Miller DYNASTY DX User manual

TM-357A June 1999
Eff. w/Serial Number KH384382
Processes
Description
TIG (GTAW) Welding
Stick (SMAW) Welding
Arc Welding Power Source
Dynasty DX
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TABLE OF CONTENTS
SECTION 1 – SAFETY PRECAUTIONS FOR SERVICING 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-1. Symbol Usage 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-2. Servicing Hazards 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1-3. EMF Information 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 2 – INSTALLATION 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-1. Specifications 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-2. Duty Cycle and Overheating 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-3. Volt-Ampere Curves 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-4. Selecting a Location 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-5. Weld Output Terminals and Selecting Cable Sizes 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-6. Remote 14 Receptacle Information 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-7. 115 Volts AC Duplex Receptacle (Optional), Power Switch Location, and Circuit
Breaker CB1 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-8. Electrical Service Guide 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-9. Connecting Input Power 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 3 – OPERATION 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-1. Controls 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-2. AC/Balance Control 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-3. Meter Function 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-4. Output Switch Settings 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-5. Sequence Control 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-6. Lift-Arc and HF TIG Start Procedures 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 4 – THEORY OF OPERATION 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 5 – PRE-POWER CHECKLIST 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-1. Checking Unit Before Applying Power 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-2. Input Rectifier SR1 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-3. Tank Capacitor C1 and Input Capacitors C3, C4 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-4. Output Diodes D1, D2 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-5. IGBT Modules PM1, PM2, PM3, PM4 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-6. Diodes D1, D2, D3, D4 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5-7. Contactors W1, W2 (230/460 V Models Only) 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 6 – TROUBLESHOOTING 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-1. Troubleshooting Table 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-2. Troubleshooting Circuit Diagram 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-3. Waveforms for Sections 6-2 24. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-4. Control Board PC1 Testing Information (Use with Section 6-5) 26. . . . . . . . . . . . . . . . . . . . . . . . .
6-5. Control Board PC1 Test Point Values 27. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-6. Display Board PC3 Testing Information (Use with Section 6-7) 29. . . . . . . . . . . . . . . . . . . . . . . . .
6-7. Display Board PC3 Test Point Values 30. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-8. Interconnecting Board PC2 Testing Information 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-9. High-Frequency Board PC7 Testing Information (Use with Section 6-10) 32. . . . . . . . . . . . . . . .
6-10.High-Frequency Board PC7 Test Point Values 33. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-11.Clamp Board PC8 Testing Information (Use with Section 6-12) 34. . . . . . . . . . . . . . . . . . . . . . . .
6-12.Clamp Board PC8 Test Point Values 35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-13.Secondary IGBT Board PC6 Testing Information (Use with Section 6-14) 36. . . . . . . . . . . . . . . .
6-14.Secondary IGBT Board PC6 Test Point Values With Contactor Off 37. . . . . . . . . . . . . . . . . . . . .
SECTION 7 – MAINTENANCE 38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7-2. Blowing Out Inside of Unit 38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7-3. Overload Protection 38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7-4. Voltmeter/Ammeter Help Displays 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7-5. Measuring Input Capacitor Voltage 40. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 8 – HIGH FREQUENCY 41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8-1. Welding Processes Requiring High Frequency 41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8-2. Incorrect Installation 41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8-3. Correct Installation 42. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 9 – ELECTRICAL DIAGRAMS 43. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 10 – PARTS LIST For KH384382 Thru KJ150395 68. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 11 – PARTS LIST For KJ150396 And Following 74. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM-357-A

