● INDEX ●

Machine - 3 Division, Ahmednagar.

1. General Information 1

AL - SERIES AC GENERATOR 2. Principle of Operation 2

3. Machine Identification 2
Dear Customer,
4. Safety Requirements 3
Crompton Greaves Limited in Technical
Collaboration with world’s leading Alternator 5. Installation 10
manufacturers, combining up - to - the - minute
technology in our design and manufacturing, 6. Starting Up : Preliminary checks 12

together with a high standard of quality control,

7. Electrical Data (At 200C) 13
we are pleased to introduce our latest generation
of AC GENERATORS : The “AL - SERIES”. 8. Maintenance 15

9. Designation Of The Spare Parts 24

We request you to read this manual and follow
carefully the information on installation and 10. Exploded View : Alternator G2S/G1S 132 30
adjustments so that you may enjoy many years
11. Exploded View : Brushless Alternator 31
of dependable, trouble free operation.

12. Automatic Voltage Regulator :

Yours, AVR UVR - 6 32

“CROMPTON GREAVES LIMITED” 13. Dimension Drawing 37-42

1.0 GENERAL INFORMATION : l Motor starting capability : The Alternator is capable to start
The AL SERIES Alternators are manufactured using the most accurate 1.0 H.P. Induction Motor for its each kVA rating with DOL.
methods of design, construction and test. Their characteristics, if properly Motor starting applicable for only for S1 duty.
used, ensure a continuous working and a very prolonged trouble free l Steady State Voltage Regulation to the order of
life. For the best use of AL SERIES Alternators, please follow these ± 5% with compound excitation unit
instructions carefully. ± 1% with electronic regulator
At rated speed when supplying non - distorting, three- phase,
1.1 SPECIFICATIONS :
balanced, linear loads.
AL SERIES Alternators are self excited, self regulated and supplied l Volage build - up based on residual magnetism.
with Electronic voltage regulator or Compound Excitation Transformer.
They comply with the following International/Indian Standards :
1.6 OUTPUT VOLTAGE AND FREQUENCY
l ISO : 9001 The standard alternators are designed for supply voltage of :
l BS : 5000 - 415 V at 50 Hz in three phase.
l IS : 4722 & 13364 - 240 V at 50 Hz in single phase.
l CSA : Canadian Standard Association (1995)
2.0 PRINCIPLE OF OPERATION :
1.2 MECHANICAL FEATURES :
When started, the residual magnetism induces a voltage in the exciter
l Aluminum Body with integral N.D.E. shield, (upto 200 frame). armature. This voltage is rectified by the rotating diodes and fed to
l Cast Iron D.E. shield. the main field. The induced voltage in the auxiliary winding is then
l Life Lubricated sealed Ball Bearings, (upto 6313 size). used to increase the excitation power via the compound excitation
(CE) unit / electronic regulator (AVR) to the exciter field, to ensure a
l Screen protected Self ventilated Machine.
rapid and smooth build up of output voltage in the main stator winding.
l Degree of Protection : IP21 (IP 23 Optional)
On load, over load or short circuit the 'L' winding of CE Unit which
is in series with the load supplies an additional excitation voltage
1.3 NORMAL OPERATING CONDITIONS :
(the booster effect), to maintain the terminal voltage constant (within
l Altitude : Less than 1000m (3300 ft) ± 5% of rated value).
l Ambient temperature : Less than 400 C In case of alternator fitted with eletronic regulator (AVR SR 7/3 &
l Power Factor : From 0.8 lagging up to UPF UVR-6), AVR provides additional excitation requirements and maintains
terminal voltage constant (within ± 1% of rated value) from no load
1.4 LIMITS FOR SAFE OPERATION : to rated load condition.

l Over speed : 20 % (1800 rpm for 50 Hz)

3.0 MACHINE IDENTIFICATION :
l Over load : 110 % of rated value for one Hr.
Always indicate the Alternator Frame type and M/C Ref. No. with kVA
rating while contacting Factory or our authorized after sales service
1.5 ELECTRICAL FEATURES :
centres.
l Class H Insulation as standard

1 2
4.0 SAFETY REQUIREMENTS : l For handling the unpacked
l Before any cleaning, lubrication alternators, always use the
or maintenance operation, special eyebolts only, use ropes
ensure that the gen - set is having a suitable carrying
stationary and disconnected from capacity and do not lift the
the power supply. alternator too much from the
floor (max. 30 cm.)
While stopping the gen-set,
ensure the compliance with the The operators in charge of the
procedure for stopping the prime installations, operation and
mover. maintenance of the gen - sets
must be skilled technicians who
The alternator, in fact has no know the characteristics of the
emergency stop, but is controlled gen-sets.
by the device arranged by the
The operator must always wear
installer to stop the prime mover.
work gloves and safety shoes. In
l Before installing the alternator, case the alternator or whole DG-
arrangements must be made to SET must be lifted from the
earth the machine in compliance floor, the operators must wear a
with any relevant eletrical safety helmet.
regulations. This is the reason l Make sure that the gen-set
why installer must make sure foundations and base frame are
that the grounding system is in suitable to bear the combined
good conditions and in weight of the alternator and
compliance with the regulations prime mover.
of the country where the The alternator should be
generators will be installed. securely connected and perfectly
CAUTION : aligned with the prime mover,
THE FINAL INSTALLER IS otherwise dangerous vibrations
RESPONSIBLE FOR THE may occur resulting in alternator
INSTALLATION OF ALL THE bearing failure.
PROTECTIONS (SECTIONING l The machine has been designed
DEVICES, PROTECTION AGAINST to ensure the rated output when
DIRECT AND INDIRECT it is installed in a room having a
CONTACTS, OVERCURRENT AND max. temperature of 400 C and
OVER VOLTAGE PROTECTIONS, at an altitude not exceeding
EMERGENCY STOP ETC.) 1000 meters; in case of
NECESSARY FOR THE MACHINE deviations please make
TO COMPLY WITH THE EXISTING reference to our technical
INTERNATIONAL SAFTY REGULA- leaflets.
TIONS. l No person must wear fluttering
3 4
cloths (such as scarves etc.) near the machine and any such garment THE STARTING, RUNNING AND STOPPING OPERATIONS MUST BE
must be fastened with elastic bands at its ends. CARRIED OUT BY SKILLED PERSONNEL WHO HAVE READ AND
Alternator must never and for no reason run with following guards UNDERSTOOD THE SAFETY INSTRUCTIONS AT THE BEGINING OF
removed : THIS MANUAL.

l Terminal box cover PLEASE NOTE :

l Rear cover When the system is set to work for the first time, which has to be done
l Fan ventilation guard at reduced speed, the operator shall check that no anomalous noises
l Alternators produce heat proportional to the output. Therefore do is detected.
not touch it if you do not wear antiscorch gloves, and after If an anomalous noise is detected, stop the set immediately and improve
switching it off, do not touch it until it has cooled down. the mechanical coupling.

l Even if all machine components are protected, keep away from 4.4 CLEANING :
the gen-set. Do not lean or sit on the alternator for whatever Prior to approaching or touching the alternator, ensure that it is not
reason. live and it is at room temperature; at this stage it is possible to clean
it on the out side using compressed air.
4.1 DANGER OF SHORT CIRCUIT
NEVER USE LIQUIDS OR WATER FOR INSIDE CLEANING.
The degree of protection of the alternator is IP21. Short circuit may occur
if liquids (e.g. water etc.) are split onto areas containing electrical parts. DO NOT CLEAN INSIDE ELECTRIC COMPONENTS WITH THE
COMPRESSED AIR because this may cause short-circuits or other
4.2 TRANSPORT AND STORAGE anomalies.
Alternators will be packed for shipment in a manner suitable to their N.B.: The alternator frame is provided with many fixing holes so that
mode of transportation and final destination. vibration - damping may be applied in the proper position to ensure the
Prior to handling goods, please ensure that lifting equipment is of best trim of the gen-set.
sufficient capacity. Under lifting conditions machinery should be elevated
to a minimal distance from the ground. 4.5 MECHANICAL COUPLING :

Both packed and unpacked alternators shall be stored in a cool and dry CAUTION :
room, and shall never be exposed to the inclemency of the weather. ALTERNATOR FOOT FIXING ON THE DE SIDE IS ON END-SHIELD
Once the generator is coupled with an engine, mounted on a base FOOT. HENCE CARE MUST BE TAKEN WHILE CLOSING THE VENT
frame, or is installed on a complete gen-set, it can not be lifted by its COVER AFTER TIGHTENING THE BOLT THAT NO MATERIAL
lifting lugs. The relevant instruction for lifting the complete gen-set should SHOULD BE LEFT OUT INSIDE, WHICH MAY CAUSE DAMAGE OF
be followed. FAN UNDER OPERATION.

