Northern Lights OPX300K2 User manual

OPERATOR’S MANUAL
OPERATOR’S MANUAL
OPX300K2
For PX-K2 and C2 series A.C. generator ends
www.northern-lights.com

Breathing Diesel engine exhaust and some of its constituents
are known to the State of California to cause cancer, birth
defects, and other reproductive harm.
* Always start and operate the engine in a well-ventilated area.
* If in an enclosed area, vent the exhaust to the outside.
* Do not modify or tamper with the exhaust system.
* Do not idle the engine except as necessary.
For more information, go to www.P65warnings.ca.gov/diesel.
— CALIFORNIA —
Proposition 65 Warning:
Northern Lights
4420 14th Avenue NW
Seattle, WA 98107
Tel: [phone]
Fax: [phone]
Copyright ©2018 Northern Lights, Inc.
All rights reserved. Northern Lights™, and
the Northern Lights logo are trademarks of
Northern Lights, Inc.
Printed in U.S.A.
PART NO.: OPX300K2 07/18

OPX300K2 2/18
3
OPERATOR’S &
PARTS MANUAL
PX-300K2 SERIES A.C. GENERATORS
For Generator Models:
PX-308K2, PX-309K2, PX-310K2, PX-312K2, PX-316K2,
PX-320K2, PX-320C2, PX-325K2, PX-332K2, and PX-332C2
Read this manual thoroughly before starting your equipment.
This manual contains information needed to operate your set correctly and safely.
Introduction......................................................................4
Safety Rules .....................................................................4
Models and Serial Numbers ...........................................5
Mechanical Construction .................................................6
INITIAL INSPECTION AND COUPLING
Initial Inspection..........................................................6
Coupling with Prime Mover........................................6
Grounding ...................................................................6
PERFORMANCE AND FUNCTION
Excitation System........................................................7
Automatic Voltage Regulator (AVR) ..........................7
Under Speed Protection...............................................7
Rotary Rectier and Surge Suppressor .......................7
CHARACTERISTICS
Voltage Regulation ......................................................8
Response .....................................................................8
Voltage Stability ..........................................................8
Motor Starting .............................................................8
Short Circuit................................................................8
Phase Rotation.............................................................8
STANDARD VOLTAGE SELECTION TABLE .....8
OPERATION - GENERATOR SET
Starting........................................................................9
Voltage Adjustment.....................................................9
Running.......................................................................9
Stopping......................................................................9
OPERATION - VOLTAGE REGULATOR
Safety Rules ............................................................. 10
Operation ................................................................. 10
Adjustment............................................................... 10
MAINTENANCE
Bearing Inspection ....................................................11
Insulation Resistance Measurement Method ............11
Rotating Rectier Assembly ....................................11
Parts Replacement Method ...............................11 - 12
Automatic Voltage Regulator Maintenance............. 13
SPECIFICATIONS
Generator Specications.................................. 14 - 15
Voltage Regulator Specications............................. 16
TROUBLESHOOTING ......................................... 17
PARTS LIST ..................................................... 18 - 26
WIRING DIAGRAM
AVR DST-100-2FAK ............................................. 27
Table of Contents
Proprietary Information
This publication is the property of Northern Lights, Inc.
It may not be reproduced in whole or in part without the written permission of Northern Lights, Inc.
© Northern Lights, Inc. 2014. All rights reserved. Litho U.S.A. Publication number OPX-300K2 04/14