TM-357 Page 1Dynasty DX
SECTION 1 –SAFETY PRECAUTIONS FOR SERVICING
1-1. Symbol Usage
OM-357D 4/98, safety_stm 5/97
Means Warning! Watch Out! There are possible hazards
with this procedure! The possible hazards are shown in
the adjoining symbols.
YMarks a special safety message.
.Means “Note”; not safety related.
This group of symbols means Warning! Watch Out! possible
ELECTRIC SHOCK, MOVING PARTS, and HOT PARTS hazards.
Consultsymbols and related instructions below for necessary actions
to avoid the hazards.
1-2. Servicing Hazards
YThe symbols shown below are used throughout this manual to
call attention to and identify possible hazards. When you see
the symbol, watch out, and follow the related instructions to
avoid the hazard.
YOnly qualified persons should service, test, maintain, and re-
pair this unit.
YDuring servicing, keep everybody, especially children, away.
ELECTRIC SHOCK can kill.
DDo not touch live electrical parts.
DTurn Off welding power source and wire feeder
and disconnect and lockout input power using
linedisconnect switch, circuit breakers, or by removing plug from re-
ceptacle,or stop engine before servicing unless the procedure spe-
cifically requires an energized unit.
DInsulateyourself from ground by standing or working on dry insulat-
ing mats big enough to prevent contact with the ground.
DDo not leave live unit unattended.
DIf this procedure requires an energized unit, have only personnel
familiarwith and following standard safety practices do the job.
DWhentesting a live unit, use the one-hand method. Do not put both
hands inside unit. Keep one hand free.
DDisconnect input power conductors from deenergized supply line
BEFORE moving a welding power source.
SIGNIFICANT DC VOLTAGE exists after removal of
input power on inverters.
DTurn Off inverter, disconnect input power, and discharge input
capacitorsaccording to instructions in Maintenance Section before
touchingany parts.
STATIC (ESD) can damage PC boards.
DPut on grounded wrist strap BEFORE handling
boards or parts.
DUse proper static-proof bags and boxes to
store, move, or ship PC boards.
FIRE OR EXPLOSION hazard.
DDo not place unit on, over, or near combustible
surfaces.
DDo not service unit near flammables.
FLYING METAL can injure eyes.
DWear safety glasses with side shields or face
shield during servicing.
DBe careful not to short metal tools, parts, or
wires together during testing and servicing.
HOT PARTS can cause severe burns.
DDo not touch hot parts bare handed.
DAllowcooling period before working on welding
gun or torch.
EXPLODING PARTS can cause injury.
DFailedparts can explode or cause other parts to
explodewhen power is applied to inverters.
DAlways wear a face shield and long sleeves
when servicing inverters.
SHOCK HAZARD from testing.
DTurn Off welding power source and wire feeder
or stop engine before making or changing me-
ter lead connections.
DUse at least one meter lead that has a self-
retainingspring clip such as an alligator clip.
DRead instructions for test equipment.
FALLING UNIT can cause injury.
DUse lifting eye to lift unit only, NOT running
gear, gas cylinders, or any other accessories.
DUse equipment of adequate capacity to lift and
supportunit.
DIf using lift forks to move unit, be sure forks are
long enough to extend beyond opposite side of
unit.
MOVING PARTS can cause injury.
DKeep away from moving parts such as fans.
DKeep all doors, panels, covers, and guards
closed and securely in place.

TM-357 Page 2 Dynasty DX
MOVING PARTS can cause injury.
DKeep away from moving parts.
DKeep away from pinch points such as drive
rolls.
MAGNETIC FIELDS can affect pacemak-
ers.
DPacemakerwearers keep away from servicing
areas until consulting your doctor.
OVERUSE can cause OVER-
HEATING.
DAllow cooling period; follow rated duty cycle.
DReduce current or reduce duty cycle before
startingto weld again.
DDo not block or filter airflow to unit.
H.F. RADIATION can cause interference.
DHigh-frequency(H.F.) can interfere with radio
navigation, safety services, computers, and
communicationsequipment.
DHave only qualified persons familiar with
electronicequipment install, test, and service
H.F. producing units.
DThe user is responsible for having a qualified electrician prompt-
ly correct any interference problem resulting from the installa-
tion.
DIf notified by the FCC about interference, stop using the
equipmentat once.
DHave the installation regularly checked and maintained.
DKeephigh-frequency source doors and panels tightly shut, keep
spark gaps at correct setting, and use grounding and shielding to
minimizethe possibility of interference.
READ INSTRUCTIONS.
DUse MILLER Testing Booklet (Part No. 150
853) when servicing this unit.
DConsultthe Owner’s Manual for welding safety
precautions.
DUse only genuine MILLER replacement parts.
1-3. EMF Information
Considerations About Welding And The Effects Of Low Frequency
Electric And Magnetic Fields
Weldingcurrent, as it flows through welding cables, will cause electro-
magnetic fields. There has been and still is some concern about such
fields. However, after examining more than 500 studies spanning 17
years of research, a special blue ribbon committee of the National
Research Council concluded that: “The body of evidence, in the
committee’s judgment, has not demonstrated that exposure to power-
frequency electric and magnetic fields is a human-health hazard.”
However, studies are still going forth and evidence continues to be
examined.Until the final conclusions of the research are reached, you
may wish to minimize your exposure to electromagnetic fields when
weldingor cutting.
To reduce magnetic fields in the workplace, use the following
procedures:
1. Keep cables close together by twisting or taping them.
2. Arrange cables to one side and away from the operator.
3. Do not coil or drape cables around your body.
4. Keep welding power source and cables as far away from opera-
tor as practical.
5. Connect work clamp to workpiece as close to the weld as possi-
ble.
About Pacemakers:
Pacemakerwearers consult your doctor first. If cleared by your doctor,
thenfollowing the above procedures is recommended.