Any packing material should be disposed of via correct waste disposal

4.5.1 ASSEMBLY OF A.C. GENERATOR TO PRIME MOVER :
methods. Do not discard waste materials into the environment.
FOUNDATION :
4.3 STARTING AND STOPPING OPERATIONS : The machine should be mounted on a foundation, which may be of
All the instrumentation for starting, running and stopping the system shall steel structure or concrete platform. The foundation must be well
be provided by the installer. designed for adequate rigidity and long life, taking into consideration
5 6
the dynamic loading under abnormal running of the machine, vibration • Measure the diameter of the flexi disc and the engine flywheel drive
resulting from running machinery and other relevant factors. Care must disc recess dimensions C' and C as shown in the fig. 4.5. If there
be taken to ensure that the surface to which the machine is bolted is any variation contact the manufacturer.
down is aligned and levelled in all directions prior to mounting the • Check the rotor position by veryfing the dimension 'WA' & it should
machine. be equal to 'WB'.
• Measure the Pitch Circle Diameter of the fixing holes both on the
4.5.2 SINGLE BEARING GENERATORS : flexidisc and the engine flywheel drive disc recess (Dimension D
The rotor of the single bearing generator is locked by means of a and D' in fig. 4.5) If there is any variation, contact the manufacturer.
locking arrangement on the drive end side to prevent damage during Do not attempt to redrill the holes.
transportation. It is essential to remove this lock before coupling it • Check the engine flywheel runout and also the runout of the
to the (prime mover) engine. The sequence is as follows. flywheel housing.
• Position and align the prime mover. • After the above checks have been made the machine is ready for
coupling.
• On the engine measure the distance between the engine bell
• The generator is supported using a hoist and the machine is moved
housing mounting surface to the drive discs recess in the engine
horizontally towards the engine flywheel. Ensure that the flexi discs
flywheel. Dimension 'WB' is shown in the figure 4.5.
are properly seated within the drive disc recess in the engine
• Measure the distance from the alternator end shield spigot (adaptor flywheel.
spigot) face to the outside surface of the flexible disc assembly • Fix the bolts between the flexi disc and the flywheel. The bolts
(Dimension 'WA' as shown in the figure 4.5. Ensure that the are to be tightened alternately and evenly. Also, the bolts fixing
generator is parallel to its frame while measuring the distance 'WA'. the adaptor to the engine housing are to be tightened.
• Now run the machine to its full speed and check for the vibration.

1) NUMBER OF COUPLING DISCS & TIGHTENING TORQUE FOR

1-BRG.ALTERNATOR :
When fitting coupling discs ensure that the number and
thickness of discs, and tightening torque of hub bolts is in
accordance with the table below.
A) For coupling disc SAE 10”/11.5”/14”

FRAME NO.OF SINGLE DISC TOTAL TIGHTENING

DISCS THK(mm) THK (mm) TORQUE
132/160 2 1.2 2.4 24.9kg-m
(244 N-m)
200/250 3 1.2 3.6 24.9kg-m
(244 N-m)
280 4 1.2 4.8 24.9kg-m
(244 N-m)
315/355 4 1.2 4.8 48 kg-m
(480 N-m)
7 8
B) For coupling disc SAE 6.5”/7.5” :- 5.0 INSTALLATION :

FRAME NO.OF SINGLE DISC TOTAL TIGHTENING Unpack the alternator, check for any damage to the packing case. If
DISCS THK (mm) THK (mm) TORQUE any damage is visible, it is possible the alternator itself has been
damaged.
132/160 2 2.0 4.0 6 kg-m (59 N-m)
Such damage should be reported to the transporter and insurance
2) “WA” DIMENSION : agents.
After fitting coupling discs ensure that the “WA” is in accordance 5.1.1 LOCATION - COOLING :
with the table below for various coupling disc SAE ( Measure “WA”
The air in which the alternator is installed shall be such that the
near to the Rt. Locking plate)
ambient temperature never exceeds 400C (at nominal ratings). For
WA END-SHIELD
higher ambient a derating factor should be applied.
C.DISC "WA" DIMN. Fresh air, free from humidity and dust, must circulate easily through
SAE (MM)- ±0.5
SPACER
the screen at the non-drive end of the alternator. The recycling of
6.5"/7.5" 30.2 (WHEN
FITTED) heated air, from the D.E. or circulating from prime mover, should be
10" 53.8 M16x45(8.8 CL) avoided as far as possible.
COUPLING HUB
11.5" 39.6 Ensure adequate ventilation for a good air flow at all times.
14" 25.4
SHAFT
5.1.2 OPERATING IN PARTICULAR ENVIRONMENTAL
CONDITIONS :
l If the alternator is going to be operated at altitude higher than 1000
Mt. above sea level it is necessary a derating of 4% each 500
4.5.3 DOUBLE BEARING GENERATORS :
Mt. of increase.
• The prime mover is placed on the bed plate and aligned. l If the ambient temperature exceeds 400C it is necessary a derating
• The drive end of the shaft is cleaned well and half coupling is of 4% each of 50C of increase.
fitted to it. The key provided on the shaft is only to be used for
l If the alternator is going to be used in a sound proof set, make
fixing half coupling. The half coupling should be heated and fitted
sure that only fresh air enters it; place the alternator air inlet near
on the shaft. Hammer blow fixing of the half coupling is to be
and infront of air opening.
avoided. The heated half coupling should be cooled by blowing air
Remember that the air required for alternator is :
over it. Attempt should not be made to cool the coupling by
sprinkling water over it. The tapped hole provided at the shaft end 50 Hz 60 Hz
can be used to press in the half coupling.
132 Frame, 4 pole 5 m 3/min 6 m3/min
• The generator is positioned on the base plate and the centre height,
transverse and the axial positions are adjusted. 160 Frame, 4 pole 9 10.8
• The generator coupling is then engaged with that of the prime 200 Frame, 4 pole 20.5 24.6
mover. 250 Frame, 4 pole 26.5 31.8
• Now proceed to check the alignment in accordance with the 280 Frame, 4 pole 34.0 40.8
coupling manufacturers recommendations. 315 Frame. 4 pole 50 60
• When the machines are perfectly aligned, the holding down bolts
355 Frame, 4 pole 80 96
are tightened.
9 10
5.2 ELECTRICAL CHECKS : 6.0 STARTING UP :
Before putting the machine into service, an Insulation Resistance check 6.1 PRELIMINARY CHECKS :
between phase and earth and between phases is recommended. For
this test every single parts to be checked has to be isolated from 6.1.1 MECHANICAL CHECKS :
the others. This test should be done with a “megger” using 500 V
Before starting up, check :
DC. The insulation resistance when machine is cold should normally
be >10 mega ohms. l that all foot and flange bolts are tightened

CAUTION : Machine whether new or used should not be operated l that the cooling air circulates freely around and through the
if insulation resistance is less than 1 mega ohm for stator and machine
other windings. l that all louvers, guards, etc. are correctly fitted
If megger value is low, the machine must be dried until the minimum
value is obtained. 6.1.2 ELECTRICAL CHECKS :
Make sure :
To get the minimum value, there are several methods :
a) Bake the machine for 24 Hr. in an oven at 1000C. l A suitable eletrical protection device is fitted in the output
circuit for safty reasons (in line with the codes of practice
b) Dry out the machine with a stream of hot air.
in force within the country where the alternator is installed)
c) Disconnect the CE Unit (For G2S series) and AVR (in case of G2R
series). l Ensure before star t up that ter minal nuts are properly
tightened.
l shor t circuit the three output (power) ter minals through
connections capable of carrying rated current. l The control panel protection equipment is correctly set.
l with an appropriate ammeter, monitor the current flowing in l There is no short circuit due to wrong connections either /
the short circuited connections. or in between the terminals of the alternator and the power
l connect a 48 V storage battery to the field winding terminals switch or breaker (this part of the circuit is not protected
of the exciter (respecting polarities), fitted in series a rheostat by the breaker).
of about 20 ohms (250 watts)
l When the alternator is operating at nominal voltage, at no
l open completely all the apparatus of the alternator, terminal load, DC voltage at field Wdg (Vf) should approximately
box panels, protection screens etc. match with the values as mentioned in the Table (7.0)
l star t up the gen - set to its rated speed and adjust its
excitation through the rheostat in order to obtain the rated
current in the short circuited connections & run under this
condition for 1/2 hr. to get 1MW Insulation Resistance.

