Miller Electric SYNCROWAVE 250 User manual

Processes
TM-353E January 2001
Eff. w/Serial Number JJ339876
Description
TIG (GTAW) Welding
Stick (SMAW) Welding
Arc Welding Power Source
Syncrowave 250
60 Hz, 50 Hz
R
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www.MillerWelds.com

TABLE OF CONTENTS
1. Safety Precautions – Read Before Using 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.1 Symbol Usage 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 Servicing Hazards 1. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.3 EMF Information 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 2 – DEFINITIONS 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-1. Warning Label Definitions 3. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-2. Rating Label For CE Products 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2-3. Symbols And Definitions 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 3 – INSTALLATION 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-1. Specifications 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-2. Volt-Ampere Curves 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-3. Duty Cycle And Overheating 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-4. Selecting A Location 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-5. Dimensions And Weights 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-6. Tipping 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-7. Weld Output Terminals And Selecting Cable Sizes 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-8. Remote 14 Receptacle 10. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-9. 115 Volts AC Duplex Receptacle And Shielding Gas Connections 10. . . . . . . . . . . . . . . . . . . . . .
3-10.Electrical Service Guide 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3-11.Placing Jumper Links And Connecting Input Power 12. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 4 – OPERATION 13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-1. Controls 13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-2. Output Selector Switch 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-3. Meters 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-4. Crater Time Controls 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-5. Spot Time Controls 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-6. AC Balance Control 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-7. Amperage Adjustment Controls 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-8. Output (Contactor) Control Switch 17. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-9. Arc Controls 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-10.Postflow Time Control 18. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-11.High Frequency Controls 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4-12.Preflow Time Control (Optional) 19. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 5 – THEORY OF OPERATION 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 6 – TROUBLESHOOTING 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-1. Troubleshooting Table 22. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-2. Troubleshooting Circuit Diagram For Welding Power Source 26. . . . . . . . . . . . . . . . . . . . . . . . . .
6-3. Waveforms For Section 6-2 28. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-4. Control Board PC1 Testing Information (Use With Section 6-5) 30. . . . . . . . . . . . . . . . . . . . . . . .
6-5. Control Board PC1 Test Point Values 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-6. Remote Board PC2 Testing Information (Use With Section 6-7) 33. . . . . . . . . . . . . . . . . . . . . . . .
6-7. Remote 14 Filter Board PC2 Test Point Values (Use With Section 6-2 And Section 6-6) 34. . . .
6-8. Meter Calibration 35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6-9. Input Voltage Labels And Connections 36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 7 – MAINTENANCE 37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7-1. Routine Maintenance 37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7-2. Circuit Breaker CB1 37. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7-3. Fuses F1 And F2 38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7-4. Adjusting Spark Gaps 38. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 8 – HIGH FREQUENCY (HF) 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8-1. Welding Processes Using HF 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8-2. Sources Of HF Radiation From Incorrect Installation 39. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8-3. Correct Installation 40. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 9 – ELECTRICAL DIAGRAMS 41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SECTION 10 – PARTS LIST 68. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TM-353D

dec_con1 10/95
Declaration of Conformity For
European Community (CE) Products
This information is provided for units with CE certification (see rating label on unit.)
NOTE
Manufacturer’s Name: Miller Electric Mfg. Co.
Manufacturer’s Address: 1635 W. Spencer Street
Appleton, WI 54914 USA
Declares that the product: Syncrowave250
conforms to the following Directives and Standards:
Directives
Low Voltage Directive: 73/23/EEC
Machinery Directives: 89/392/EEC, 91/368/EEC, 93/C 133/04, 93/68/EEC
Electromagnetic Capability Directives: 89/336, 92/31/EEC
Standards
Safety Requirements for Arc Welding Equipment part 1: EN 60974-1: 1990
Arc Welding Equipment Part 1: Welding Power Sources: IEC 974-1
(April 1995 – Draft revision)
Degrees of Protection provided by Enclosures (IP code): IEC 529: 1989
Insulation coordination for equipment within low-voltage systems:
Part 1: Principles, requirements and tests: IEC 664-1: 1992
Electromagnetic compatibility (EMC) Product standard for arc welding equipment:
EN50199: August 1995
European Contact: Mr. Luigi Vacchini, Managing Director
MILLER Europe S.P.A.
Via Privata Iseo
20098 San Giuliano
Milanese, Italy
Telephone: [phone]
Fax: [phone]