TM-357 Page 3Dynasty DX
SECTION 2 –INSTALLATION
2-1. Specifications
Amperage Maximum Amperes Input at Rated Load Output 60 Hz
Input Power Rated Welding Output
Amperage
Range Open-Circuit
Voltage DC 230 V 460 V KVA KW
250 A @ 30 Volts AC, 40%
Duty Cycle 26.3 *.27 17.9 *.15 14.2 *.09 10.5 *.04
Three Phase 200 A @ 28 Volts DC, 40%
Duty Cycle
5–300 90 20.5
*.27 13.4 *.15 8.4 *.09 7.6 *.04
250 A @ 30 Volts AC, 40%
Duty Cycle 62.6
*.33 32.2 *.18 14.8 *.10 10.4 *.07
Single Phase 200 A @ 28 Volts DC, 40%
Duty Cycle
5–300 90 44
*.33 25.8 *.18 11.9 *.1 8.1 *.07
*While idling
2-2. Duty Cycle and Overheating
4 Minutes Welding 6 Minutes Resting
Duty Cycle is percentage of 10 min-
utes that unit can weld at rated load
withoutoverheating.
If unit overheats, output stops, a
Help message is displayed (see
Section7-4), and cooling fan runs.
Wait fifteen minutes for unit to cool.
Reduce amperage or voltage, or
duty cycle before welding.
YExceeding duty cycle can
damage unit and void
warranty.
250 A @ 40% Duty Cycle For AC
Overheating 0
15
A or V
OR
Reduce Duty Cycle
Minutes
sduty1 5/95 / SA-185 794
200 A @ 40% Duty Cycle For DC

TM-357 Page 4 Dynasty DX
2-3. Volt-Ampere Curves
SA-185 793 / SA-186 294
Volt-amperecurves show minimum
and maximum voltage and amper-
age output capabilities of unit.
Curves of other settings fall be-
tween curves shown.

TM-357 Page 5Dynasty DX
2-4. Selecting a Location
loc_2 3/96 - ST-801 708-A
1 LiftingHandles
Use handles to lift unit.
2 Hand Cart
Use cart or similar device to move
unit.
3 Rating Label
Use rating label to determine input
power needs.
4 Line Disconnect Device
Locate unit near correct input
power supply.
YSpecial installation may be
required where gasoline or
volatileliquids are present –
see NEC Article 511 or CEC
Section20.
24 in
(610 mm)
17 in
(432 mm)
12-1/2 in
(318 mm)
Movement 1
2
YDo not move or operate unit
where it could tip.
Location
4
3
Dimensions And Weight
18 in
(460 mm)
18 in
(460 mm)
90 lb (40.7 kg)
1

TM-357 Page 6 Dynasty DX
2-5. Weld Output Terminals and Selecting Cable Sizes
Total Cable (Copper) Length In Weld Circuit Not Exceeding
100 ft (30 m) Or Less 150 ft
(45 m) 200 ft (60 m) 250 ft (70 m) 300 ft (90 m) 350 ft (105 m) 400 ft (120 m)
Weld Output
Terminals Welding Amperes
10 –60%
Duty
Cycle
60 –100%
Duty Cycle 10 –100% Duty Cycle
100 4 4 4 3 2 1 1/0 1/0
150 3 3 2 1 1/0 2/0 3/0 3/0
200 3 2 1 1/0 2/0 3/0 4/0 4/0
250 2 1 1/0 2/0 3/0 4/0 2-2/0 2-2/0
300 1 1/0 2/0 3/0 4/0 2-2/0 2-3/0 2-3/0
Work Electrode 350 1/0 2/0 3/0 4/0 2-2/0 2-3/0 2-3/0 2-4/0
*Weld cable size (AWG) is based on either a 4 volts or less drop or a current density of at least 300 circular mils per ampere. Contact your
distributor for the mm2equivalent weld cable sizes.
NOTE: For proper installation of gas hose, the use of a quick connect torch (such as Weldcraft QWP-17 or QWP-20), is recommened.S-0007E
2-6. Remote 14 Receptacle Information
Socket* Socket Information
ST-801 708-A
24 VOLTS DC
AContactorcontrol, 24 volts dc.
AJ
BKI
CLNH
24 VOLTS DC
BContact closure to A completes 24 volts dc
contactor control circuit, and enables output.
DMG
EFCOutput to remote control; 0 to +10 volts dc output
to remote control.
REMOTE DRemotecontrol circuit common.
OUTPUT
CONTROL E0 to +10 volts dc input command signal from
remote control.
MNot used.
A/V FCurrent feedback; +1 volt dc per 100 amperes. A/V
AMPERAGE
VOLTAGE HVoltagefeedback; +1 volt dc per 10 output
receptacle volts.
GND K Chassis common.
*The remaining sockets are not used.