5.3 DIRECTION OF ROTATION :

The alternator can be driven in either direction of rotation but standard
phase sequence is U-V-W, when rotation is clock wise looking in the
drive end.
For anticlock wise rotation interchange the two phases V and W to
get U-V-W phase sequence.
11 12
 7.0 ELECTRICAL DATA (AT 200C) :
TYPE WINDING RESISTANCE (in W) (MIN/MAX) EXCITATION DATA
ALTERNATOR AUXILIARY COMPOUND X-mer (CE - unit) NO LOAD FULL LOAD
STATOR (PH) ROTOR WINDING (L-L) L WDG (m-ohms) C WDG (ohms) Vf (DC) If(DC) Vf (DC) If (DC)
G2S 132 MR 2.308/2.400 11.50/11.96 2.45/2.57 177.1/186.0 1.20/1.26 25 2.2 80 5.8
G2S 132 MA 1.496/1.556 14.00/14.56 2.17/2.28 97.0/101.9 1.12/1.18 30 2.2 80 5.8
G2S 132 MC 0.968/1.007 16.50/17.16 1.92/2.02 64.5/67.7 1.04/1.09 35 2.2 95 5.8
G2S 132 MD 0.733/0.762 19.00/19.76 1.83/1.92 48.5/50.9 1.12/1.18 45 2.2 110 5.8
G2S 132 LC 0.600/0.624 22.40/23.30 1.69/1.77 27.5/28.9 1.04/1.10 50 2.2 130 5.5
G2S 132 MA-1PH 0.825/0.858 14.00/14.56 1.75/1.84 61.8/64.9 1.19/1.25 30 2.0 80 5.5
G2S 132 MC-1PH 0.597/0.621 16.50/17.16 1.70/1.79 38.8/40.7 1.19/1.25 35 2.0 95 5.5
13

G2S 132 MD-1PH 0.409/0.425 19.00/19.76 1.45/1.52 25.0/26.3 1.19/1.25 40 2.2 110 5.5
G2S 132 LC-1PH 0.356/0.370 22.40/23.30 1.64/1.72 17.0/17.9 1.19/1.25 50 2.0 130 5.5
G2S 160 SC 0.313/0.326 27.30/28.39 0.95/1.00 15.0/15.8 0.89/0.94 55 2.0 150 5.3
G2S 160 MA 0.232/0.241 32.10/33.38 0.83/0.87 9.6/10.1 0.89/0.94 65 2.0 175 5.3
G2S 160 MB 0.155/0.161 38.30/39.83 0.77/0.81 6.7/7.0 0.89/0.94 70 2.0 210 5.3
G2S 160 SC-1PH 0.211/0.219 27.30/28.39 0.92/0.97 8.5/8.9 0.85/0.89 55 1.9 140 5.0
G2S 160 MA-1PH 0.129/0.134 32.10/33.38 0.82/0.86 5.8/6.1 0.90/0.95 65 1.9 160 5.0
G2S 200 SA 0.138/0.144 29.80/30.99 0.82/0.86 7.5/7.5 1.03/1.08 65 2.0 175 5.6
G2S 200 SB 0.100/0.104 33.10/34.42 0.67/0.70 6.8/7.1 1.03/1.08 70 2.0 200 5.6
G2S 200 SD 0.070/0.073 37.35/38.84 0.77/0.81 5.2/5.5 1.03/1.08 75 2.0 240 5.6
G2S 200 MD 0.036/0.037 39.30/40.87 0.62/0.65 3.0/3.2 0.77/0.81 90 2.0 250 5.6

TYPE WINDING RESISTANCE (in W) at 200C (MIN/MAX) EXCITATION DATA

ALTERNATOR AUXILIARY EXCITER NO LOAD FULL LOAD
STATOR (PH) ROTOR WINDING (L-L) STAT. (ohms) ROT.(ohms) Vf (DC) If(DC) Vf (DC) If (DC)
G2R 160 SA 0.745/0.775 4.54/4.72 2.89/3.03 13.64/14.19 1.060/1.102 10 0.8 35 2.2
G2R 160 SB 0.459/0.477 5.30/5.51 2.25/2.36 13.64/14.19 1.060/1.102 10 0.8 35 2.2
G2R 160 SC 0.335/0.348 5.95/6.19 1.98/2.08 13.64/14.19 1.060/1.102 10 0.8 35 2.2
G2R 160 MA 0.236/0.245 6.66/6.93 1.71/1.80 13.64/14.19 1.060/1.102 10 0.8 35 2.2
G2R 160 MR 0.21/0.218 7.25/7.54 1.75/1.84 13.64/14.19 1.06/1.10 10 0.8 35 2.2
G2R 160 MB 0.183/0.190 8.19/8.52 1.56/1.64 13.64/14.19 1.060/1.102 10 0.8 35 2.2
G2R 160 SB-1PH 0.366/0.381 5.30/5.51 N.A. 13.64/14.19 1.060/1.102 06 0.5 30 1.7
G2R 160 SC-1PH 0.267/0.278 5.95/6.19 N.A. 13.64/14.19 1.060/1.102 06 0.5 30 1.7
G2R 200 SA 0.148/0.154 2.52/2.62 1.77/1.86 15.58/16.20 0.266/0.277 10 0.6 35 2.0
G2R 200 SB 0.109/0.113 2.70/2.81 1.56/1.64 15.58/16.20 0.266/0.277 10 0.6 35 2.0
14

G2R 200 SD 0.080/0.083 3.14/3.27 1.38/1.45 15.58/16.20 0.266/0.277 10 0.6 35 2.0

G2R 200 MD 0.044/0.046 4.03/4.19 1.19/1.25 15.58/16.20 0.266/0.277 10 0.6 35 2.0
G2R 200 MDX 0.051/0.053 1.0/1.04 1.25/1.31 15.58/16.20 0.118/0.123 10 0.6 40 2.2
G2R 250 MC 0.038/0.040 1.46/1.54 1.30/1.37 17.5/18.5 0.170/0.180 8 0.46 55 2.5
G2R 250 MD 0.036/0.037 1.64/1.71 1.40/1.48 17.5/18.5 0.170/0.180 8 0.46 55 2.5
G2R 280 MA 0.027/0.029 1.70/1.78 1.23/1.29 17.5/18.5 0.170/0.180 10 0.50 60 2.8
G2R 280 MB 0.023/0.0245 1.82/1.92 1.06/1.12 17.5/18.5 0.170/0.180 10 0.50 60 2.8
G2R 280 MD 0.0175/0.0190 1.95/2.05 1.07/1.13 17.5/18.5 0.170/0.180 10 0.50 60 2.8
G2R 280 LB 0.017/0.0180 2.23/2.35 1.22/1.28 17.5/18.5 0.170/0.180 10 0.50 60 2.8
G2R 280 LD 0.015/0.016 2.44/2.56 1.25/1.31 17.5/18.5 0.170/0.180 10 0.50 60 2.8
G2R 315 SB 0.0077/0.0083 2.3/2.5 0.47/0.51 21.1/22.9 0.38/0.42 16 0.7 75 2.5
G2R 315 MB 0.00712/0.0078 2.7/2.9 0.47/0.51 21.1/22.9 0.38/0.42 16 0.7 75 2.5
G2R 355 SB 0.0053/0.0057 2.7/3.1 0.21/0.23 24.5/26.5 0.20/0.22 18 0.7 90 3.7
G2R 355 SC 0.0048/0.0052 3.2/3.46 0.21/0.23 24.5/26.5 0.20/0.22 18 0.7 90 3.7
8.0 MAINTENANCE : potentiometer ‘VOLT’ of the AVR.
8.1 COOLING CIRCUIT :
It is recommended to check that the cooling air circulation is not restricted. 8.4 REMOTE REGULATION OF THE VOLTAGE :
(for Brushless)
8.2 BEARINGS :
The bearings of the alternators are self lubricated and do not require Remote voltage adjustment 0f ± 5% is possible with 100 KW
maintenance for a period of working of approximately 15,000 Hours. potentiometer. For details refer AVR connection diagrams.