TM-353 Page 1Syncrowave 250
SECTION 1 –SAFETY PRECAUTIONS FOR SERVICING
safety_stm1 4/95
1-1. Symbol Usage
Means Warning! Watch Out! There are possible hazards with this
procedure!The possible hazards are shown in the adjoining symbols.
This group of symbols means Warning! Watch Out! possible ELECTRIC SHOCK, MOVING PARTS,
and HOT PARTS hazards. Consult symbols and related instructions below for necessary actions to
avoid the hazards.
YMarks a special safety message.
.Means NOTE; not safety related.
1-2. Servicing Hazards
ELECTRIC SHOCK can kill.
1. Do not touch live electrical parts.
2. Stopengine or turn OFF welding power source and
wire feeder, and disconnect and lockout input
power using line disconnect switch, circuit
breakers, or by removing plug from receptacle
beforeservicing unless the procedure specifically
requires an energized unit.
3. Insulate yourself from ground by standing or
working on dry insulating mats big enough to
preventcontact with the ground.
4. Do not leave live unit unattended.
5. Whentesting a live unit, use the one-hand method.
Do not put both hands inside unit. Keep one hand
free.
6. Disconnect input power conductors from
deenergized supply line BEFORE moving a
weldingpower source.
SIGNIFICANT DC VOLTAGE exists after
removal of input power on inverters.
7. Turn Off inverter, disconnect input power, and
discharge input capacitors according to
instructions in Maintenance Section before
touchingany parts.
STATIC ELECTRICITY can damage
parts on circuit boards.
1. Put on grounded wrist strap BEFORE handling
boards or parts.
2. Use proper static-proof bags to store, move, or ship
PC boards.
FIRE OR EXPLOSION can result from
placing unit on, over, or near
combustible surfaces.
1. Do not place unit on, over, or near combustible
surfaces.
2. Do not service unit near flammables.
FLYING PIECES OF METAL or DIRT can
injure eyes.
1. Wear safety glasses with side shields or face shield
duringservicing.
2. Be careful not to short metal tools, parts, or wires
together during testing and servicing.
HOT PARTS can cause severe burns.
1. Do not touch hot parts bare handed.
2. Allow cooling period before servicing welding gun
or torch.
EXPLODING PARTS can cause injury.
1. Failed parts can explode or cause other parts to
explodewhen power is applied to inverters.
2. Always wear a face shield and long sleeves when
servicing inverters.
ELECTRIC SHOCK HAZARD from
incorrect use of test equipment.
1. Turn Off welding power source and wire feeder or
stop engine before making or changing meter lead
connections.
2. At least one meter lead should be a self-retaining
spring clip such as an alligator clamp.
3. Read instructions for test equipment.
HIGH-FREQUENCY RADIATION can
interfere with radio navigation, safety
services, computers, and
communications equipment.
1. Have only qualified persons familiar with electronic
equipmentperform this installation.
2. The user is responsible for having a qualified
electrician promptly correct any interference
problemresulting from the installation.
3. If notified by the FCC about interference, stop using
the equipment at once.
4. Have the installation regularly checked and
maintained.
5. Keep high-frequency source doors and panels
tightlyshut, keep spark gaps at correct setting, and
use grounding and shielding to minimize the
possibilityof interference.
The 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.
Only qualified persons should service, test, maintain, and repair this unit.
During servicing, keep everybody, especially children, away.
WARNING

