 5- 13
- 13-

5-3-3 FULL POWER SWITCH (Dual Voltage Type)
The full power switch is providedfor the dualvoltage type to take out thefull ratedpower from one
receptacle
in each voltage.
120/240v
r--- 1
MC1 240v
1
-
-
t.-
Fig. 5- 14
MC1
MC2
Fig. 5- 15
MC1
MC2
1
Fig. 5- 15
-
1 REC.~
r
Switch
RECEPTACLE RECEPTACLE Position
HIGHER VOLTAGE
LOWER VOLTAGE
MC1
1
RECB Rated output
Half of rated output 120/240 V
Table. 5-3
-
-
MC2
I
I
-
Fig. 5- 16
- 14-

Two maincoils are wound over stator core. Each maincoil outputs half the rated power at the lower
voltage (120V). These main coils are woundto be inthe same phase. Thefull power switch reconnects
these main coilsinparallelor
in series.
Fig. 5-14 shows acircuitdiagram. When thefullpower switchisset for single lower voltage indication
(120V), the switch positionisas indicated by the lower solid lineinthe diagram. Fig.
5-1 5 isa simplified
representation ofthis circuit, showing the
two maincoils connected in parallel.Inthis case, the higher
voltage
(240V) at Rec. 3 cannot be taken out.Rec. 2 forthe lower voltage can output up tothe rated
power (upto
30A if the rated currentisover 30A), and Rec. 1 can output upto a totalof 15A.
When thefull power switchisset for double voltage indication (120V/240V), the switch positionisas
indicated by theupper dottedline in Fig. 5-1
4. Fig. 5-1 6 isa simplified representationof this circuit,
showing the
two main coils connectedinseries. Inthiscase, power can be taken simultaneously from
the receptacles for the both voltages. Rec.
3 for the higher voltage can output uptothe rated power, but
Rec.
1 and Rec. 2 for the lower voltage can output only upto half the rated power each.
Table
5-4 isa summary of the above explanation. Select.the proper output voltage byfullpower switchin
' accordancewiththeappliancetobeused.
- 15-

5-4 OIL SENSOR
541 DESCRIPTION
The oil sensormainly functions to detect posi-
tion of the surfaceof engine oil in the crankcase
of engines
for general use and to stop the en-
gine automatically when the oil level goes down
below the lower limit specified. This prevents sei-
zure of engine from occurring due to insufficient
amount of oil
in the crankcase.
Since the sensor has been designed to.consume
a part
of power supplied to the igniter to ener-
gize
its electronics circuit, any other external
power
supply is not necessary so that it can be
mounted at the oil filler port.
OIL SENSOR
Fig. 5- 17
Introduction of newly developed sensing principle features super durability and no change with the
passage
of time as it does not use any moving part.
Merits due to introductionof electrical conductivity detection are as follows ;
@ It has resistance to mechanical shocks and property of no change with the passage of time as
@ At the sametime, it is capable of detecting the oil level stably as it is not influenced by engine
@ No error occurs due to foam and flow of the oil.
@I Influence against the ignition system or the electronics units can be neglected because an electric
sensing
element consists simply of electrodes having no moving parts.
vibrations.
current
supplied to the sensor can be decreased.
5-4-2 PRINCIPLE OF SENSING OIL LEVEL
There is a great difference between electric resistance of air and that of oil. Since the resistance of air is
far higher than thatof oil, more electric current passes through the oil than through the air, although
absolute valueof the current
is very small. The sensor detects this current difference and make use of it.
The sensor judges the oil quantity, by comparing a current flowingacross apair of electrodes (inner and
outer) with the reference, in such a way that if a current flows between the electrodes more than the
reference, sufficient oil
is in the crankcase,on the other hand, if a current flows less than the reference,
oil is not sufficient. Since an electric current is flown to detect oil quantity, this is called the “electrical
conductivity detection” typeof sensor.
The oil level to be detected is determined by the length of elec-
trodes
and their mounting positions with the engine.
5-4-3 HOW IT OPERATES
[Power
supply]
The sensor makes use of a part of primary power source for ignition of the engine (igniter) to drive the
sensor circuit. Power to the sensor can usually be derived from the “stop button” by branching wires out.
- 16-

[Judgement of oil level]
When sufficient oilisinthe crankcase, both of inner and outer electrodes are immersedinthe oil through
which current flows across the electrodes. The sensor judges thatoil inthe crankcase is sufficient. When
oil level goes down and the inner electrode is exposed to the air due to consumption of oil, no current flow
between the electrodes as airis considered to be electrically nonconductive. The sensorinthis case
judges thatoil isinsufficient.
[Decision of oil shortage]
.Oil level at the electrodes may go down momentarily probably due to the engine being slanted or affected
by vibration even
if a sufficientoilis in the crankcase. For that reason, the sensor has an electronic timer
circuit to preventitfrom interpreting as short
of oil when amount ofoil is sufficient. The sensor has been
designed
so that the engine is to be stopped only when oil-shortage is detected for 5 seconds uninter-
rupted. The timer employs an integration circuit and
it is tobe reset when the inner electrode is soakedin
the oil again before the sensor decidesitas oil-shortage. The oil level where the sensor decides asoil-
shortage, whenoil levelgoes down gradually,iscalled "threshold level".
[Automatic stop of engine]
When the sensor decides as oil-shortage,it makes the engine to stop running automatically for protec-
tion
of engine. Oncethe stopping circuit is activated,itkeeps functioning untilitconfirms that the engine
has made a complete stop, then the circuit stops functioning automatically.
5-4-4 BLOCK DIAGRAM OF THE CIRCUIT
Power circuit igniter
Innerpole
-
Detection
-
circuit
circuit
'
Deley circuit
Stopping
oil 1 +
-Pole Engine ground
Fig. 5-18
0 Power circuit .......... This rectifies a part of power to the igniter and regulatesit to supply thest&+
lized power
to necessary circuits.
- 17-