8.3 VOLTAGE SETTING AND REVOLVING SPEED : WARNING : FOR ALTERNATOR GOOD WORKING IT IS ADVISABLE
NOT TO DEVIATE FROM THE NOMINAL VOLTAGE BY MORE
The output voltage of the alternator should be checked at the nominal
THAN 5%
revolving speed 1500 R.P.M.
8.3.1 SLIPRING ALTERNATORS 8.5 VOLTAGE BUILD UP - BY FIELD FLASHING AT NO LOAD :
Usually the alternators are preset at the factory to suply voltage
The alternator is self exciting from the residual magnetism of the
slightly higher ( from 3 to 5 % ) than the nominal one at the nominal
magnetic circuit of the exciter. When first tested (at the factory) this
revolving speed. In Frame G2S 132 / 160 / 200 if one want to regulate
magnetic circuit is magnetized. After a breakdown it may be necessary
the no load voltage of the alternator at determined revolving speed it
to remagnetise.
is necessary to operate on the air gap of the compound transformer
as follows, referring to fig. 8.3. Proceed as follows for field flashing :
1) Loosen the two screws N. Connect a 12 - 24 V battery to the terminals of the exciter field (main
N
2) Regulate the air - gap field winding for Slipring types) for two to three seconds.
considering that.
CAUTION : ENSURE THAT THE SET IS NOT RUNNING BEFORE
a) if one increases it, the
PROCEEDING FOR FIELD FLASHING & EXCITER FIELD
voltage will increase.
CONNECTIONS TO THE AVR ARE REMOVED IN G2R/G1R FRAME.
b) if one narrow it, the
N
voltage will decease. 8.6 INSTRUCTION FOR THE DISASSEMBLY
If the voltage variation required is OF THE ALTERNATORS
higher than 5% it is necessary to Air Gap
T The following section explains step by step procedure for the
replace the insulating paper (T) of
Fig. 8.3 disassembly of the alternators and the truobleshooting of the faults :
the air gap.
3) After setting the voltage tighten up the two screws N. BEFORE PERFORMING THIS OPERATION, KINDLY READ THE
SAFTY REQUIREMENTS AT THE BEGINNING OF THIS MANNUAL
In addition to air gap adjustment, voltage can also be adjusted by
CAREFULLY.
changing the taps on capacitor. By changing taps from 1 towards 9
will decrease the voltage & vice-versa. (For details refer instructions 1) Remove the terminal box cover.
provided on capacitor). For Single Phase Slipring type Alternator, CE 2) a) IN Slipring Alternator :
Unit is provided with a tapping for convenience of Voltage setting.
Disconnect the two terminals of the field winding from
Connections to 'LHS' terminal of the 'C' wdg. will boost up the terminal
the rectifier bridge
voltage.
b) IN Brushless Alternator :
8.3.2 BRUSHLESS ALTERNATORS
In case of alternators equipped with eletronic voltage regulator, one Disconnect the connections between the winding and the AVR.
can regulate the no load voltage of the alternator by operating on the
15 16
3) Remove the end cover of Slipring Alternator : Before
4) Disconnect from the rotating rectifier the two wires going to the withdrawing the rotor from the
main field. stator it is necessary to
remove the brush holder
5) Remove the rotating rectifier after screwing out the fastening
assembly).
screws.
12) Remove the bearings, using
6) Take away the diode holding
suitable puller & use pressing
support by removing three M-6
technique with suitable mandrel
Allen screw. (See fig. 8.6.a)
for refitting the bearings on the
shaft. (See fig. 8.6.c) Fig. 8.6.c

8.6.1 MOULDED RECTIFIER BRIDGE

(Slipring Type Altermator) :
The moulded bridge rectifier used is of rating 25A, 800V
7) Unscrew the three M-8 screws Three phase alternators are equipped with three - phase bridges while
which fasten the exciter stator. the single phase alternators are supplied with single - phase bridges.
8) Remove the exciter stator. Fig. 8.6.a
9) Make use of three M-6 tapped 8.6.2 RECTIFIER BRIDGES CHECKOUT :
holes on exciter rotor for its To check each diode of the rectifier bridge one can use either an
removal with suitable puller. ohmmeter or a battery with a bulb, as follows :
(See fig. 8.6.b)
A diode is working :
l when, with an ohmmeter, one can verify that the resistance is
very low in one direction and very high in other direction.
l when a battery and a bulb, the bulb will light up with one of
the two possible connections, as illustrate in the diagram 8.6.2.

Lamp Off Lamp turned on

10) Unscrew the DE end shield Fig. 8.6.b

fixing screws and remove DE
end shields.
11) Remove the rotor from the stator paying attention not to damage
the windings by holding the rotor properly using a hoisting
Fig. 8.6.2
mechanism with soft rope of sufficient strength. Place the rotor
in the work area which has been previously prepared. (In case
17 18
8.7 HELPFUL HINTS IN TROUBLE SHOOTING
When an eletrical failure occures, check for trouble as explained
below :
1) In order to find out if the failure has happened in the alternator
itself or in the regulation system one has to test the alternator at
no load (at nominal speed) exciting the exciter stator directly, using
an external dc source.

When applying the voltage to the exciter stator one has to comply
with polarities : apply the negative polarity of the auxiliary source
to the negative terminal and positive terminal to the positive terminal
of the exciter fields.
Verify that :
A) When feeding the winding according to the excitation data at
no load (listed in the table) the voltage supplied by the
alternator is almost the rated one
B) After the localization of fault, repair properly.

8.8 Possible Faults :

While running, if the alternator is not functioning properly, first check :
That the connections as per specified diagram for the machine
That the connections are properly tightened
That the running speed of the prime mover is correct (frequency
meter)
That the protection equipment is properly set.

19
 l VOLTAGE FAULTS :

FAULT CAUSE REPAIR

No voltage build - up 1) Insufficient residual voltage 1) Excite the rotor using a battery
2) Improper connection 2) Correct the connection
3) Faulty moulded rectifier bridge 3) Replace the rectifier bridge
4) Low speed 4) Reset the speed to the nominal
5) Faulty Winding 5) Check the winding resistance
and rewind if required
6) Rotating rectifier failure 6) Replace the rotating rectifier
7) Faulty AVR 7) Replace the AVR
20

Low no - load voltage 1) Low speed 1) Reset the speed to the nominal
2) Air - gap of compound too small 2) Regulate the compound air gap
3) Faulty Rotating rectifier 3) Replace the rotating rectifier
4) Faulty Winding 4) Check the winding resistance
and rewind if required
5) Faulty moulded bridge rectifier 5) Replace the rectifier bridge

Low voltage on load 1) Low speed at full load 1) Set the rated speed of the
prime mover
2) Compound defective 2) Check and, if necessary change
the compound unit
Continued . . . .

VOLTAGE FAULTS :

FAULT CAUSE REPAIR

Low voltage on load 3) Faulty rotor winding 3) Check the rotor winding
resistance and if faulty, rewind it
4) Over load on alternator 4) Operate on specified load

High voltage on load 1) Capacitors on the load side 1) Disconnect the PF

improvement capacitors
2) Incorrect compuond assembly 2) Check the compound winding
resistance & if necessary replace it.
21

Too high 1) Excessive speed 1) Adjust the revolving speed

no - load voltage 2) Air - gap compound too high 2) Reduce the compound air gap

Voltage oscillations 1) Incorrect AVR setting 1) Set the AVR stability pot
2) Thyristor load more than 2) Reduce the Thyristor load
specified limits
3) Insufficient engine flywheel

Unbalance voltage 1) Unbalance load 1) Correct the load

2) Loose connections 2) Tighten the loose connections
3) Stator winding faulty 3) Check winding resistance &
rewind if required
 l Evident Physical Defects (overheating, noise, vibration....)