TM-353 Page 2 Syncrowave 250
FALLING EQUIPMENT can cause
serious personal injury and equipment
damage.
1. Use lifting eye to lift unit only, NOT running gear,
gas cylinders, or any other accessories.
2. Use equipment of adequate capacity to lift unit.
MAGNETIC FIELDS FROM HIGH
CURRENTS can affect pacemaker
operation.
1. Pacemaker wearers keep away from servicing
areas until consulting your doctor.
MOVING PARTS can cause injury.
1. Keep away from moving parts such as fans.
2. Keepall doors, panels, covers, and guards closed
and securely in place.
MOVING PARTS can cause injury.
1. Keep away from moving parts.
2. Keep away from pinch points such as drive rolls.
OVERUSE can cause OVERHEATED
EQUIPMENT.
1. Allow cooling period.
2. Reduce current or reduce duty cycle before
startingto weld again.
3. Follow rated duty cycle.
READ INSTRUCTIONS.
1. Use MILLER Testing Booklet (Part No. 150 853)
when servicing this unit.
2. Consult the Owner’s Manual for welding safety
precautions.
3. Use only genuine MILLER replacement parts.
1-3. EMF Information
ConsiderationsAbout Welding And The Effects Of Low Frequency
Electric And Magnetic Fields
The following is a quotation from the General Conclusions Section of
the U.S. Congress, Office of Technology Assessment, Biological
Effects of Power Frequency Electric & Magnetic Fields –Background
Paper, OTA-BP-E-53 (Washington, DC: U.S. Government Printing
Office, May 1989): “. . . there is now a very large volume of scientific
findingsbased on experiments at the cellular level and from studies
with animals and people which clearly establish that low frequency
magneticfields can interact with, and produce changes in, biological
systems. While most of this work is of very high quality, the results are
complex.Current scientific understanding does not yet allow us to
interpretthe evidence in a single coherent framework. Even more
frustrating,it does not yet allow us to draw definite conclusions about
questionsof possible risk or to offer clear science-based advice on
strategies to minimize or avoid potential risks.”
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 the body.
4. Keep welding power source and cables as far away as
practical.
5. Connect work clamp to workpiece as close to the weld as
possible.
About Pacemakers:
The above procedures are also recommended for pacemaker
wearers. Consult your doctor for complete information.

TM-353 Page 3Syncrowave 250
SECTION 2 –DEFINITIONS
2-1. Warning Label Definitions
S-176 254-A
1 1.1 1.2 1.3
3 3.1 3.2 3.3
4 4.1 +
22.1 2.2
+
+
5 6
+
2.3
Warning! Watch Out! There are
possible hazards as shown by the
symbols.
1 Electric shock from welding
electrode or wiring can kill.
1.1 Wear dry insulating gloves.
Do not touch electrode with
bare hand. Do not wear wet or
damaged gloves.
1.2 Protect yourself from electric
shock by insulating yourself
from work and ground.
1.3 Disconnect input plug or
power before working on
machine.
2 Breathing welding fumes can
be hazardous to your health.
2.1 Keep your head out of the
fumes.
2.2 Use forced ventilation or local
exhaust to remove the fumes.
2.3 Use ventilating fan to remove
fumes.
3 Welding sparks can cause
explosion or fire.
3.1 Keep flammables away from
welding. Don’t weld near
flammables.
3.2 Welding sparks can cause
fires. Have a fire extinguisher
nearby and have a watch
person ready to use it.
3.3 Do not weld on drums or any
closed containers.
4 Arc rays can burn eyes and
injure skin.
4.1 Wear hat and safety glasses.
Use ear protection and button
shirt collar. Use welding
helmet with correct shade of
filter. Wear complete body
protection.
5 Become trained and read the
instructions before working on
the machine or welding.
6 Do not remove or paint over
(cover) the label.