TM-357 Page 7Dynasty DX
2-7. 115 Volts AC Duplex Receptacle (Optional), Power Switch Location, and Circuit
Breaker CB1
ST-801 866-A
1 115 V 10 A AC Receptacle
2 Circuit Breaker CB1
CB1 protects the 115 volts ac du-
plex receptacle from overload.
Press button to reset breaker.
3 Power On/Off Switch
1
32
2-8. Electrical Service Guide
Actual input voltage cannot exceed ±15% of indicated required input voltage. If
actual input voltage is outside of this range, no output is available.
NOTE
Three-Phase Single-Phase
Input Voltage 230 460 230 460
AC 26.5 17.9 62.6 32.2
Input Amperes At Rated Output DC 20.5 13.4 44 25.8
Max Recommended Standard Fuse Or Circuit Breaker
Rating In Amperes 50 25 100 50
Min Input Conductor Size In AWG/Kcmil 10 14 8 10
Max Recommended Input Conductor Length In Feet
(Meters) 104 (32) 165 (50) 90 (27) 241 (74)
Min Grounding Conductor Size In AWG/Kcmil 10 14 8 10
Reference: 1996 National Electrical Code (NEC). S-0092J

TM-357 Page 8 Dynasty DX
2-9. Connecting Input Power
Check input voltage available at
site.
1 InputAnd Grounding
Conductors
2 Line Disconnect Device
See Section 2-8.
For single-phase operation:
3 Black And White Input
Conductor
4 Red Input Conductor
5 Insulation Sleeving
6 Electrical Tape
Insulate and isolate red conductor
as shown.
YAlways connect green wire
to supply grounding termi-
nal, never to a line terminal.
For three-phase operation:
Connectblack, white, and red wires
(L1, L2, L3) to line terminals.
YAlways connect green wire
to supply grounding termi-
nal, never to a line terminal.
Tools Needed:
L1
22
1
1
1
3
1
65
4
L2
L3 L1
L2
YAlways connect grounding
conductor first.
1
3
= GND/PE
Green Green
Green
3/8 in
3/8 in
input_2 3/96 - ST-801 709-A

TM-357 Page 9Dynasty DX
SECTION 3 –OPERATION
3-1. Controls
Ref. ST-187 198
1 AC Frequency Control
Range is 20 to 250 hertz. For most applica-
tions, increasing frequency improves arc
stability.
2 Balance/DIGControl
Control functions as a balance control for
GTAW (TIG) process, and in the DIG mode
for SMAW (STICK) process, depending on
positionof Process control.
Balance Mode:
See Section 3-2.
DIG Mode:
When set lower, short-circuit amperage at
low arc voltage is the same as normal
weldingamperage.
When set higher, short-circuit amperage is
increasedat low arc voltage to help with arc
starting and making overhead or vertical
welds, as well as to reduce sticking while
welding.
3 Voltmeter(see Section 3-3)
Voltmeterdisplays voltage (to the nearest 0.1
V) at the weld output terminals, but not nec-
essarily the welding arc due to cable resis-
tance, poor connections, etc.
4 Ammeter (see Section 3-3)
Use ammeter to preset amperage. Meter dis-
plays weld amperage output of unit when
welding.
5 AmperageAdjustment Control
Turn control clockwise to increase amperage
from 5 to 300 amps.
6 Output Control Switch
See Section 3-4.
7 Amperage Control Switch
For front panel control, place switch in Panel
position.
For remote control, make connections to
remote 14 receptacle, and place switch in
Remote14 position.
8 Trigger Hold
To start weld, press and release gun trigger
within three seconds after an arc has been
struck. To end weld, press and release gun
trigger. If gun trigger is not released within 3
seconds, unit switches to standard trigger
controloperation.
9 Process Control
Use control to select either of the GTAW
(TIG) welding process and polarity, or the
SMAW (Stick) welding process.
Selecting any GTAW (TIG) position enables
the gas valve, which is disabled when SMAW
(Stick) position is selected.
10 Sequence Control
See Section 3-5.
11 Start A (Amperage) Control
Use control to select a starting amperage
that is different from the weld amperage.
12 Start t (Amperage Time) Control
Use control to select length of time in
seconds that amperage remains at start
amperage before changing to weld
amperage.
For example, to select start amperage of 300
A for 3 seconds and weld amperage of 200
A: Set Start A amperage control to 300 A, set
Start t time control to 3 seconds, and set front
panelor remote amperage control to 200 A.
13 Crater Control
Control sets length of time in seconds to
taper weld output from weld amperage
settingto 0 A .
14 Postflow Control
Control sets length of time in seconds gas
flows after the welding stops.
12 34 5
8
6
7
91411 10
12
13