FAULT CAUSE REPAIR

Excessive overheating 1) Set misalignment 1) Align the set properly

of one or both bearings 2) Bearing loose in end shield 2) Replace the faulty End shield
(temp. of bearings over housing
800C) (with or without
noise)

Excessive overheating 1) Air flow (inlet - outlet) partially 1) Check air inlet - outlets of the
of alternator frame clogged or hot air is being alternator
circulated either from alternator
22

or prime mover
2) Alternator operating at high 2) Set the voltage to rated value
voltage at load
3) Alternator overloaded 3) Operate at specified load
4) Load PF less than 0.8 lag 4) Correct the load power factor

Excessive vibrations Defective mounting or play in the Replace the coupling & check the
coupling alignment Reset the speed to the
nominal

Excessive vibration and 1) Three phase alternator is 1) Check and correct the load
humming noise coming single phase loaded in excess
from the alternator of acceptable limits
Continued . . . .

Evident Physical Defects (overheating, noise, vibration....)

FAULT CAUSE REPAIR

Excessive vibration and 2) Start up with no-load : if humming 2) Rewind stator

humming noise coming persists - faulty alternator stator
from the alternator winding

Smokes, spark or flames Short circuit in the external circuit Stop the set immediately
coming from the (including wiring between alternator and
alternator control board)
Object fallen into the machine
23

Short circuit or flash in the stator

winding

Short circuit in external circuit Stop the gen-set immediately

Alternator damaged by a Faulty parallel connection (out of
significant impact which phase)
is followed by humming
Break or deterioration in the coupling
and vibration
Break or twist in shaft extension
Shifting or short circuit of main field
winding
Bursting or unlocking of the fan
Diode burnt, rectifier bridge damaged
 G1R 250/SAE3 - 6085243032
9.0 DESIGNATION OF THE SPARE PATRTS :
G1R 250/SAE1 - 6085243012
In case of replacements of spare parts use original spare parts only G1R 280/SAE1 - 6099243012
G1R 315/SAE1 - 6009243012
for the best performance of alternator. G1R 355/SAE1 - 6019243012
For the replacements of worn parts, carefully follow the maintenance 11 NDE END SHIELD
250 Frame - 60812432
instruction, these operations must be carried out by skilled and trained
280 Frame - 60992432
technicians or our authorized service personnel. 315 Frame - 60092432
355 Frame - 60192432
46 MOULDED SLIPRING
PA RT DESCRIPTION RECOMMENDED ORDERING
G2S/G1S 132 Frame 1 365241001
NO. SPARES QTY. CODE
G2S/G1S 160/200 Frame 1 361241004
3 FRAME WITH WND PAC K - Ref. to Divn. 47 FAN
4 ROTOR (Wound) - Ref to Divn. 132 Frame - 368022007
7 WOUND EXCITER STATOR 160 Frame - 369022004
160 Frame - 60492416 200 Frame - 60612423
200 Frame - 60692416 250 Frame - 67536223
200MDX/250/280 Frame - 60992416 280 Frame - 60992423
315 Frame - 60092416 315 Frame - 60092423
355 Frame - 60152416 355 Frame - 60192423
8 WOUND EXCITER ROTOR 51 END COVER/TERMINAL BOX
160 Frame - 60492425 132 Frame - 362022007
200 Frame - 60692425 160 Frame - 361031007
200MDX/250/280Frame - 60992425 200 Frame - 369031002
315 Frame - 60092425 T. Box ASBY G1R 250 - 361055002
355 Frame - 60152425 T.Box ASBY G1R 280 - 361055001
T.Box ASBY G1R 315 - 361055003
10b M/CD DE END SHIELD (G2R) T.Box ASBY G1R 355 - 361055004
132 Frame 60351430
160 Frame - 60492430 53 DE VENT COVER
200 Frame - 60692430 G2R 132 Frame 361034016
250 Frame - 60852430 G2R 160 Frame - 363034003
280 Frame - 60992430 G2R 200 Frame - 360034001
315 Frame - 60092430 G2R 250 Frame - 340034065
355 Frame - 60192430 G2R 280 Frame - 343034051
G2R 315 Frame - 361034031
10a M/CD DE END SHIELD (G1R) G2R 355 Frame - 361034035
132 FRAME G1S 132 SAE 3/4/5 362087014
SAE3 6036143033 G1R 160/SAE 3 - 361034009
SAE4 6036143046 G1R 160/SAE 2 - 361034021
SAE5 6035133057 G1R 160/SAE 4/5 361034025
160 FRAME G1R 200/SAE 2/3 - 361034011
SAE2 - 6049243023 G1R 250/SAE1/3 - 361034023
SAE3 - 6049243033 G1R 280/SAE 1 - 361034027
SAE4 6049243042 G1R 315/SAE 1 - 361034030
SAE5 6049243056 G1R 355/SAE 1 - 361034032
200 FRAME 54 TERMINAL BOX COVER
SAE 1 6069243013 132 Frame 361034019
SAE2 6069243023 160 Frame - 365031006
SAE 3 - 6069243033 200 Frame - 363031001

24 25
55 NDE VENT COVER 200 frame - 362031004
160 Frame - 362034006 301 DE BEARING
200 frame - 366034005 132 Frame - 6308.2Z 1 361123006
63 WOUND BOBBINS 160 Frame - 6310.2RS 1 369123002
G2S 312MR - 3ph(K6) 3 60311441 200 Frame - 6313.2RS 1 363123001
G2S 132MA -3ph (K8) 3 60321441 250 Frame - 6315 1 316121107
G2S 132MC -3ph (K10) 3 60341441 280 Frame - 6316 1 319121111
G2S 132MD -3ph (K12) 3 60351441 315 Frame - 6318 1 312121108
G2S 132LC -3ph (K15) 3 60361441 355 Frame - 6220 1 361121003
G2S 132MA -1ph (S5) 1 60321241 302 NDE BEARING
G2S 132MC -1ph (S6) 1 60341241 132 Frame - 6207.2Z 1 369123005
G2S 132MD -1ph (S8) 1 60351241 160 Frame - 6209.2RS 1 366123003
G2S 132LC -1ph(S10) 1 60361241 200 Frame - 6310.2RS 1 369123002
G2S 160SC -1ph(S12) 1 60451241 250 Frame - 6310.2RS 1 369123002
G2S 160MA -1ph(S15) 1 60471241 280 Frame - 6313.2RS 1 363123001
G2S 160SC -3ph(K20) 3 60451441 315/355 Frame - 6314.2RS 1 361123007
G2S 160MA -3ph(K25) 3 60471441
G2S 160MB -3ph(K30) 3 60491441 325 MAIN TERMINAL BOARD WITH
G2S 200SA -3ph(K40) 3 60611441 6 TERMINALS
G2S 200SB -3ph(K50) 3 60631441 132 Frame 1 367086013
G2S 200SD -3ph(K63) 3 60651441 160 Frame 1 36586003
G2S 200MD -3ph(K82) 3 60691441 200 Frame 1 369086002
250 Frame 1 369086028
65 COUPLING HUB 280 Frame 1 369086028
SAE 6.5/7.5 for 132 Frame - 6031243256 315 Frame 1 369086029
SAE 11.5 for 132Frame - 361041051 355 Frame 1 361087038
SAE 6.5/7.5 for 160 Frame - 6041243256
330 B/H ASSLY.
SAE 11.5 for 160 Frame - 6041243233
G2S/G1S 132/200 Frame 1 361241002
SAE 11.5 for 200 Frame - 6061243233
G2S/G1S 160 Frame 1 261241005
SAE 14 for 250 Frame - 361041045
SAE 14 for 280 Frame - 361041069 347 CABLE ENTRY GROMMET
SAE 14 for 315 Frame - 361041070 132 Frame 369086015
SAE 14 for 355 Frame - 361041076 160 Frame 364086011
66 COUPLING DISC SET 200 Frame 364086006
SAE 7.5 (Set of 2 Nos) 353 MOULDED RECTIFIER BRIDGE
for 132/160 - 361031038 G2S/G1S-132/160/200 - 3 Ph. 1 361260001
SAE 10 (Set of 2 Nos) G2S/G1S-132/160/200 - 1 Ph. 1 362260008
for 132/160 - 361031035 359 AUXILLARY TERMINAL
SAE 10 (Set of 3 Nos) BOARD ( 3 TERMINAL )
for 200/250 - 361031043 G2R/G1R 160 Frame 1 367086013
SAE 11.5 (Set of 2 Nos) G2R/G1R 200 Frame 1 365086003
for 132/160 - 361031033
371 DIODE BOARD ASSEMBLY
SAE 11.5 (Set of 3 Nos)
160/200/250/280 Frames 1 60692495
for G1R 200/250 - 361031034
315/355 Frame 1 67413245
SAE 14 (Set of 3 Nos)
for G1R 200/250 - 361031018 386 AVR SR 7/3 1 367260005
SAE 14 (Set of 4 Nos) AVR UVR - 6 1 361260013
for G1R 280 - 361031017 * CAPACITOR
SAE 14 (Set of 4 Nos) G2S/G1S 132 M(2MFD) 1 361260006
for G1R 315/355 - 361031042 G2S/G1S 132 L (0.5MFD) 1 361260009
71 COMPOUND PLATE G2S/G1S 160/200
132 Frame - 365031011 (Tapped Capacitor) 1 361260014
160 Frame - 364031009