TM-353 Page 4 Syncrowave 250
2-2. Rating Label For CE Products
S-178 813-A
ISO/IEC 974-1
X 25% 60% 100%
7A/10.2V 310A/22.4V
U0= 80V I2310A 200A 155A
U222.4V 18V 16.2V
X 25% 60% 100%
5A/20.2V 310A/32.4V
U0= 80V I2310A 200A 155A
U232.4V 28V 26.2V
IP 21S
U1= 220 I1max = 117.2A I1Eff = 59A
1
11
50 Hz U1= 380 I1max = 72.2A I1Eff = 36A
U1= 415 I1max = 63.8A I1Eff = 32A

TM-353 Page 5Syncrowave 250
2-3. Symbols And Definitions
Some symbols are found only on CE products.
NOTE
AAmperes Panel–Local Gas Tungsten Arc
Welding (GTAW) Shielded Metal Arc Welding (SMAW)
VVolts Do Not Switch
While Welding Arc Force (DIG) Spot Timer
Output Circuit Breaker Remote Temperature
Protective Earth
(Ground) Alternating Current High Frequency - Start Input
Postflow Timer Preflow Timer High Frequency -
Continuous High Frequency
Gas (Supply) Gas Input Gas Output Increase/Decrease
Of Quantity
On Off Percent Direct Current
Balance Control Maximum Cleaning Maximum
Penetration Electrode Positive
Electrode
Negative Crater Time Meter Single-Phase
U0Rated No Load
Voltage (Average) U1Primary Voltage U2Conventional Load Voltage Line Connection
I1Primary Current I2Rated Welding
Current XDuty Cycle 11Single-Phase
Combined AC/DC
Power Source
IP Degree Of
Protection I1eff Maximum Effective Supply Current I1max Rated Maximum Supply Current Hz Hertz
Electrode Work Thickness Gauge Spark Gap
SSeconds

TM-353 Page 6 Syncrowave 250
SECTION 3 –INSTALLATION
3-1. Specifications
Amperes Input at AC Balanced
Rated Load Output,
50/60 Hz, Single-Phase
Rated
Welding Output PFC** 200 V 230 V 460 V 575 V KVA KW Amp Range Max OCV IP Rating
NEMA Class II
(40) –250 No
PFC 106 (4.6*) 92 (4*) 46 (2*) 37 (1.6*) 21 (0.89*) 11.4 (0.68*)
Amperes, 30 Volts
AC, 40% Duty
Cycle With
PFC 76 66 33 26 15.2 11.4 5–310 A 80 V 21
*While idling
**Power Factor Correction
Rated
Amperes Input at AC Balanced
Rated Load Output,
50/60 Hz, Single-Phase
Rated
Welding
Output PFC
** 200
V220 V230 V260 V380 V415 V460 V520 V575 VKVA KW Amp
Range Max OCV IP Rating
NEMA
Class I
(60) –200 No
PFC 85 (4.6*) 77 (4.2*) 74 (4*) 65 (3.5*) 45 (2.4*) 41 (2.2*) 37 (2*) 33 (1.8*) 30 (1.6*) 17 (0.9*) 8.3 (0.7*)
Amperes,
28 Volts
AC, 60%
Duty Cycle
With
PFC 55 (57*) 64 (51*) 48 (49*) 48 (49*) 37 (30*) 34 (27*) 24 (25*) 48 (49*) 19 (20*) 11 (11*) 8.3 (0.6*)
5–310 A 80 V 21
*While idling
**Power Factor Correction
3-2. Volt-Ampere Curves
The volt-ampere curves show the
minimum and maximum voltage
and amperage output capabilities of
the welding power source. Curves
of other settings fall between the
curves shown.
ssb1.1 10/91 –SB-116 199 / SB-116 200
A. DC Mode B. AC Mode

TM-353 Page 7Syncrowave 250
3-3. Duty Cycle And Overheating
4 Minutes Welding 6 Minutes Resting
6 Minutes Welding 4 Minutes Resting
Duty Cycle is percentage of 10 min-
utes that unit can weld at rated load
withoutoverheating.
If unit overheats, thermostat opens,
output stops, light goes on (CE
modelsonly), and cooling fan runs.
Wait fifteen minutes for unit to cool.
Reduceamperage or duty cycle be-
fore welding.
YExceeding duty cycle can
damage unit and void
warranty.
40% Duty Cycle At 250 Amperes (60 Hz Models Only)
Overheating
0
15
A
OR
Reduce Duty Cycle
Minutes
duty1 4/95 / SB-116 198
60% Duty Cycle At 200 Amperes