OPX300K2 2/18
4
Introduction
This manual describes procedures for operation,
maintenance, inspection and adjustment. It will help the
operator realize peak performance through eective,
economical and safe operation.
• Read this manual carefully BEFORE operating the
generator.
• Study this manual until proper operation becomes
personal habit.
• Operation, inspection, and maintenance should be
carried out carefully. Safety must be given the rst
priority.
Safety Rules
• To insure years of trouble-free operation, the
specied maintenance is important and should be
performed.
• Electrical equipment should always be kept
clean. Oil, dust, moisture and salt are all harmful
to generators.
• Be careful with electricity. Do not touch rotating
parts.
• Ambient Environmental Conditions
a) Gas: Do not use in an environment of corrosive
or ammable gas (gasoline, hydrogen sulde,
methane gas, etc.)
b) Sandy Dust: Do not use equipment in places
with excessive sand and dust.
c) Humidity: Do not use in very humid
environments for long periods of time.
d) Salt/Seawater: Protect your generator from
exposure to salt, water, and water vapor.
• Insulation Resistance and Dielectric: When
measuring insulation resistance and dielectric, be
sure to disconnect the AVR and rectier.
• Be sure that the regulator is shut o by switching the
CPR (circuit breaker) on the AVR to the o position
when the unit is running at less than rated speed, or
when the unit is to be run but no power generation is
required.
• Before starting your generator, be sure operating
conditions are safe.
• Ventilation: When selecting the installation site, be
sure that the area is well ventilated and that ambient
temperature does not exceed 40°C. If the
temperaure exceeds 40°C, de-rate the generator
output as per “data sheet” for operation.
• Be sure to provide generator with cover and
protection when operating outside.
PX-300K2 Series AC generators are based on
BS 4999 part 20 and IEC34-5, IP21.

OPX300K2 2/18
5
AC Generator Data
Generator Set Data
Northern Lights, Inc., WA USA
www.northern-lights.com
Model No.
Serial No.
DUTY
KW
KVA
RPM
HERTZ
PHASE
°C RISE
RULE
WIRE
INSUL
AMB°C
PF
VOLTS
VOLTS
AMPS
AMPS
Set Serial
Set Model
Model and Serial Numbers
GENERATOR END MODEL NUMBERS
Generator Set Model No ................ PXK Generator Model
M and NL753W2 ..........................................PX-308K2
M and NL773LW2 / LW3 ..............................PX-309K2
M and NL843JW ..........................................PX-310K2
M and NL843NW2 / NW3.............................PX-312K2
M844W2 / W3 ..............................................PX-316K2
M844LW2 / LW3 ..........................................PX-320K2
M20CRW2/ CRW3 .......................................PX-320C2
M864W / W3 ................................................PX-325K2
M944W / W3 ................................................PX-332K2
M30CW / CW3 .............................................PX-332C2
M984W.........................................................PX-332K2
M33CW ........................................................PX-332C2
SERIAL NUMBERS
• When referencing Northern Lights equipment by serial
number, it is important to dierentiate between the engine,
generator end, and generator set serial numbers.
• The engine serial number is either on a metal tag or stamped
directly into the engine block.
• The generator END serial number is on a metal tag attached
to the generator end.
• The generator SET serial number is on a separate metal tag
attached to the generator end. It may be a ve by one inch tag
installed directly below the generator end tag. Or, it may look
like the illustrations below. Please use the generator SET number
in correspondence or when ordering parts.
Figure 1: Generator Set Serial Number Plate

OPX300K2 2/18
6
Mechanical Construction
STATOR
The stator frame is fabricated from rolled steel. The
round construction provides rigidity and strength to
resist excessive mechanical shocks. The stator core is
made of high quality silicon steel plates coated with
insulating lm for prevention of eddy currents. The
core is positioned along the internal surface of the
frame. The exciter eld core is made of special steel
plates capable of retaining a high degree of residual
magnetism.
BEARINGS
The long-life ball bearings are sealed to prevent grease
from escaping and to keep dirt out.
ROTOR
The rotor shaft is made of high quality carbon steel,
and is designed and manufactured to be mechanically
durable. The rotor is a salient revolving eld type
with the main eld core made from special steel plates
having superior magnetic characteristics. The eld
core elements, exciter rotor, rotary rectier and
cooling fan are integral parts of the same shaft.
VENTILATION
Cooling is provided by the cooling fan of the rotor
through suction ports and exhausted through outlet
ports. Every machine conforms to the cooling code
ICO1 of BS.
Initial Inspection and Coupling
INITIAL INSPECTION
If the generator is stored for long periods of time, store
in a clean, dry, ventilated area. After extensive stor-
age time, check the resistance of the coil insulation in
accordance with this manual (see MAINTENANCE,
page 11) before operation. Be sure there are no abnor-
mal sounds or any overheating during operation. It is
recommended that standby generators utilize a space
heater (optional) in order to keep the coil insulation in
optimum working condition.
COUPLING WITH PRIME MOVER
PX-300K series single bearing generators make
centering and direct coupling easy. Coupling bolt size
and torque will vary according to the engine
manufacturer.
GROUNDING
The generator frame should be electrically grounded
to the base of the generator set. The neutral is not
grounded to the frame unless specied.

