Thermal Dynamics Pak Master 75XL Plus User manual

PLASMA CUTTING
POWER SUPPLY
Pak Master®75XL™ Plus
Service Manual
September 15, 2003 Manual No. 0-2747
A-02464

Plasma Cutting Power Supply
Pak Master®75XLTM Plus
Service Manual Number 0-2747
Published by:
Thermal Dynamics Corporation
82 Benning Street
West Lebanon, New Hampshire, USA 03784
[phone]
www.thermal-dynamics.com
Copyright 1999 by
Thermal Dynamics Corporation
All rights reserved.
Reproduction of this work, in whole or in part, without written per-
mission of the publisher is prohibited.
The publisher does not assume and hereby disclaims any liability to
any party for any loss or damage caused by any error or omission in
this Manual, whether such error results from negligence, accident, or
any other cause.
Printed in the United States of America
Publication Date: September 15, 2003
Record the following information for Warranty purposes:
Where Purchased: _______________________________________
Purchase Date: _______________________________________
Power Supply Serial #: _______________________________________
Torch Serial #: _______________________________________
WARNINGS
Read and understand this entire Manual and your employer’s safety practices before installing, oper-
ating, or servicing the equipment.
While the information contained in this Manual represents the Manufacturer's best judgement, the
Manufacturer assumes no liability for its use.

TABLE OF CONTENTS
SECTION 1:
GENERAL INFORMATION ............................................................................................... 1-1
1.01 Notes, Cautions andWarnings ..................................................................... 1-1
1.02 Important Safety Precautions ....................................................................... 1-1
1.03 Publications.................................................................................................. 1-2
1.04 Note, Attention et Avertissement .................................................................. 1-3
1.05 Precautions De Securite Importantes........................................................... 1-3
1.06 Documents De Reference ............................................................................ 1-5
1.07 Declaration of Conformity............................................................................. 1-7
1.08 Statement ofWarranty.................................................................................. 1-8
SECTION 2:
INTRODUCTION ................................................................................................................. 1
2.01 Scope Of Manual ............................................................................................ 1
2.02 General Service Philosophy ............................................................................ 1
2.03 Service Responsibilities .................................................................................. 1
SECTION 3:
DESCRIPTION ................................................................................................................. 3-1
3.01 Scope........................................................................................................... 3-1
3.02 General Description of System..................................................................... 3-1
3.03 Specifications/DesignFeatures .................................................................... 3-1
3.04 Power Supply Options and Accessories....................................................... 3-2
Section 4:
TROUBLESHOOTING ...................................................................................................... 4-1
4.01 Introduction .................................................................................................. 4-1
4.02 Periodic Inspection & Procedures ................................................................ 4-1
4.03 Common Operating Problems ...................................................................... 4-1
4.04 Troubleshooting Guide - General Information ............................................... 4-2
4.05 Circuit Fault Isolation .................................................................................... 4-3
4.06 Main Input and Internal Power Problems...................................................... 4-4
4.07 Pilot Arc Problems........................................................................................ 4-7
4.08 Main Arc Problems....................................................................................... 4-8
4.09 Test Procedures ........................................................................................... 4-9
SECTION 5:
REPLACEMENT PROCEDURES .................................................................................... 5-1
5.01 Introduction .................................................................................................. 5-1
5.02 Anti-Static Handling Procedures................................................................... 5-1
5.03 Parts Replacement - General Information .................................................... 5-1
5.04 Major External Parts Replacement............................................................... 5-2