26 27
 12 LEAD TERMINAL CONNECTIONS (Frame 160 / 200)
SERIES DELTA SERIES STAR PARALLEL ZIG-ZAG

W1
U W1 V4
V4 U4 W3
V2
W2 V3 V3
U3 W4
W3 V2 U3 U4
U2 W2 V1
W4 V1
U1 N U1 U2 L
U1 U2 U3 U4
B W1 V1
ROTOR WDG

Y W2 V2
W3 V3

R W2 U2 V2 V4
W4 VOLTAGE
'ARM' WDG 'L'WDG W UV
VOLTAGE VOLTAGE 240V (1Ph.)
W V
U1 V1 W1 240V 3Ph. 415/240V 3Ph.
B
U4 V1 V4 W1 W4 U1 U1 U3 V1 V3 V2 V4 W1 W3
Y
W3 W3

'AUX'WDG R 'C' WDG W2 W2

V3 V3
U1 V1
V2 V2
ROTOR STATOR CONNECTORS CE UNIT U3 U3
Red U2 U2
Blue MAIN TERMINAL
Cable
Cable + BOARD
U4 V4 W4 U2 U4 W4 W2
DC AC

MOV - U V W U V W L N
BRIDGE
RECTIFIRE R : Red Cable
CAPACITOR Y : White Cable NOTE:-ADJUST ' VOLT' POTENTIOMETER OF AVR (IF REQD) TO GET REQUIRED VOLTAGE
B : Blue Cable

12 LEAD TERMINAL CONNECTIONS 12 LEAD TERMINAL CONNECTIONS

(Frame 250/280/315/355) (Frame 160/200)
PARALLEL DELTA PARALLEL STAR PARALLEL DELTA PARALLEL STAR
U U
W3 V2 W3 V2
U2 U4 V4 U2 U4
V4
W1 W1
W4 V1 W4 V1

W2 U3 U4 V3 U1 U3 W2 U3 U4 V3 U1 U3
W3 V1 W3 V1
U1 U2 U1 U2 W1
W1
V3 V3
ROTOR WDG

W4 V2
'ARM' WDG 'L'WDG
W4 V2
PH N
W
W2 V4 V W
W2 V4 V
VOLTAGE VOLTAGE VOLTAGE VOLTAGE
W U V W U V
240V (3Ph.) 415/240V (3Ph.) 240V (3Ph.) 415/240V (3Ph.)

'AUX'WDG 'C' WDG MAIN TERMINAL

U1 U3
U2 U4 V2 V4 W2 W4 V1 V3
V1 V3 W1 W3 U1 U3 U2 U4 V2 V4 W2 W4
V1 V3 W1 W3 U1 U3
BOARD W3
ROTOR STATOR CONNECTOR CE UNIT
W1
V3
Red V1
Blue Cable U3
Cable + U1

DC AC

MOV
- U2 U4 V2 V4 W2 W4 W1 W3
U2 U4 V2 V4 W2 W4

BRIDGE
RECTIFIRE U V W U V W N U V W N U V W
CAPACITOR

NOTE:-ADJUST ' VOLT' POTENTIOMETER OF AVR (IF REQD) TO GET REQUIRED VOLTAGE

28 29
 Exploded View
Alternator G2S/G1S 132
30

Exploded View
Brushless Alternator
31
 CONNECTION DIAGRAM OF G2R/G1R FRAMES 160/200

Hz (UFRO)
AMP (OL)
1 PH BRUSHLESS ALTERNATOR

VOLT.
STAB

DRP
EXCITER

OV
OL
UF

SL
ROTOR STATOR
STATOR
RECTIFER ARMATURE
EXCITER WINDING
ARMATURE BRIDGE

EXCITER FIELD
AVR (UVR-6 ,SPS) CONNECTION DIAGRAM

S UPP RE SO R
NEUTRAL PHASE

MAIN FIELD
S URG E
OVM - OVER VOLTAGE TRIP MODULE
AVR-SR 7/3

100K or Link
7
6
60HZ
INDICATOR
SF
UF
} 5
5
LEAD 4 4
OL SR7/3
AMP 3 Cable Marker
(UFRO) Hz +VE

FUSE 4 AMP
2
STAB 3
1
VOLT. -VE
1
Blue Cable

Red Cable

UF - UNDER FREQUENCY INDICATION

10

11

12
4

9
1

OV - OVER VOLTAGE INDICATION

OL - OVER LOAD INDICATION.

SL - SENSE LOSS INDICATION
CONNECTION DIAGRAM OF G2R/G1R FRAMES 160/200/250
3 PH BRUSHLESS ALTERNATOR WITH AUXILIARY WINDING
+
-

EXCITER
F1
F2

Marker
UC2
VC2

Cable

ROTOR STATOR
100K OR LINK

STATOR
}
Q1

Q2

RECTIFER
60HZ

80-480 Vac
EXCITER
BRIDGE
}

SENSING ARMATURE
ARMATURE

EXCITER FIELD
FIELD
N WINDING
DROOP

TO OVM

EXCITER

SUPPRESOR
U
`CT'.

160-270 Vac

MAIN FIELD
TO

SURGE
SUPPLY
V

AUX.WINDING

Blue Cable

Red Cable
AVR-SR 7/3

100K or Link
7
6
60HZ
Cable Marker
INDICATOR
SF
UF
} 5
5
LEAD 4 5
OL 4
SR7/3 3
AMP 3
(UFRO) Hz +VE 3
2
STAB
1 1
VOLT. -VE