OPX300K2 2/18
7
Performance and Function
EXCITATION SYSTEM
The excitation system of the PX-300K Series generator uses
an Automatic Voltage Regulator (AVR) which uses a portion
of the output power to supply controlled DC power to the
exciter eld (EX) as show in Figure 2. When DC power is
supplied to the exciter eld, output from the exciter armature
is rectied by a 3-phase bridge rotary rectier (Si) and
supplied to the main eld coils. See Figure 2.
AUTOMATIC VOLTAGE REGULATOR (AVR)
The PX-300K2 Series generators use a DST-100-2FAK
AVR. This is a compact voltage regulator for generators
with an output up to 50kW. The AVR can be used in 120V
single phase applications and is installed inside the generator
junction box.
The AVR obtains sensing input from the main stator coils
and compares the rectied value of the sensing voltage with
the reference voltage produced inside the AVR. Input power
is obtained from the main stator.
Rectied output power to the exciter eld is controlled by
switching a transistor on and o. This AVR will control
terminal voltage even if the input sine wave is distorted.
Figure 2: PX-300K2 Block Diagram
AVR: Automatic Voltage
Regulator
EX: Exciter
Si: RotatingRectier
Figure 4: For 60 Hz
Figure 3: For 50 Hz
UNDER SPEED PROTECTION
A frequency sensing circuit is built into the AVR.
When the generator speed drops to 90% of rated
speed this circuit protects the AVR by reducing
the voltage in proportion to the decrease in engine
speed. In addition, when the generator is hit with a
rapid overload, this circuit will lower the voltage to
protect the engine. See Figures 3 & 4.
ROTARY RECTIFIER AND SURGE
SUPPRESSOR
The rotary rectier assembly, consisting of six
diodes, functions as a 3-phase full wave rectier for
the output of the exciter armature and supplies this
to the main eld. To protect the diodes from large,
instantaneous voltage surges, surge absorbers are
provided as part of the rotating rectier assembly.

OPX300K2 2/18
8
Characteristics
VOLTAGE REGULATION
Generator terminal voltage regulation is within ±1% of the
rated voltage in lagging power factor. 1.0 to 0.8, when the
load is varied gradually from no load to full load. This value
includes the temperature drift and rotating variation.
RESPONSE
After supplying a load instantaneously, the generator voltage
should be restored to the steady condition in accordance with
BS4999 Part 40, grade VR2.11 to VR2.23.
VOLTAGE STABILITY
In constant load and engine speed, voltage stability remains
0.25% of the rated voltage.
Winding Connection Frequency Voltages
3 Phase Series Star 60 Hz 480/277 460/266 440/254 416/240
(High Wye) 50 Hz 415/240 400/231 380/219
3 Phase Parallel Star 60 Hz 240/139 230/133 220/127 208/120
(Low Wye) 50 Hz 208/120 200/115 190/110
1 Phase 60 Hz 120/240
60 Hz 120
1 Phase 50 Hz 100/200 110/220 115/230 120/240
50 Hz 110
SHORT CIRCUIT
PX-300K2 Series AC generators can provide over 300%
of the rated current for 10 seconds at a powerfactor of 0.
PHASE ROTATION
Phase sequence is T1-T2-T3 (U-V-W, A-B-C) with a
counterclockwise rotation of generator viewed from the
anti-coupling side.
Figure 5: Standard Voltage Table
Standard Voltage Tables and Connection Diagrams
Standard voltage selection table and connection diagram for PX-300K2 Series 1-phase 4-wire and 3-phase 12-wire AC
generators.
Updated 3-24-14