5.05 Access Panel Parts Replacement ................................................................ 5-2
5.06 Front Panel Parts Replacement.................................................................... 5-3
5.07 Left Side Internal Component Parts Replacement........................................ 5-4
5.08 Rear Panel Parts Replacement .................................................................... 5-6
5.09 Right Side Internal Component Parts Replacement ..................................... 5-8

TABLE OF CONTENTS (continued)
SECTION 6:
REPLACEMENT PARTS ................................................................................................... 6-1
6.01 Introduction ................................................................................................. 6-1
6.02 Ordering Information ................................................................................... 6-1
6.03 Major External Replacement Parts.............................................................. 6-2
6.04 Access Panel Replacement Parts ............................................................... 6-3
6-3
6.05 Front Panel Replacement Parts................................................................... 6-4
6.06 Left Side Internal Component Replacement Parts....................................... 6-6
6.07 Rear Panel Replacement Parts ................................................................... 6-8
6.08 Right Side Internal Component Replacement Parts .................................. 6-10
6.09 Options and Accessories........................................................................... 6-12
APPENDIX 1: INPUT WIRING REQUIREMENTS ....................................................................A-1
APPENDIX 2: SEQUENCE OF OPERATION (BLOCK DIAGRAM) .........................................A-2
APPENDIX 3: POT/LED PC BOARD LAYOUT..........................................................................A-3
APPENDIX 4: LOGIC/GATE PC BOARD LAYOUT ...................................................................A-4
APPENDIX 5: PILOT OUTPUT PC BOARD LAYOUT...............................................................A-6
APPENDIX 6: CD PC BOARD LAYOUT ...................................................................................A-8
APPENDIX 7: INPUT PC BOARD LAYOUT ..............................................................................A-9
APPENDIX 8: FET PC BOARD LAYOUT................................................................................A-10
APPENDIX 9: CAPACITOR PC BOARD LAYOUT...................................................................A-12
APPENDIX 10: 36VAC CIRCUIT DIAGRAM ...........................................................................A-13
APPENDIX 11: MAINTENANCE SCHEDULE .......................................................................A-14
APPENDIX 12: SYSTEM SCHEMATIC...................................................................................A-16

Date: November 15, 2001 1-1 GENERAL INFORMATION
SECTION 1:
GENERAL INFORMATION
1.01 Notes, Cautions and Warnings
Throughout this manual, notes, cautions, and warnings
areused to highlight important information. These high-
lights are categorized as follows:
NOTE
An operation, procedure, or background informa-
tion which requires additional emphasis or is help-
ful in efficient operation of the system.
CAUTION
A procedure which, if not properly followed, may
cause damage to the equipment.
WARNING
A procedure which, if not properly followed, may
cause injury to the operator or others in the oper-
ating area.
1.02 Important Safety Precautions
WARNINGS
OPERATION AND MAINTENANCE OF
PLASMA ARC EQUIPMENT CAN BE DAN-
GEROUS AND HAZARDOUS TO YOUR
HEALTH.
Plasma arc cutting produces intense electric and
magnetic emissions that may interfere with the
proper function of cardiac pacemakers, hearing
aids, or other electronic health equipment. Per-
sons who work near plasma arc cutting applica-
tions should consult their medical health profes-
sional and the manufacturer of the health
equipment to determine whether a hazard exists.
To prevent possible injury, read, understand and
follow all warnings, safety precautions and in-
structionsbeforeusing the equipment. Call 1-603-
298-5711 or your local distributor if you have any
questions.
GASES AND FUMES
Gases and fumes produced during the plasma cutting
process can be dangerous and hazardous to your health.
• Keep all fumes and gases from the breathing area.
Keep your head out of the welding fume plume.
• Use an air-supplied respirator if ventilation is not
adequate to remove all fumes and gases.
• The kinds of fumes and gases from the plasma arc
depend on the kind of metal being used, coatings
onthe metal, and the different processes. You must
be very careful when cutting or welding any met-
als which may contain one or more of the follow-
ing:
Antimony Chromium Mercury
Arsenic Cobalt Nickel
Barium Copper Selenium
Beryllium Lead Silver
Cadmium Manganese Vanadium
• Always read the Material Safety Data Sheets
(MSDS) that should be supplied with the material
you are using. These MSDSs will give you the in-
formationregarding the kind and amount of fumes
and gases that may be dangerous to your health.