TM-353 Page 8 Syncrowave 250
3-4. Selecting A Location
1 LiftingEye
2 Lifting Forks
Use lifting eye or lifting forks to
move unit.
If using lifting forks, extend forks
beyondopposite side of unit.
3 Rating Label (Non CE Models
Only)
4 Rating Label (CE Models
Only, See Section 2-2)
Use rating label to determine input
power needs. CE label located on
rear panel.
5 Plate Label (CE Models Only)
6 Line Disconnect Device
Locateunit near correct input pow-
er supply.
YSpecial installation may be
required where gasoline or
volatileliquids are present –
see NEC Article 511 or CEC
Section20.
1
2
Movement
ST-800 402 / ST-117 264-F
6
18 in (460
mm)
Location And Airflow
OR
18 in (460
mm)
3
5
4
3-5. Dimensions And Weights
Dimensions
AHeight 30-3/4in (781 mm)
BCWidth 19-3/4in (502 mm)
E
DLength 27-1/2in (698 mm)
A27 in (686 mm)
B26 in (661 mm)
FC25-1/4in (642 mm) F
Front D1-1/2in (38 mm)
GE 1-1/8(29 mm)
F 17-7/8(454 mm)
G 19-1/4(489 mm)
H1/2 in (13 mm) Dia
6 Holes
HWeight
ST-154 792-B 355 lbs (161 kg)

TM-353 Page 9Syncrowave 250
3-6. Tipping
YBe careful when placing or
moving unit over uneven
surfaces.
3-7. Weld Output Terminals And Selecting Cable Sizes
YARC WELDING can cause Electromagnetic Interference.
To reduce possible interference, keep weld cables as short as possible, close together, and down low, such as on the floor.
Locatewelding operation 100 meters from any sensitive electronic equipment. Be sure this welding machine is installed
and grounded according to this manual. If interference still occurs, the user must take extra measures such as moving
the welding machine, using shielded cables, using line filters, or shielding the work area.
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
350 1/0 2/0 3/0 4/0 2-2/0 2-3/0 2-3/0 2-4/0
400 1/0 2/0 3/0 4/0 2-2/0 2-3/0 2-4/0 2-4/0
ElectrodeWork
ST-154 795-C 500 2/0 3/0 4/0 2-2/0 2-3/0 2-4/0 3-3/0 3-3/0
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 dis-
tributor for the mm2equivalent weld cable sizes. S-0007-E

TM-353 Page 10 Syncrowave 250
3-8. Remote 14 Receptacle
Socket* Socket Information
A24 volts ac.
BContact closure to A completes 24 volts ac contactor control
circuit.
CCommandreference; 0 to +10 volts dc output to remote control.
AJ
BKIDRemotecontrol circuit common.
CLNH
DMG
F
AE0 to +10 volts dc input command signal from remote control.
EF
ST-154 795-C K Chassis common.
*The remaining sockets are not used.
3-9. 115 Volts AC Duplex Receptacle And Shielding Gas Connections
Ref. ST-154 795-C / Ref. ST-157 858
YTurn Off power before
connectingto receptacle.
1 115 V AC Receptacle
Receptacle is protected from over-
load by circuit breaker CB1 (see
Section7-2).
2 Gas Valve In Fitting
3 Gas Valve Out Fitting
Fittings have 5/8-18 right-hand
threads
4 CylinderValve
Open valve slightly so gas flow
blows dirt from valve. Close valve.
5 Regulator/Flow Gauge
6 Flow Adjust
Typical flow rate is 20 cfh (cubic feet
per hour) (9.4 L/min)
7 High Frequency Control (see
Section 4-1)
4
5
6
1 7
3 2