TM-357 Page 10 Dynasty DX
3-2. AC/Balance Control
BalanceControl:
Control changes the ac output
square wave.
Adjust setting for deeper
penetration or more cleaning
action.
ÈÈÈ
ÈÈÈ
ÈÈÈ
ÈÈÈ
ÈÈ
ÈÈ
ÈÈÈÈ
ÈÈÈÈ
È
È
100
0
Max Penetration
At 20 Hz
Max Penetration
At 250 Hz
Max Cleaning At
All Hz
1% Electrode
Positive
99% Electrode
Negative
10% Electrode
Positive
90% Electrode
Negative
50% Electrode
Positive
50% Electrode
Negative
ÈÈÈ
ÈÈÈ
È
È
ÈÈÈ
ÈÈÈ
È
È
ÈÈÈ
ÈÈÈ
È
È
ÈÈÈ
ÈÈÈ
ÈÈ
ÈÈ
ÈÈÈ
ÈÈÈ
100
Balance Control Waveform Examples
ÈÈ
ÈÈ
ÈÈ
ÈÈ
ÈÈ
ÈÈ
ÈÈ
ÈÈ
3-3. Meter Function
Mode Meter Reading At Idle Meter Reading While Welding
On
VA
Actual Volts (OCV) Preset Amps
80.0 85 Actual Volts Actual Amps
VA
24.5 85
Lift On
Actual Volts Preset Amps
VA
7.0 85 Actual Volts Actual Amps
VA
10.3 85
HF Remote
Blank Preset Amps
VA
85 Actual Volts Actual Amps
VA
10.3 85
Lift Remote
Blank Preset Amps
VA
85 Actual Volts Actual Amps
VA
10.3 85
Remote
Blank Preset Amps
VA
85 Actual Volts Actual Amps
VA
24.5 85
3-4. Output Switch Settings
Output Switch Setting Process Output On/Off Control
On SMAW (Stick) Electrode Hot
Lift On GTAW (TIG) With Lift-Arc Start –See Section
3-6 Electrode Hot
HF Remote GTAW (TIG) With HF Start –See Section 3-6 At Remote 14
Lift Remote GTAW (TIG) At Remote 14
Remote SMAW (Stick) At Remote 14

TM-357 Page 11Dynasty DX
3-5. Sequence Control
For The Following Processes
Control Position Allows These Controls To Be Functional For The Following Processes
SMAW (Stick)/GTAW (TIG)
Stick
Off Postflow t –0-50 Seconds TIG
Start
Start t (Time) –0-15 Seconds
Start A (Amperage0 –0-300 Amps Stick/TIG
Start Postflow –0-50 Seconds TIG
Crater Crater t –0-15 Seconds
Postflow t –0-50 Seconds TIG
Start/Crater Start t (Time) –0-15 Seconds
Start A (Amperage) –0-300 Amps
Crater t –0-15 Seconds
Postflow –0-50 Seconds TIG
3-6. Lift-Arc and HF TIG Start Procedures
With Output Switch in Lift On
position,start arc as follows:
1 TIG Electrode
2 Workpiece
Touch tungsten electrode to work-
piece at weld start point, hold
electrode to workpiece for 1-2
seconds, and slowly lift electrode.
An arc will form when electrode is
lifted.
Normal open-circuit voltage is not
present before tungsten electrode
touches workpiece; only a low
sensingvoltage is present between
electrode and workpiece. The
solid-state output contactor does
not energize until after electrode is
touching workpiece. This allows
electrodeto touch workpiece with-
out overheating, sticking, or getting
contaminated.
With Output Switch in HF Remote
position,start arc as follows:
High frequency turns on to help
start arc when contactor is ener-
gized. High frequency turns off
when arc is started, and turns on
whenever arc is broken to help
restart arc.
1
1 –2
Seconds
“Touch”
Do NOT Strike Like A Match!
2
Ref. ST-156 279