• For information on how to test for fumes and gases
inyour workplace, referto item 1inSubsection1.03,
Publications in this manual.
• Usespecialequipment, such as water or down draft
cutting tables, to capture fumes and gases.
• Do not use the plasma torch in an area where com-
bustible or explosive gases or materials are located.
• Phosgene, a toxic gas, is generated from the vapors
of chlorinated solvents and cleansers. Remove all
sources of these vapors.
• This product, when used for welding or cutting,
produces fumes or gases which contain chemicals
known to the State of California to cause birth de-
fects and, in some cases, cancer. (California Health
& Safety Code Sec. 25249.5 et seq.)
ELECTRIC SHOCK
Electric Shock can injure or kill. The plasma arc process
uses and produces high voltage electrical energy. This
electric energy can cause severe or fatal shock to the op-
erator or others in the workplace.
• Never touch any parts that are electrically “live”
or “hot.”

GENERAL INFORMATION 1-2 Date: November 15, 2001
• Wear dry gloves and clothing. Insulate yourself
from the work piece or other parts of the welding
circuit.
• Repair or replace all worn or damaged parts.
• Extra care must be taken when the workplace is
moist or damp.
• Install and maintain equipment according to NEC
code, refer to item 9 in Subsection 1.03, Publica-
tions.
• Disconnect power source before performing any
service or repairs.
• Read and follow all the instructions in the Operat-
ing Manual.
FIRE AND EXPLOSION
Fire and explosion can be caused by hot slag, sparks, or
the plasma arc.
• Be sure there is no combustible or flammable ma-
terial in the workplace. Any material that cannot
be removed must be protected.
• Ventilate all flammable or explosive vapors from
the workplace.
• Do not cut or weld on containers that may have
held combustibles.
• Provideafire watchwhenworkingin an areawhere
fire hazards may exist.
• Hydrogen gas may be formed and trapped under
aluminum workpieces when they are cut under-
water or while using a water table. DO NOT cut
aluminum alloys underwater or on a water table
unless the hydrogen gas can be eliminated or dis-
sipated. Trapped hydrogen gas that is ignited will
cause an explosion.
NOISE
Noisecancausepermanenthearingloss. Plasma arcpro-
cesses can cause noise levels to exceed safe limits. You
must protect your ears from loud noise to prevent per-
manent loss of hearing.
• To protect your hearing from loud noise, wear pro-
tective ear plugs and/or ear muffs. Protect others
in the workplace.
• Noiselevels should be measuredto be surethe deci-
bels (sound) do not exceed safe levels.
• For information on how to test for noise, see item 1
in Subsection 1.03, Publications, in this manual.
PLASMAARC RAYS
PlasmaArcRayscaninjureyour eyes andburnyourskin.
The plasma arc process produces very bright ultra violet
and infra red light. These arc rays will damage your
eyesandburn your skin if youarenotproperlyprotected.
• To protect your eyes, always wear a welding hel-
metorshield. Alsoalwayswearsafety glasses with
side shields, goggles or other protective eye wear.
• Wear welding gloves and suitable clothing to pro-
tect your skin from the arc rays and sparks.
• Keep helmet and safety glasses in good condition.
Replace lenses when cracked, chipped or dirty.
• Protect others in the work area from the arc rays.
Use protective booths, screens or shields.
• Use the shade of lens as suggested in the following
per ANSI/ASC Z49.1:
Minimum Protective Suggested
Arc Current Shade No. Shade No.
Less Than 300* 8 9
300 - 400* 9 12
400 - 800* 10 14
* Thesevaluesapplywherethe actual arcisclearly
seen. Experience has shown that lighter filters
may be used when the arc is hidden by the work-
piece.