OPX300K2 2/18
9
Operation – Generator Set
STARTING
Before starting generator, check the following:
1. Make sure that the wiring is correct.
2. Be sure that nothing is blocking the air inlet/ outlet.
3. Make sure that the inside of the generator is clean.
4. Be sure the main line circuit breaker is switched
OFF.
After checking each of the above, start the generator in the
following procedure:
1. Start engine in accordance with instructions in the
Operator’s Manual. Be sure there is no abnormal
sound or vibration.
2. The voltage will rise due to the increase in generator
speed.After making sure that each interphase voltage
is balanced, set the voltage and frequency to the rated
level. Be sure the CPR switch is “ON”. The voltage
will not rise with CPR “OFF”.
3. After running the generator without load, switch the
circuit breaker ON to start the load operation.
VOLTAGE ADJUSTMENT
The generator has been adjusted to obtain optimum
voltage at the factory. If the voltage is dierent, adjust
the voltage with the Voltage Adjust provided on the
AVR.
CAUTION: Excessive non-linear loads can
lead to regulator and/or generator end failures
and should be no greater than 20% of overall
load. Failures caused by excessive non-linear
loads are not warrantable.
RUNNING
Check the following while operating the generator:
1. Abnormal vibration and/or sound
2. Load
3. Environment:
Keep the air inlet/outlet clean and clear for optimum
cooling. Insucient cooling causes over heating of the
generator.
Note: When a 3-phase generator is used at single phase
load, each phase current should be balanced and should
not exceed 50% of the rated current. In addition,
allowable unbalanced load is listed on the Data Sheet.
STOPPING
After putting the running generator in a no-load condition
by removing the generator load, stop the engine in
accordance with the Engine Manual.
Updated -5-7-21

OPX300K2 2/18
10
Operation – Automatic Voltage
Regulator
SAFETY RULES
• DonotleaveAVRconnectedwhentestinggenerator
with high-pot or megger.
• Adjust the engine only when the CPR is in “OFF”
position.
OPERATION
1. Make sure the wiring is correct.
2. Make sure the frequency selection switch is set to
the rated frequency (60 or 50 Hz).
3. To adjust the voltage turn the Voltage Adjust
(VR1) counter-clock wise. Make sure the CPR is
“ON”.
a. Start the engine with no load and increase the
engine speed slowly to the rated level.
The voltage willautomaticallybuild up (residual
voltage: more than 10V).
b. Adjust to the rated voltage using the Voltage
Adjust (VR1).
c. Make sure of the proper Volt/Frequency
characteristic by reducing the generator speed.
d. Make sure of voltage stability by switching the
load “ON” or “OFF”. Use the Stability Adjust
(VR2).
e. If you nd no problem with the AVR, start the
normal operation.
ADJUSTMENT
Each component of the AVR is adjusted at the factory
to obtain optimum voltage. If readjustment is
necessary, make sure the voltage, frequency, load, etc.
are functioning properly after readjustment.
1. Initial Excitation: For initial excitation use a
DC12V or DC24V battery.
a. Stop the generator.
b. Remove the AVR connectors.
c. Connect the eld terminal F(+) with the
polarity (+) of battery and the terminal F (-)
with the polarity (-) and excite AVR eld for 2
or 3 seconds.
2. Voltage Adjustment:
If the voltage output is low, increase the voltage by
turning the Voltage Adjust (VR1) slowly clockwise.
3. Stability:
If the voltage output is unstable, increase the voltage
by turning the Stability Adjust (VR2) clockwise.
4. Voltage and Frequency:
Voltage and Frequency (Hz) have been preset at the
factory.

OPX300K2 2/18
11
Maintenance
BEARING INSPECTION
For bearing inspection, make sure that there is no
abnormal sound during normal running and no over-
heating. Greasing is not necessary for generators using
the double seal type ball bearings, but these will need to
be replaced after every 10,000 hours of operation (see
PARTS REPLACEMENT METHOD).
INSULATION RESISTANCE MEASUREMENT
If the generator has not been used for a long time, check
the insulation resistance of each lead wire at 500V with a
megger.
It is usually enough to check only the stator winding. In
order to prevent damage to the AVR, disconnect it. If the
measured insulation resistance value is above 2 M ohms,
there is no problem, but if it is lower than that, check to
see if the inside of the generator is wet or dirty. If dust has
accumulated, blow it out with dry compressed air. Wipe
o oil stains with a cloth. If the generator is damp, dry it
and re-check.
ROTATING RECTIFIER ASSEMBLY
The rotating rectier assembly needs little attention.
Clean o dust and oil stains periodically. In the unlikely
event that it becomes necessary to replace the diode ele-
ments and surge absorber elements. Refer to PARTS
REPLACEMENT METHOD.
PARTS REPLACEMENT METHOD
1. Bearing Replacement:
a. In order to replace the bearing, rst remove the
bearing holder housing on the end of the
generator. Loosen and remove the four housing
bolts. Remove the bearing holder gently since
there is a risk that the rotor could fall and damage
the exciter rotor or the exciter stator.
Figure 6. Pilot Length
b. Using a bearing puller, extract bearing from
shaft.
c. When installing a new bearing, place a steel pipe
on the inner race surface, and t the bearing by
tapping it lightly with a hammer.
Figure 7. Bearing Puller
Note:Absolutely do not apply pressure to outer race
of the bearing during insertion.