Blue Cable

Red Cable

32 33
AUTOMATIC VOLTAGE REGULATOR : ADJUSTMENT PROCEDURE :
AVR SR 7/3 & UVR 6 CAUTION : IT IS HAZARDOUS TO PROCEED FOR HIGH VOLTAGE
GENERAL : TEST ON THE ALTERNATOR WITHOUT HAVING PREVIOUSLY
DISCONNECTED ALL CONNECTIONS TO AUTOMATIC VOLTAGE
The PC Board with eletronic components is located inside a box and
REGULATOR (AVR). DAMAGES OCCURING TO AVR IN SUCH
embedded in elastomer resin. Terminal consist in 1/4" “Fasten” lugs.
CONDITIONS WILL NOT BE CONSIDERED IN WARRANTY CLAIM.
CONNECTIONS :
Alternators equipped with particular AVR is thoroughly tested and
Connection to the AVR should be made as per schematic diagram calibrated in test rig at our works. If required following Adjustment
shown in the Fig. procedures to be followed for normal operation during
POTENTIOMETER DESCRIPTION : commissioning or in subsequent operation.
‘VOLT’ Voltage Adjustment Pot ADJUSTMENT OF ‘HZ’ POTENTIOMETER :
‘STAB’ Stability Adjustment Pot
‘Hz’ Under Speed Protection Adjustment Pot Operating on the ‘Hz’ Pot. we have the possibility to correct the
‘AMP’ Over Excitation Adjustment Pot frequency corner of the low speed protection. To modify this calibration
one must operate in the following way :
FUNCTIONS OF THE AVR POTENTIOMETER : a) Rotate the Hz pot. fully clockwise with generator at its nominal
VOLT : speed at no load;
This potentiometer allows to adjust the terminal voltage of the alternator. b) Decrease the rotating speed until the desired operating point of
Its adjustment range is very simple. Therefore we suggest adjust it the protection (48 Hz for 50 Hz operation) and then rotate the
with care. Rotating the Pot. clockwise the voltage increases, Hz pot. In counterclockwise direction till voltage decreases of
counterclockwise the voltage decreases. 1.5% approximately;
STAB : c) Seal the Hz pot.
It allows optimizing the alter nator’s response time. Rotating d) Raise the gen-set speed to its nominal value
counterclockwise the stability is decreased, the response times become
short but the voltage is less stable. Rotating it clockwise, the respose
time is longer but the voltage is more stable.
415 V
Adjust the STAB potentiometer in such a way that oscillations do not

Terminal Voltage
occur and the damping is as desired.
HZ :
Hz potentiometer is used to adjust the level of intervention of the low
frequency protection.Usually this adjustment is performed by the
manufacturer during testing and then sealed.
Frequency 48 50 Hz
AMP :
This potentiometer allows adjusting the level of intervention of the Threshold for
overexcitation protection. This protection system has a delay, which under speed protection
permits temporary overloading of the machine during star t-up of
electric motor or for other purposes.
34 35
ADJUSTMENT OF ‘AMP’ POTENTIOMETER : DIMENSIONAL DRAWING FOR "SLIPRING (G2S)" &
This potentiometer, that is normally calibrated and sealed in our "BRUSHLESS (G2R)" TYPE (FRAMES : 132, 160 & 200)
factor y, ser ves to calibrate the inter vention threshold of the
overexcitation protection.
L±5
AC
The factory adjustments corresponds to the excitation current for a X - CG OF M/C L1
sustained three-phase short circuit of about three times the rated current, AIR OUT-LET
unless otherwise specified. (In many countries the short- circuit current
equal to three times the rated one is obligatory in order to allow selective
tripping of circuit breakers.)
For its clibration you must operate in following way :

HD
HC
a) With alternator at no load and at nominal speed rotate the ‘AMP’

H
pot. Fully clockwise.
b) With full load operate on the ‘VOLT’ pot till to obtain an excitation AA 2 HOLES ØJ

HA
A±0.5 AIR IN-LET
voltage (in D.C. measured between 1 (-) & 3(+) terminals of the BB
AB
regulator) equal to the 110% of nominal one at full load. GD E
±0.5
C
±0.5
BS±0.5
N HOLES øK

At this point check and note the output voltage of the alternator. G BM±0.5

F
BL ±0.5
c) Turn the ‘AMP’ pot. fully counterclockwise.

øD
d) After about 20 seconds the voltage decreases considerably ‘M’ TAPPED HOLE

e) Operate immidiately on the ‘AMP’ pot. in clockwise sense till

when the output voltage of the alternator arrives at a value 2%
lower than the one read and noted at point (b)
FRAME A AA AB AC BB BS BM BL C D E F G GD H HA HC HD N K L L1 M X
G2R G2S
f) Discharge the alternator to no load and operate on the ‘VOLT’ 132 MR 70 284

pot. So as to reestablish the output voltage of the alternator to 132 MA 77 299

38.018
38.002

132.0
131.5
132 MC - 86 206 56 256 272 122 316 372 - 45 80 10 32.8 40.8 12 260 365 4 12 581 322
its rated value. 132 MD 94
296 M12
339
132 LC 105 371 427 6 636 344
P) Seal the ‘AMP’ pot. 160 SA 121 - 335
160 SB 131 - 196 197 292 - 4 658 350

48.018
48.002

160.0
159.5
160 SC 141 132 270 70 340 350 66 110 14 42.5 51.5 16 323 418 15 300 360
42.3 51.3
REMOTE REGULATION OF THE VOLTAGE : 160 MA 166 157 400
160 MR 174 - 306 197 307 402 6 768 410
Obtained by application of a 100 KW potentiometer between the 160 MB 186 177 420

terminal 5 & 7 permitting a regulation of ±5% of the nominal voltage. 200 SA 217 204 400
200 SB 236 223 225 280 400 - 4 830 420
200 SC 250 - 435

60.030
60.011

200.0
199.5
53.0
200 SD 264 251 340 75 410 424 57 140 18 52.8 64.0
63.8 20 403 510 19 350 M20 450
200 MD 335 322 520
325 270 380 500 6 930
200 MDX 342 - 525

36 37
 OUTLINE DIMENSION DRAWING FOR
OUT-LINE DIMENSION DRAWING FOR DOUBLE BEARING ALTERNATOR "SLIPRING (G1S)" TYPE
FRAME : 250/280/315/355 SINGLE BEARING (B2) CONSTRUCTION
FRAME : G1S132, 4 POLE & 2 POLE
AC REMOVABLE SIDE COVERS L1

CG- X

AVR
M WA±0.5 A
AIR OUT-LET
262 SP CG
9
AIR OUTLET
HD

HC

PA 0.02
-0.05
AIR INLET

365

Ø160
H

N
P

132-0.5
Ma

-0
AA BS
HA

±0.5 AIR IN-LET

A±0.5 CRS E C±1 BM±0.5 CRS
AB GD
BB N HOLES øK 0
G 206 CRS 4 HOLES OF ø12
L±5 122
F

B±0.5 56
`N1' Nos.° HOLES `N' Nos.HOLES øS
øD

OF `S1' DIA. 2-PLATE COUPLING

M TAPPED HOLE
TOTAL THICKNESS 4MM
HUB SECURING BOLTS TO BE TIGHTNED
TO TORQUE OF 8Kg-m
DIMENSIONS in Milimeters
M/C WT.
FRAME
(Kg) A AA AB AC BB BS BM C ØD E F G GD H HA HC HD N ØK L L1 ØM X

250 MB 465 510 ALL DIMENSION IN mm

70.030
70.011

990
250.0
249.5

250 MC 475 406 75 476 510 470 203 406 168 140 20 62.5 74.5 17 495 750 415 M20 530 TYPE MR MA MB MC MD LC
62.3 74.3
250 MD 525 1050 555 DIMENSIONS - mm
280 SA 570 435 184 368 980 540
A 584 575
280 MB 615 485 209.5 419 6 24 550
75.030
75.011

280.0
279.5

67.5 79.5 B 380 371

280 MD 650 457 75 527 560 190 140 20 22 560 780 1065 415 M20 560
67.3 79.3
280 LB 705 525 228.5 457 1150 580 CG 194 209 219 232 249 254
280 LD 740 610
315 SA 890 460
315.00
314.50

COUPLING DISC
80.030
80.011

71.0 85.0 SAE SAE FLANGE

315 SB 980 508 75 635 640 520 228.5 457 216 170 22 27 620 850 1220 450 M20 480
70.8 84.7 N S SP
N1 No N (h7) P M
315 MB 1050 6 28 1320 520 No PA Ma S1 1 WA
HOLES 5 314.3 356 333.4 8 11 45° 3.5
355.00
354.50
95.035
95.013

355 SB 1175 86.0 100 660

610 75 670 685 570 250 500 254 170 25 27 706 980 1360 560 M24 6 1/2" 215.9 200 6 9 60° 30.2
355 SC 1325 85.8 99.8 702 4 362 405 381 12 11 30° 5