1.03 Publications
Refer to the following standards or their latest revisions
for more information:
1. OSHA, SAFETYAND HEALTH STANDARDS, 29CFR
1910, obtainable from the Superintendent of Docu-
ments, U.S. Government Printing Office, Washington,
D.C. 20402
2. ANSI Standard Z49.1, SAFETY IN WELDING AND
CUTTING, obtainable from theAmerican Welding So-
ciety, 550 N.W. LeJeune Rd, Miami, FL 33126
3. NIOSH, SAFETY AND HEALTH IN ARC WELDING
AND GAS WELDING AND CUTTING, obtainable
from the Superintendent of Documents, U.S. Govern-
ment Printing Office, Washington, D.C. 20402
4. ANSI Standard Z87.1, SAFE PRACTICES FOR OCCU-
PATION AND EDUCATIONAL EYEAND FACE PRO-
TECTION, obtainable from American National Stan-
dards Institute, 1430 Broadway, New York, NY 10018
5. ANSI Standard Z41.1, STANDARD FOR MEN’S
SAFETY-TOEFOOTWEAR, obtainable fromtheAmeri-
can National Standards Institute, 1430 Broadway, New
York, NY 10018

Date: November 15, 2001 1-3 GENERAL INFORMATION
6. ANSI StandardZ49.2, FIREPREVENTION IN THEUSE
OF CUTTING AND WELDING PROCESSES, obtain-
able from American National Standards Institute, 1430
Broadway, New York, NY 10018
7. AWS StandardA6.0, WELDINGAND CUTTING CON-
TAINERS WHICH HAVE HELD COMBUSTIBLES, ob-
tainable from American Welding Society, 550 N.W.
LeJeune Rd, Miami, FL 33126
8. NFPA Standard 51, OXYGEN-FUEL GAS SYSTEMS
FOR WELDING, CUTTING AND ALLIED PRO-
CESSES, obtainable from the National Fire Protection
Association, Batterymarch Park, Quincy, MA 02269
9. NFPA Standard 70, NATIONAL ELECTRICAL CODE,
obtainable from the National Fire Protection Associa-
tion, Batterymarch Park, Quincy, MA 02269
10. NFPAStandard 51B, CUTTINGAND WELDING PRO-
CESSES, obtainable from the National Fire Protection
Association, Batterymarch Park, Quincy, MA 02269
11. CGA Pamphlet P-1, SAFE HANDLING OF COM-
PRESSED GASES IN CYLINDERS, obtainable from the
Compressed Gas Association, 1235 Jefferson Davis
Highway, Suite 501, Arlington, VA22202
12. CSAStandard W117.2, CODE FOR SAFETY IN WELD-
ING AND CUTTING, obtainable from the Canadian
Standards Association, Standards Sales, 178 Rexdale
Boulevard, Rexdale, Ontario, Canada M9W 1R3
13. NWSA booklet, WELDING SAFETY BIBLIOGRAPHY
obtainable from the National Welding Supply Associa-
tion, 1900 Arch Street, Philadelphia, PA 19103
14. American WeldingSociety StandardAWSF4.1, RECOM-
MENDED SAFE PRACTICES FOR THE PREPARA-
TION FOR WELDINGAND CUTTING OF CONTAIN-
ERSAND PIPING THAT HAVE HELD HAZARDOUS
SUBSTANCES, obtainable from theAmerican Welding
Society, 550 N.W. LeJeune Rd, Miami, FL 33126
15. ANSI Standard Z88.2, PRACTICE FOR RESPIRATORY
PROTECTION, obtainable from American National
Standards Institute, 1430 Broadway, New York, NY
10018
1.04 Note, Attention et
Avertissement
Dans ce manuel, les mots “note,” “attention,” et
“avertissement” sont utilisés pour mettre en relief des
informations à caractère important. Ces mises en relief
sont classifiées comme suit :
NOTE
Toute opération, procédure ou renseignement
général sur lequel il importe d’insister davantage
ou qui contribue à l’efficacité de fonctionnement
du système.
ATTENTION
Toute procédure pouvant résulter
l’endommagement du matériel en cas de non-
respect de la procédure en question.