OPX300K2 2/18
12
Maintenance
2. Replacement of Rotary Rectier Parts:
a. Rotary rectier parts are all located at the rear
of Exciter rotor. For parts replacement, remove
the bearing shield.
b. To test the rotating rectier diodes, disconnect
the lead to the diode element and measure the
resistance between the anode and cathode on
each diode (see Figure 8).
Caution: Do not overheat the diodes. If the resistance
value of the diode in the forward direction is low and
the reverse direction resistance value shows innity,
it is good. If this is not the case, the diode element is
defective and must be replaced. The diode elements
can be damaged if overtightened.
c. “J” type diode elements are fastened to the J(+)
side of the rotating rectier assembly, and “K”
type diode elements to the K(-) side.
Figure 8. Testing Diode Elements
d. The Diode Torque Specications for all 300
series models is 5 mm = 48 in. lb.
e. In order to test whether the rotating rectier
assembly surge absorber elements are good or
not, rst disconnect all lead wires as described
in PARTS REPLACEMENT METHOD, Point 2,
(above) and measure the resistance across surge
absorber elements with a tester.
• Good surge absorber elements have about 10-30 K
ohms, but if the resistance reading is near 0 ohms,
the surge absorber elements is defective and must be
replaced.
• Also, inspect outside of surge absorber and replace
if it is cracked.
• In addition, when installing surge absorber elements,
apply Loctite to the bolts.
3. Bearing Housing Replacement:
Inspect the O-Ring. If cracked, replace. Reassemble
carefully, aligning housing with bearing. Tighten
housing bolts to 2.5 kpm (18 ft/lbs.).

OPX300K2 2/18
13
4. Rotating Rectier Assembly Detailed Structure:
Figure 9. Rotating Rectier.
Maintenance – Automatic Voltage Regulator
1. Keep the AVR clean at all times. Make sure no dust or moisture accumulates
on the AVR.
2. Inspect periodically making sure that wiring connections are not loose.

OPX300K2 2/18
14
Generator Specications: Taiyo Winding Resistances
All ratings in Ohms @ 20° C
Model Number 1 Phase 3 Phase
MAIN PX-308K2 0.588 ohms 0.656 ohms
STATOR: PX-309K2 0.588 ohms 0.656 ohms
PX-310K2 0.527 ohms 0.436 ohms
PX-312K2 0.298 ohms 0.315 ohms
PX-316K2 0.234 ohms 0.198 ohms
PX-320K2 & PX-320C2 0.195 ohms 0.136 ohms
PX-325K2 0.115 ohms 0.0950 ohms
PX-332K2 & PX-332C2 0.094 ohms 0.0817 ohms
Model Number 1 Phase 3 Phase
MAIN PX-308K2 1.84 ohms 1.84 ohms
ROTOR: PX-309K2 1.84 ohms 1.84 ohms
PX-310K2 1.95 ohms 1.95 ohms
PX-312K2 2.10 ohms 2.10 ohms
PX-316K2 2.40 ohms 2.40 ohms
PX-320K2 & PX-320C2 2.77 ohms 2.77 ohms
PX-325K2 3.60 ohms 3.60 ohms
PX-332K2 & PX-332C2 3.91 ohms 3.91 ohms
Model Number 1 Phase 3 Phase
EXCITER PX-308K2 & PX-309K2 15.8 ohms 15.8 ohms
STATOR: PX-310K2 15.8 ohms 15.8 ohms
PX-312K2 15.8 ohms 15.8 ohms
PX-316K2 17.0 ohms 17.0 ohms
PX-320K2 & PX-320C2 17.0 ohms 17.0 ohms
PX-325K2 17.0 ohms 17.0 ohms
PX-332K2 & PX-332C2 19.2 ohms 19.2 ohms