355 MA 1620 1460 750 7 1/2" 241.3 222.3 8 9 45° 30.2 3 409.6 450 428.6 12 11 30° 5
8" 263.52 244.5 6 11 60° 62
10" 314.32 295.3 8 11 45° 53.8
11 1/2" 352.42 333.4 8 11 45° 39.6

38 39
 OUTLINE DIMENSION DRAWING FOR SINGLE BEARING ALTERNATOR OUTLINE DIMENSION DRAWING FOR SINGLE BEARING ALTERNATOR
FRAME : 160 FRAME : 200

±0.5 ±0.5 ±5
WA
±5
A ØM WA A
350 5 CG 300 15° 15° 5 CG 350
WB 12 HOLES Ø11

12 AIR OUT-LET WB AIR OUT-LET

N° HOLES ØS1 12
øM

510
418

Ø163

Ø163
ØPA
ØPA
1

ØN
ØP
ØN
ØP

-0.5

-0.5
0
-0

160

200
AIR IN-LET
øMa 2-PLATE COUPLING N0 HOLES Ø15 AIR IN-LET
TOTAL THICKNESS 2.4mm ØMa N° HOLES Ø19
±0.5 ±1 ±0.5 ±0.5 3-PLATE COUPLING
270 HUB SECURING BOLTS
TO BE TIGHTENED TO C B 95 340 ±0.5 TOTAL THICKNESS 3.6mm ±0.5 ±0.5
±1
N° HOLES ØS TORQUE OF 24.9 kgfm (244 Nm) HUB SECURING BOLTS C B 120
TO BE TIGHTENED TO
N° HOLES ØS TORQUE OF 24.9 kgfm (244 Nm)

DIMENSIONS in Milimeters DIMENSIONS in Milimeters

TYPE 160SA 160SB 160SC 160MA 160MR 160MB SAE FLANGE COUPLING DISC SAE FLANGE
TYPE 200SA 200SB 200SC 200SD 200MD 200MDX COUPLING DISC
A 578 688 No øN øP N° øM øS SAE No
HOLES øN øP øM
B -- 110 A 716 816
5 314.3 k6 356 333.4 8 11 45° 6 1/2"-7 1/2"-8" 3 409.6 k6 450 428.6 8" - 10" - 11 1/2"
293 293 B -- 110
C 4 362 k6 405 381 12 11 30° 6 1/2"-7 1/2"-8"-10" 2 447.7 k6 490 466.7 10" - 11 1/2"
CG 205 220 230 275 285 295 3 409.6 k6 450 428.6 12 11 30° 8"-10"-11 1/2" C 363 353
1 511.18k6 550 530.2 11 1/2" - 14"
2 447.7 k6 490 466.7 12 11 30° 10"-11 1/2" CG 280 300 315 330 370 400
N° HOLES 4 6
COUPLING DISC
ø 15 N° HOLES ø19 4 6 SAE
SAE COUPLING DISC N°
No ø PA -0.02 ø Ma N° HOLES øS1 1 WA WB ROTOR WT. (Kg.)
79.5 90.5 96 101.5 133.5 138.5 No øPA øMa HOLES
øS WA WB
ROTOR WT. 36 42 47 57 61 66 -0.04
WITHOUT DISC
WITHOUT DIMENSIONS in mm 8" 263.52 244.5 6 11 60° 62 -
DISC (Kg.) 6 1/2" 215.9 200 6 9 60° 30.2 18
10" 314.32 295.3 8 14 45° 53.8 -
7 1/2" 241.3 222.3 8 9 45° 30.2 18 WITHOUT DISC 0.37 0.43 0.49 0.52 0.70 0.72
ROTOR GD2 0.16 0.19 0.21 11-1/2" 352.42 333.4 8 11 45° 39.6 9
0.24 0.26 0.29 (Kg.-m2 )
WITHOUT 8" 263.52 244.5 6 11 60° 62 - 14" 466.72 438.2 8 14 45° 25.4 23.2
DISC
(Kg.-m2 ) 10" 314.32 295.3 8 11 45° 53.8 -
11 1/2" 352.42 333.4 8 11 45° 39.6 8 COUPLING DISC
M/C WT. (Kg.) 7-1/2" 8" 10" 11-1/2" 14"
SAE NO.
TYPE 200SA 200SB 200SC 200SD 200MD 200MDX DISC WT.
M/C WT. (Kg.) COUPLING DISC 5.8 6.2 7.3 8.5 12.7
6-1/2" 7-1/2" 8" 10" 11-1/2" (Kg.)
TYPE 160SA 160SB 160SC 160MA 160MR 160MB SAE NO. SAE2
220 239 250 267 342 348
DISC WT. SAE3 2
SAE2-11/5" 3.6 3.9 4.7 5.2 7.2 DISC GD
124 134 144 169 177 189 (Kg.) 0.024 0.030 0.053 0.079 0.225
SAE3-11.5" SAE1 224 243 254 271 346 352 (Kg.-m2 )
DISC GD2
SAE4-7.5" 119 129 139 164 172 184 0.023 0.028 0.030 0.050 0.060
SAE5-7.5" (Kg.-m2 )
NOTE: THE GD2 VALUE AND ROTOR WT. OF SINGLE BEARING ROT0R (WITH DISC) IS OBTAINED
BY SUMMING THE GD2 VALUE & ROTOR WT. OF WITHOUT DISC ROTOR WITH THE GD2 VALUE
AND DISC WT. OF THE CHOSEN SAE COUPLING DISC.
NOTE: THE GD2 VALUE AND ROTOR WT. OF SINGLE BEARING ROT0R (WITH DISC) IS OBTAINED
BY SUMMING THE GD2 VALUE & ROTOR WT. OF WITHOUT DISC ROTOR WITH THE GD2 VALUE
AND DISC WT. OF THE CHOSEN SAE COUPLING DISC.

40 41
OUT-LINE DIMENSION DRAWING FOR SINGLE BEARING ALTERNATOR
FRAME : 250/280/315/355

AC REMOVABLE SIDE COVERS LI

WA±0.5 X -CG
AVR
R HOLES øS
ON M PCD AIR OUT-LET
HD

øPA
=

øQ

øN
øP
=

AA HA
BS±0.5
A±0.5 C±1 BM±0.5 AIR IN-LET

AB R1 HOLES øS1 BB
ON M1 PCD N HOLES ØK
L±5
3-PLATES COUPLING FOR G1R250
TOTAL THK. 3.6MM
4-PLATES COUPLING
TOTAL THK. 4.8MM FOR G1R280/315/355
HUB SECURING BOLTS TO BE TIGHTENED
TO TORQUE OF 24.Kg-m FOR M16 & 48 Kg-m FOR M20

DIMENSIONS in Milimeters
M/C WT.
FRAME (Kg) A AA AB AC BB BS BM C H HA HD N ØK L L1 X
250 MB 465 350
900
250.0
249.5

250 MC 475 406 75 476 510 520 203 406 220 17 750 6 415 360
250 MD 535 960 415
280 SA 570 435 184 368 860 400
280 MB 615 485 209.5 419 24 945 410
280.0
279.5

280 MD 650 457 75 527 560 215 22 780 6 415 420

280 LB 705 525 228.5 457 440
1030
280 LD 740 470
315 SA 890 460
355.0 315.00
354.5 314.50

1100
315 SB 990 508 75 635 640 520 228.5 457 237 27 850 450 480
315 MB 1060 6 28 1200 520
355 SB 1175 550
610 75 670 685 570 250 500 297 27 980 1240 560
355 SC 1325 570
355 MA 1615 1340 620

FLANGE COUPLING DISC

SAE SAE
ØQ ØPA -0.02 M1 R1 ØS1 1 WA
No ØN ØP M R ØS No -0.04

250 280 315 355 DIMENSIONS in mm

3 409.6 450 428.6 494 550 - - 12 11 30° 10" 314.32 295.3 8 11 45° 53.8
2 447.7 490 466.7 494 550 620 - 12 11 30° 11 1/2" 352.42 333.4 8 11 45° 39.6
1 511.18 553 530.4 554 550 620 706 12 12.5 30° 14" 466.72 438.2 8 13.5 45° 25.4
0 647.6 711 679.5 - - 620 706 12 14 30° 18" 571.4 543 8 16.7 45° 15.87

42