TM-357 Page 12 Dynasty DX
1 Power Switch S1
Provides on/off control of welding
power source.
2 Input Rectifier SR1
Changes the ac line input power to
full-wave rectified dc.
3 Control Transformer T2
Supplies power to control board
PC1, interconnecting board PC2,
Remote 14 receptacle RC1, and
HF board PC7.
4 Circuit Breaker CB1
Provides overload protection for
optional115 volt ac receptacle.
5 Circuit Breaker CB2
Prior to Serial No. KJ037293, pro-
vides overload protection for 24
volts ac portion of Remote 14
receptacleRC1.
6 115 Volt AC Receptacle
Connects auxiliary equipment to
weldingpower source.
7 Remote 14 Receptacle RC1
Connects remote amperage or
voltage,and contactor controls.
8 Control Board PC1
Controls weld output by changing
gatepulses (frequency of pulses) to
IGBT power modules PM1 and
PM2 after comparing current feed-
back to reference level set by R5 on
PC3.
9 460 V Input Contactor W1
Connectsthe 220 volts ac second-
ary voltage from T2 to interconnec-
ting board PC2 to balance voltage
on input capacitors C3 and C4.
10 230 V Auto-Link Contactor
W2
Provides automatic linking for dif-
ferentinput voltages. W2 sets pow-
er circuit for correct input voltage.
W2A sets T2 primary.
11 Fan Motor FM
Providescooling of internal compo-
nents.
12 Display Board PC3 (See
Section 3-1)
Consists of voltmeter V, ammeter
A, Amperage Adjustment control
R5, Amperage Control switch S1,
AC Frequency control R81, Bal-
ance/Dig control R82, Start Time
control R83, Start Amperage con-
trol R85, Crater Time control R84,
Postflow Time control R86, Se-
quenceControl switch S4, Process
Select switch S3, Output Select
switch S2, and Trigger Hold switch
S5.
SECTION 4 –THEORY OF OPERATION
Control
Transformer T2
Power
Switch
S1
Voltmeter
V
Display Board PC3
Three-Phase
Line Input
Power
9
12
3
8
4
115 Volts AC
Receptacle
6
5
7
Circuit
Breaker
CB1
Circuit
Breaker
CB2
Remote 14
Receptacle
RC1
Ammeter
A
10
Fan Motor
FM
11
460 V Input
Contactor W1 230 V
Auto-Link
Contactor W2
Control Board PC1
SCR/
Auto-Link
Contacts
10
15
Interconnecting
13
Input
Capacitors
C3, C4
16
IGBT Board
16
IGBT Board
Module PM1
17 17
W1
Gating
Signals Gating Signals
115
VAC 24 VAC
18
VAC
Center-
Tapped 220
VAC
220
VAC
IGBT Power Module PM2 IGBT Power
14
Inductors
L1, L3, L4
12
Board PC2
W2, W2A
PC4 PC5
Integrated
Rectifier SR1
♦
Ribbon
Cable
AC
Frequency
ControlR81 Balance/Dig
Control R82
Amperage
Adjustment
Control R5
Start Time
Control
R83 Crater Time
Control R84 Process
Control
Switch S3
Output
Control
Switch S2
Amperage
Control
Switch S1
Sequence
Control
Switch S4
Start
Amperage
Control R85
Postflow
Control R86 Trigger
Hold Switch
S5
♦

TM-357 Page 13Dynasty DX
13 Input Capacitors C3, C4
Filter the dc output voltage of SR1.
14 Inductors L1, L3, L4
L1 limits peak current in SR1, C3,
and C4. L3 and L4 limit voltage and
current in IGBT’s during turn-on
and turn-off.
15 Interconnecting Board PC2
Provides electrical connections for
SR1, T1, C3, C4, L1, L3, L4, and
IGBT’s. Precharge and bleeder
resistors are mounted on PC2.
16 IGBT Boards PC4, PC5
Provide interconnection of gate
pulses from PC1 to PM1 and PM2.
17 IGBT Power Modules PM1,
PM2
Use very fast on/off switching ac-
tiontoeffectively turn the dc into ac.
18 Current Transformer CT1
Provides current feedback to PC1
from the primary of T1 for control
circuit timing and to limit primary
current.
19 Main Transformer T1
Energizes by on/off switching ac-
tionof PM1 and PM2, and supplies
power to weld output circuit.
20 Output Diodes D1, D2
Rectify output of T1.
21 Stabilizer Z1
Smooths out welding current.
22 Hall Device HD1
Providesweld or secondary current
feedbacksignal to PC1.
23 IGBT Switching Modules PM3
And PM4
Use very fast on/off switching ac-
tiontoeffectively turn the dc into ac
output;also control AC balance.
24 Clamp Board PC8
Clamps voltage spikes created by
AC switching to protect switching
IGBT’s PM3 and PM4.
25 HF Board PC7
Creates the high-frequency (HF)
energy to start the arc.
26 HF Coupling Coil T3
CouplesHF energy created on PC7
to weld output circuit.
27 Electrode And Work Weld
Output Receptacles
Provide weld output and allow
changingof output polarity.
3φPower
AC Or DC Control Circuits
Weld Current Circuit
Optional
♦
18
Main
Transformer
T1
19 20
Hall
Device
HD1
22
Electrode
Weld Output
Receptacle
27
Work
Weld Output
Receptacle
27
Electrode
Voltage Feedback
Current
Stabilizer
Z1
21
Work
Output
Diodes
D1, D2
Voltage Feedback
T1 Primary
Current
Feedback
Current
Transformer
CT1
IGBT Switching Modules
PM3, PM4
Feedback
Clamp Board
PC8
24
Coupling Coil
T3 HF Board
PC7
23
2526 HF