TM-353 Page 11Syncrowave 250
3-10. Electrical Service Guide
All values calculated at 60% duty cycle.
NOTE
60 Hertz Models Without Power Factor
Correction With Power Factor Correction
Input Voltage 200 230 460 575 200 230 460 575
Input Amperes At Rated Output 85 74 37 30 55 48 24 19
Max Recommended Standard Fuse Or Circuit
Breaker Rating In Amperes 125 110 60 45 80 70 35 30
Min Input Conductor Size In AWG/Kcmil 4 6 10 10 8 8 12 14
Max Recommended Input Conductor Length
In Feet (Meters) 173
(53) 158 (48) 291 (89) 455 (139) 86 (26) 114 (35) 186 (58) 189 (48)
Min Grounding Conductor Size In AWG/Kcmil 6 6 10 10 8 8 12 14
Reference:1996 National Electrical Code (NEC) S-0092-J
50 Hertz Models Without Power Factor Correction With Power Factor
Correction
Input Voltage 220 260 380 415 520 220 380 415
Input Amperes At Rated Output 77 65 45 41 33 64 37 34
Max Recommended Standard Fuse Or Circuit
Breaker Rating In Amperes 125 100 70 60 50 90 60 50
Min Input Conductor Size In AWG/Kcmil 6 6 8 8 10 6 10 10
Max Recommended Input Conductor Length
In Feet (Meters) 145
(44) 202 (62) 291 (89) 347 (106) 372 (113) 145 (44) 291 (89) 347 (106)
Min Grounding Conductor Size In AWG/Kcmil 6 8 8 10 10 6 8 10
Reference: 1996 National Electrical Code (NEC) S-0092-J

TM-353 Page 12 Syncrowave 250
1
3-11. Placing Jumper Links And Connecting Input Power
ST-117 263-K
Check input voltage available at
site.
1 JumperLink Label
Check label inside your unit–
only one label is on unit.
YOnly make connections for
the voltages shown on the la-
bel inside your unit. Do not
make connections for any
other voltages. If jumper link
label is missing from inside
unit, check rating label (see
Section 3-4) for allowable in-
put voltages.
2 Jumper Links
Move jumper links to match input
voltage.
3 InputAnd Grounding
Conductors
Select size and length using
Section3-10.
4 Line Disconnect Device
Select type and size of overcurrent
protection using Section 3-10.
Reinstall side panel.
YSpecial installation may be
required where gasoline or
volatileliquids are present –
see NEC Article 511 or CEC
Section20.
3/8 in
3/8, 1/2, 7/16 in
Tools Needed:
230 VOLTS
LL
460 VOLTS
LL
S-010 587-B
575 VOLTS
LL
230 VOLTS 460 VOLTS200 VOLTS
LL LL LL
S-083 566-C
2
L1 (U)
L2 (V)
GND/PE
Earth Ground
4
3
220 VOLTS
LL
380 VOLTS
LL
S-131 783-A
415 VOLTS
LL
Connect GND/PE
ConductorFirst
Connect GND/PE
ConductorFirst
S-047 672-A
260 VOLTS
LL
380 VOLTS
LL
520 VOLTS
LL

TM-353 Page 13Syncrowave 250
SECTION 4 –OPERATION
4-1. Controls
Ref. ST-117 264-F / Ref. ST-154 795-C
15
14
13
12
11
10
9
87
6
5
4
3
2
1
1 Ammeter
See Section 4-3.
2 Voltmeter
See Section 4-3.
3 High Frequency Switch
See Section 4-11.
4 Output (Contactor) Switch
See Section 4-8.
5 Spot Time Switch And Control
(Optional)
See Section 4-5.
6 Preflow Time Control (Optional)
See Section 4-12.
7 AC Balance Control
See Section 4-6.
8 Crater Time Control And Switch
See Section 4-4.
9 Amperage Adjustment Control And
Switch
See Section 4-7.
10 Arc Force (Dig) Switch And Control
See Section 4-9.
11 Postflow Time Control
See Section 4-10.
12 High Temperature Shutdown Light
(CE Models Only)
Lights when unit overheats and shuts
down (see Section 3-3).
13 Power Switch And Pilot Light
Use switch to turn unit and light On and
Off.
14 Output Selector Switch
See Section 4-2.
15 High Frequency Control
See Section 4-11.