OPX300K2 2/18
15
Model Number 1 Phase 3 Phase
EXCITER PX-308K2 & PX-309K2 0.510 ohms 0.510 ohms
ROTOR: PX-310K2 0.510 ohms 0.510 ohms
PX-312K2 0.510 ohms 0.510 ohms
PX-316K2 0.530 ohms 0.530 ohms
PX-320K2 & PX-320C2 0.530 ohms 0.530 ohms
PX-325K2 0.530 ohms 0.530 ohms
PX-332K2 & PX-332C2 0.580 ohms 0.580 ohms
Model Number 1 Phase 3 Phase
FULL LOAD PX-308K2 & PX-309K2
EXCITATION 50 Hz/ 220 volts 31.8 volts 23.0 volts
VOLTAGE:60 Hz/ 240 volts 37.5 volts 27.1 volts
PX-310K2
50 Hz/ 220 volts 36.4 volts 26.2 volts
60 Hz/ 240 volts 41.7 volts 28.9 volts
PX-312K2
50 Hz/ 220 volts 45.5 volts 32.8 volts
60 Hz/ 240 volts 50.0 volts 36.1 volts
PX-316K2
50 Hz/ 220 volts 54.5 volts 39.4 volts
60 Hz/ 240 volts 66.7 volts 48.1 volts
PX-320K2 & PX-320C2
50 Hz/ 220 volts 72.7 volts 52.5 volts
60 Hz/ 240 volts 83.3 volts 60.1 volts
PX-325K2
50 Hz/ 220 volts 90.9 volts 52.5 volts
60 Hz/ 240 volts 104.2 volts 60.1 volts
PX-332K2 & PX-332C2
50 Hz/ 220 volts 118.2 volts 68.2 volts
60 Hz/ 240 volts 137.5 volts 79.4 volts
AUXILIARY WINDING: PX-309K2 5.87 ohms 2.89 ohms
PX-310K2 6.31 ohms 2.45 ohms
PX-312K2 5.31 ohms 2.37 ohms
PX-316K2 4.41 ohms 1.58 ohms
PX-320K2 & PX-320C2 3.49 ohms 1.57 ohms
PX-325K2 3.29 ohms 1.67 ohms
PX-332K2 & PX-332C2 3.09 ohms 1.49 ohms
Generator Specications: Taiyo Winding Resistances
All ratings in Ohms @ 20° C

OPX300K2 2/18
16
Sensing Output Frequency 50 Hz 60 Hz
Voltage 100 Volt Class 100V (86.5V~110V~120V) 120V
200 Volt Class 200V (173V~220V~240V) 240V
Phase: Single Phase Single Phase
Power Input Voltage: 100V ~ 127V ~ 139V
Frequency: 50 Hz / 60 Hz
Phase: Single Phase Single Phase
Sensing Output Max. Voltage: 87% of Power Input Voltage (DC Voltage)
(F+) – (F-) Continuous Current: Maximum 3A Current
Current Maximum Forcing: 9A forcing 1 to 5 seconds at 25°C
Field Resistance: Minimum 15 Ohms
Voltage Adjust Range Minimum ±5% of Normal Voltage
Volt/ Hertz Characteristic 57 Hz in 60 Hz operation mode, 47 Hz in 50 Hz operation mode
Voltage Build-Up Self-Building Up at over 6V Power Input Voltage
Voltage Changeable Rate Maximum ±1.5%
Temperature Drift Within ±0.02%/ degree C
Operating Temperature -4°F (-20°C) to 140°F (60°C)
Storage Temperature -4°F (-20°C) to 158°F (70°C)
Outside Dimension 5.6" x 4.0" x 1.57" (140mm x 100mm x 40 mm)
Weight 1.4 lbs. (0.65 kgs)
Automatic Voltage Regulator: DST-100-2FAK