TM-357 Page 14 Dynasty DX
SECTION 5 –PRE-POWER CHECKLIST
5-1. Checking Unit Before Applying Power
.See Section 6-2 for test points and values and Section
10 for parts location.
YDischarge input capacitors according to Section 7-5 and be sure voltage is near zero before touching any parts.
YBefore troubleshooting or applying power to unit, complete following checks to avoid causing further damage.
YAlthoughcontrol board PC1 and hall device HD1 are briefly checked in this procedure, more complete tests may be needed later for
these parts. This check is simply to get a basic okay to power up unit.
5-2. Input Rectifier SR1
ST-801 550 / Ref. SD-183 484
YRead and follow safety
information in Section 5-1
before proceeding.
.Resistance values are based
on in-circuit measurements.
1 Visually inspect SR1 for
damage.
2 Check 6 diodes (diode test).
Check from each ac terminal
to the positive (+) terminal and
from each ac terminal to the
negative (–) terminal.
3 Check precharge SCR (ohms
position). Connect negative
lead to SCR (–) terminal and
positive lead to positive (+)
terminal. Resistance should
be 200 ohms ±10%. Connect
a jumper between positive (+)
and gate terminals.
Resistance should be
approximately 35 ohms.
4 If results are in doubt, use an
IGBT tester (MILLER Part No.
043 553) to test the SCR
portion of SR1 as follows:
A. Disconnect plug PLG13
fromreceptacle RC1 on in-
terconnectingboard PC2.
B. Connectred clip to positive
(+) terminal.
C. Connect black clip to SCR
(–) terminal.
D. Connectyellow clip to gate
terminal.
5 If SR1 is defective, check the
three poles of power switch
S1 (switch off = OL, switch on
= 0 ohms).
Input Rectifier SR1
Gate
SCR (–)
AC (L3)
AC (L2)
AC (L1)
Positive (+)
Negative (–)
Power Switch S1
–
+
G
R2
T
S
R

TM-357 Page 15Dynasty DX
5-3. Tank Capacitor C1 and Input Capacitors C3, C4
ST-801 550
YRead and follow safety
information in Section 5-1
before proceeding.
.This is not a conclusive test.
For best results use a capacitor
tester to check capacitance.
.If either C3 or C4 is shorted, re-
move interconnecting board
PC2 and check IGBT’s PM1
and PM2.
1 Check C1, C3, and C4 for a
short (ohms position).
Tank Capacitor C1
Input Capacitors C3, C4
5-4. Output Diodes D1, D2
Ref. SD-183 484 / ST-802 037
YRead and follow safety
information in Section 5-1
before proceeding.
1 Test diodes individually
according to the Diode Testing
Procedure in the MILLER
Testing Booklet (Part No. 150
853).
Diodes D1, D2
Weld Output
Receptacles