TM-353 Page 14 Syncrowave 250
4-2. Output Selector Switch
Ref. ST-181 675-A
1 Output Selector Switch
YDo not use AC output in
damp areas, if movement is
confined, or if there is dan-
ger of falling. Use AC output
ONLY if required for the
welding process, and then
use a remote control.
YDo not change position of
switch while welding or
while under load.
Use switch to select (DCEN) Direct
CurrentElectrode Negative, AC, or
(DCEP) Direct Current Electrode
Positive output without changing
weld output cable connections.
1
4-3. Meters
1 Voltmeter
Voltmeter displays voltage at the
weld output terminals, but not nec-
essarily the welding arc due to
cable resistance, poor connec-
tions, etc.
2 Ammeter
Ammeter displays weld amperage
outputof unit.
1 2

TM-353 Page 15Syncrowave 250
4-4. Crater Time Controls
1 Crater Time Control
Use control to reduce current over a
set period of time (0–15 seconds) at
the end of the weld cycle when NOT
using a remote current control.
2 Crater Time Switch
ON –provides crater time.
OFF –provides no crater time.
Place switch in the OFF position for
Shielded Metal Arc Welding
(SMAW).
Application:
Crater Time should be used while
GTAW welding materials that are
crack sensitive, and/or the operator
wants to eliminate the crater at the
end of the weld.
Note: This applies if the operator is
using an on/off only type control to
start and stop the welding process.
2
1
4-5. Spot Time Controls
1 Spot Time Switch
Place switch in the ON position to
turn on spot weld circuitry.
The (GTAW) TIG Spot process is
generallyused with a direct current
electrodenegative (DCEN) set-up.
Place switch in the OFF position to
turn off spot weld circuitry. Put
switch in the OFF position while do-
ing Shielded Metal Arc Welding
(SMAW).
2 Spot Time Control
Use control to set time (0–5.7 sec-
onds) for Gas Tungsten Arc
(GTAW) spot welds. Spot time be-
gins at arc initiation. If the arc is bro-
ken during the spot time cycle, the
timer stops but does not reset.
When the spot time has ended,
weld output stops. Postflow starts
when the remote contactor is
opened.The spot timer resets after
the contactor opens.
Application:
TIG spot welding is used for joining
thinner materials that are in close
contact, with the fusion method. A
goodexample would be joining coil
ends.
1
2

TM-353 Page 16 Syncrowave 250
4-6. AC Balance Control
Ref. S-0795-A
1 AC Balance Control
Balance Control (AC GTAW):
Control changes the AC output
square wave. Rotating the control
towards 10 provides deeper pene-
tration.Rotating the control towards
0 provides more cleaning action of
the workpiece.
Whenthe control is in the Balanced
position,the wave shape provides
equal penetration and cleaning
action.
Application:
Whenwelding on oxide forming ma-
terials such as aluminum or magne-
sium, excess cleaning is not neces-
sary. To produce a good weld, only
a minimal amount, approximately a
0.10 in (2.5mm) of etched zone
alongthe weld toes is required.
Set control to 7 and adjust as nec-
essary. Joint configuration, set-up,
process variables, and oxide thick-
ness may affect setting.
Arc rectification can occur when
welding above 200 amps and/or
whilewelding with helium gas. If this
condition occurs, increasing the
Balancecontrol towards maximum
penetration,may help to restabilize
the arc.
Balanced
3
10
0
More Penetration
More Cleaning
50% Electrode
Positive
50% Electrode
Negative
32% Electrode
Positive
68% Electrode
Negative
55% Electrode
Positive
45% Electrode
Negative
Output Waveforms ArcSetting
1