OPX300K2 2/18
17
Trouble Shooting
PROBLEM POSSIBLE CAUSE RECOMMENDATION(S)
Only a FEW VOLTS Loss of residual magnetism of the exiter eld • Flash eld.
of output
Disconnection or short circuit of windings • Check the insulation of all windings
and check the resistance value.
Defective AVR • Check the AVR.
Defective rotating rectier assembly • Replace diode elements.
Voltage is LOW Incorrect wiring (GEN, AVR) • Check the winding connection.
Low speed • Check the engine.
Overload • Reduce the load.
Defective AVR • Check the AVR.
Voltage DIPS Starting of big motor or spot welding machine • About 15% voltage dip is no problem.
when on load
Defective diode on rotating rectier • Change diode.
[F(+) – F(-) terminal voltage will show a
very high value when a diode is defective]
Voltage is HIGH Incorrect wiring (GEN, AVR) • Check the AVR.
Too high speed • Check the engine.
Defective AVR • Check the AVR.
Voltage FLUCTUATES Wiring leads are loose • Tighten leads.
Irregular speed of engine • Check the engine.
Poor AVR adjustment • Check the AVR.
External noise • Check the lter.
Abnormal SOUND Foundation uneven • Check ground level.
or VIBRATION
Poor mounting • Check the mounting section.
Misaligned coupling • Check the coupling section.
Defective bearing • Replace the bearing.

OPX300K2 2/18
18
No Description PX-308K2 PX-309K2 PX-310K2 PX-312K2 PX-316K2
1 Stator Assembly (1-Phase) WKC-00112-ST WKC-00112-ST WKC-00094-ST WKC-00095-ST WKC-00096-ST
Stator Assembly (3-Phase) WKC-00113-ST WKC-00113-ST WKC-00101-ST WKC-00102-ST WKC-00103-ST
2 Rotor Assembly WKC-00112-RT WKC-00112-RT WKC-00094-RT WKC-00095-RT WKC-00096-RT
3 Rotor Fan 3T301-254-4 3T301-593-2 3T301-255-4 3T301-255-4 3T301-255-4
4 Excitor Stator Assembly (1-Phase) WKC-00107-ST WKC-00107-ST WKC-00107-ST WKC-00107-ST WKC-00108-ST
5 RectierAssembly 3T201-084-3* 3T201-084-3* 3T201-084-3* 3T201-084-3* 3T201-084-3*
6 Bearing Shield 3T301-253-4 3T301-253-4 3T301-253-4 3T301-253-4 3T301-253-4
7 O-Ring 1AG72 1AG72 1AG72 1AG72 1AG72
8 Ball Bearing 6306ZZ 6306ZZ 6306ZZ 6306ZZ 6306ZZ
9 Ventilation Cover (M Type) 3T301-329 3T301-329 3T301-331 3T301-331 3T301-331
Ventilation Cover (NL Type) 3T301-330 3T301-330 3T301-332 3T301-332 3T301-332
10 Junction Box (M Type) 1 Phase 3T102-346 3T102-346 3T102-346 3T102-346 3T102-346
Junction Box (NL Type) 1 Phase 3T102-349 3T102-349 3T102-349 3T102-349 3T102-349
Junction Box (M Type) 3 Phase 3T102-350 3T102-350 3T102-350 3T102-350 3T102-350
Junction Box (NL Type) 3 Phase 3T102-352 3T102-352 3T102-352 3T102-352 3T102-352
11 Rubber Mount 33-40007 33-40007 33-40007 33-40007 33-40007
13 Automatic Voltage Regulator 22-42071 22-42071 22-42071 22-42071 22-42071
14 Circuit Breaker (Voltage Regulator) 22-42084** 22-42084** 22-42084** 22-42084** 22-42084**
15 Circuit Breaker (Engine) 22-42043 22-42043 22-42043 22-42043 22-42043
17 Generator Mounting Bracket (R) 3T303-278 R 3T303-278 R 3T303-372 R 3T303-372 R 3T302-857-1 R
Generator Mounting Bracket (L) 3T303-278 L 3T303-278 L 3T303-372 L 3T303-372 L 3T301-857-1 L
18 Surge Suppressor for 3T201-084 ENC471D-2DA ENC471D-2DA ENC471D-2DA ENC471D-2DA ENC471D-2DA
19 Diode Element SKN26/12*** SKN26/12*** SKN26/12*** SKN26/12*** SKN26/12***
Diode Element SKR26/12**** SKR26/12**** SKR26/12**** SKR26/12**** SKR26/12****
*replaces 3T201-084-2 **replaces 22-42077 ***replaces SIDO1-09 (74113) ****replaces ERD51-09 (74114)
PX308 to PX316K2 generators 3T102-344
PX-300K2 Series Parts List
updated 9-13-10