TM-357 Page 16 Dynasty DX
5-5. IGBT Modules PM1, PM2, PM3, PM4
Best Test For PM1 And PM2 (Use MILLER
IGBT tester #043553)
YRead and follow safety information in
Section 5-1 before proceeding.
.It is not necessary to remove interconnect-
ing board PC2 to test the IGBT’s unless in-
put capacitor C3 or C4 is shorted.
1 Disconnect gate lead plug PLG5 from
receptacle RC5 on control board PC1.
Test PM1 as follows:
2 Connect red tester lead to C1, black tester
lead to E1, and yellow tester lead to gate
(PLG5–pin 10). Next, connect red lead to
C2, black lead to E2, and yellow tester
lead to gate (PLG5–pin 7).
Test PM2 as follows:
3 Connect red tester lead to C1, black lead
to E1, and yellow lead to gate (PLG5–pin
6). Next, connect red lead to C2, black
lead to E2, and yellow lead to gate
(PLG5–pin 9).
Connect PLG5 to RC5.
If IGBT’s 1 or 2 are defective, check D1, D2, D3,
and D4 on PC2 (see Section 5-6). Also check
W1 and W2 in 230/460 volt models (see Section
5-7).
Proceed to top of next page to test PM3 and
PM4.
Alternate Test For PM1 And PM2 (Use stan-
dard digital meter set to ohms position)
YRead and follow safety information in
Section 5-1 before
proceeding.
.It is not necessary to remove interconnect-
ing board PC2 to test the IGBT’s unless in-
put capacitor C3 or C4 is shorted.
1 Disconnect gate lead plug PLG5 from
receptacle RC5 on control board PC1.
2 For PM1 and PM2, measure between C1
and E1, and then between C2 and E2 (a
high resistance means device is okay,
zero ohms means device is shorted)
3 For PM1, check for 100K ohms resistance
(+/–10%) between the following:
E1 and PLG5–pin 10
E2 and PLG5–pin 7
4 For PM2, check for 100K ohms resistance
(+/–10%) between the following:
E1 and PLG5–pin 6
E2 and PLG5–pin 9
Connect PLG5 to–RC5.
If IGBT’s 1 or 2 are defective, check D1, D2, D3,
and D4 on PC2 (see Section 5-6). Also check
W1 and W2 in 230/460 volt models (see Section
5-7).
Proceed to bottom of next page to test PM3 and
PM4.
ControlBoard PC1
Receptacle
RC5
Terminal
C1
Terminal
E2
Terminal
C2/E1
IGBT Module PM1 Or PM2
Rear Of Unit
ST-802 275 / Ref. SD-183 484 / SA-188 731-A
6
12
PLG5
Tab Lock
Bottom View
15
10 6

TM-357 Page 17Dynasty DX
Best Test For PM3 And PM4 (Use
MILLER IGBT tester #043553)
(Continued)
YRead and follow safety
information in Section 5-1
before proceeding.
1 Visually inspect PM3 and
PM4 for damage.
2 Disconnect gate lead plug
PLG7 from receptacle RC7 on
control board PC1.
.Make sure meter probes make
good electrical contact. Black
painton bolts may act as an in-
sulator.
Test PM3 as follows:
3 Connect red tester lead to C1,
black tester lead to E1, and
yellow tester lead to gate
(PLG7–pin 12). Next, connect
red lead to C2, black lead to
E2, and yellow tester lead to
gate (PLG7–pin 3).
Test PM4 as follows:
4 Connect red tester lead to C1,
black lead to E1, and yellow
lead to gate (PLG7–pin 6).
Next, connect red lead to C2,
black lead to E2, and yellow
lead to gate (PLG7–pin 9).
Connect PLG7 to RC7.
AlternateTest For PM3 And PM4
(Use standard digital meter set to
ohms position) (Continued)
YRead and follow safety
information in Section 5-1
before proceeding.
1 Visually inspect PM3 and
PM4 for damage.
2 Disconnect gate lead plug
PLG7 from receptacle RC7 on
control board PC1.
.Make sure meter probes make
good electrical contact. Black
painton bolts may act as an in-
sulator.
3 For PM3 and PM4, measure
between C1 and E1, and then
between C2 and E2 (a high
resistance means device is
okay, zero ohms means
device is shorted)
4 For PM3, check for 100K
ohms resistance (+/–10%)
between the following:
E1 and PLG7–pin 12
E2 and PLG7–pin 3
5 For PM4, check for 100K
ohms resistance (+/–10%)
between the following:
E1 and PLG7–pin 6
E2 and PLG7–pin 9
Connect PLG7 to RC7.
Receptacle
RC7
Terminal
C2/E1
Terminal
E2
Terminal
C1
Terminal
C2/E1
Terminal
E2
Terminal
C1
Front Of Unit
Control Board PC1
ST-802 037 / ST-802 408 / SA-188 731-A
1
12 7
PLG7
Tab Lock
Bottom View
6

TM-357 Page 18 Dynasty DX
5-6. Diodes D1, D2, D3, D4
ST-801 550 / SC-183 621-A
YRead and follow safety
information in Section 5-1
before proceeding.
1 Check D1 and D2 on PC2 for
2000 ohms ±10% in 230/460
volt models or 400 ohms
±10% in 460/575 volt models
(ohms position).
2 Check D3 and D4 on PC2
(diode test).
Diode
D1
Interconnecting Board PC2
Diode
D2
Diode
D3 Diode D4