OPX300K2 2/18
19
No Description PX-320K2 PX-325K2 PX-332K2
1 Stator Assembly (1-Phase) WKC-00097-ST WKC-00098-ST WKC-00099-ST
Stator Assembly (3-Phase) WKC-00104-ST WKC-00105-ST WKC-00106-ST
2 Rotor Assembly WKC-00097-RT WKC-00098-RT WKC-00099-RT
3 Rotor Fan 3T301-255-4 3T301-255-4 3T301-553
4 Excitor Stator Assembly (1-Phase) WKC-00108-ST WKC-00108-ST WKC-00109-ST
5 RectierAssembly 3T201-084-3* 3T201-084-3* 3T201-084-3* *replaces 3T201-084
6 Bearing Shield 3T301-253-4 3T301-253-4 3T301-349-2
7 O-Ring 1AG72 1AG72 1BG90
8 Ball Bearing 6306ZZ 6306ZZ 6308ZZ
9 Ventilation Cover (M Type) 3T301-331 3T301-331 3T301-389
Ventilation Cover (NL Type) 3T301-332 3T301-389
10 Junction Box (M Type) 1 Phase 3T102-346 3T102-347 3T102-348
Junction Box (NL Type) 1 Phase 3T102-349 3T102-348
Junction Box (M Type) 3 Phase 3T102-350 3T102-350 3T102-351
Junction Box (NL Type) 3 Phase 3T102-352 3T102-351
11 Rubber Mount 33-40007 33-40007 33-40007
13 Automatic Voltage Regulator 22-42071 22-42071 22-42071
14 Circuit Breaker (Voltage Regulator) 22-42084** 22-42084** 22-42084** **replaces 22-42077
15 Circuit Breaker (Engine) 22-42043 22-42043 22-42043
17 Generator Mounting Bracket (R) 3T302-857-1 R 3T302-857-1 R 23-65413
Generator Mounting Bracket (L) 3T302-857-1 L 3T302-857-1 L 23-65413
Generator Mtg. Bracket (R&L) 23-61201 M944 & M30CW
18 Surge Suppressor for 3T201-084 ENC471D-2DA ENC471D-2DA ENC471D-2DA
19 Diode Element SKN26/12*** SKN26/12*** SKN26/12*** ***replaces SID01-09 (74113)
Diode Element SKR26/12**** SKR26/12**** SKR26/12**** ****replaces ERD51-09 (74114)
PX320 to PX325K2 generators
PX332K2 generators 3T102-344
}M984 & M33C
PX-300K2 Series Parts List
updated 9-13-10

OPX300K2 2/18
20
page corrected 5/24/12
No Description PX-320C2
1 Stator Assembly WKC-00104-5-ST
2 Rotor Assembly WKC-00104-5-RT
3 Excitor Stator Assembly WKC-00108-ST
4 RectierAssembly  3T201-084-3* *replaces 3T201-084
5 Bearing Shield 3T301-253-4
6 O-Ring 1AG72
7 Ball Bearing 6306ZZ
8 Ventilation Cover (M Type) 3T302-896
9 Junction Box (M Type) 3T303-290-2
10 Junction Box Top 4T301-108
11 Junction Box Side (2 ea.) 4T301-109
12 Rubber Mount 33-40007
13 Automatic Voltage Regulator 22-42071
14 Circuit Breaker (Voltage Regulator) 22-42084** **replaces 22-42077
15 Circuit Breaker (Engine) 22-42043
16 Spacer 4T301-181 (4 ea.)
17 Generator Mounting Bracket (R) 3T302-857-1 R
Generator Mounting Bracket (L) 3T302-857-1 L
18 Surge Suppressor for 3T201-084 ENC471D-2DA
19 Diode Element SKN26/12*** (3 ea.) ***replaces SID01-09 (74113)
Diode Element SKR26/12**** (3 ea.) ****replaces ERD51-09 (74114)
20 Rotor Fan & Coupling 3T301-255-4
23 Drip Proof Cover 4T302-897
24 Foot for Drip Proof Cover (4 ea.) 4T302-898
25 Terminal Strip (Auxiliary) TE-K22-4
26 Terminal Strip (Output) UK60-3J
PX320C2 generator PX320C
PX-320C2 Parts List