AVERTISSEMENT
Toute procédure pouvant provoquer des blessures
de l’opérateur ou des autres personnes se trouvant
dans la zone de travail en cas de non-respect de la
procédure en question.
1.05 Precautions De Securite
Importantes
AVERTISSEMENTS
L’OPÉRATION ET LA MAINTENANCE DU
MATÉRIEL DE SOUDAGE À L’ARC AU JET
DE PLASMA PEUVENT PRÉSENTER DES
RISQUES ET DES DANGERS DE SANTÉ.
Coupantàl’arc au jetdeplasmaproduitde l’énergie
électrique haute tension et des émissions
magnétique qui peuvent interférer la fonction
propre d’un “pacemaker” cardiaque, les appareils
auditif, ou autre matériel de santé electronique.
Ceux qui travail près d’une application à l’arc au
jet de plasma devrait consulter leur membre
professionel de médication et le manufacturier de
matériel de santé pour déterminer s’il existe des
risques de santé.
Il faut communiquer aux opérateurs et au person-
nel TOUS les dangers possibles. Afin d’éviter les
blessures possibles, lisez, comprenez et suivez tous
lesavertissements, toutes les précautionsdesécurité
et toutes les consignes avant d’utiliser le matériel.
Composez le + 603-298-5711 ou votre distributeur
local si vous avez des questions.
FUMÉE et GAZ
La fumée et les gaz produits par le procédé de jet de
plasma peuvent présenter des risques et des dangers de
santé.

GENERAL INFORMATION 1-4 Date: November 15, 2001
• Eloignez toute fumée et gaz de votre zone de respira-
tion. Gardez votre tête hors de la plume de fumée
provenant du chalumeau.
• Utilisez un appareil respiratoire à alimentation en air
sil’aérationfournienepermetpas d’éliminer la fumée
et les gaz.
• Les sortes de gaz et de fumée provenant de l’arc de
plasma dépendent du genre de métal utilisé, des
revêtements se trouvant sur le métal et des différents
procédés. Vous devez prendre soin lorsque vous
coupez ou soudez tout métal pouvant contenir un ou
plusieurs des éléments suivants:
antimoine cadmium mercure
argent chrome nickel
arsenic cobalt plomb
baryum cuivre sélénium
béryllium manganèse vanadium
• Lisez toujours les fiches de données sur la sécurité
des matières (sigle américain “MSDS”); celles-ci
devraient être fournies avec le matériel que vous
utilisez. Les MSDS contiennent des renseignements
quant à la quantité et la nature de la fumée et des gaz
pouvant poser des dangers de santé.
• Pour des informations sur la manière de tester la
fumée et les gaz de votre lieu de travail, consultez
l’article 1 et les documents cités à la page 5.
• Utilisez un équipement spécial tel que des tables de
coupe à débit d’eau ou à courant descendant pour
capter la fumée et les gaz.
• N’utilisez pas le chalumeau au jet de plasma dans une
zone où se trouvent des matières ou des gaz combus-
tibles ou explosifs.
• Le phosgène, un gaz toxique, est généré par la fumée
provenant des solvants et des produits de nettoyage
chlorés. Eliminez toute source de telle fumée.
• Ce produit, dans le procéder de soudage et de coupe,
produit de la fumée ou des gaz pouvant contenir des
éléments reconnu dans L’état de la Californie, qui
peuvent causer des défauts de naissance et le cancer.
(La sécurité de santé en Californie et la code sécurité
Sec. 25249.5 et seq.)
CHOC ELECTRIQUE
Les chocs électriques peuvent blesser ou même tuer. Le
procédé au jet de plasma requiert et produit de l’énergie
électrique haute tension. Cette énergie électrique peut
produiredes chocs graves, voire mortels,pourl’opérateur
et les autres personnes sur le lieu de travail.
• Netouchezjamaisune pièce “sous tension” ou “vive”;
portez des gants et des vêtements secs. Isolez-vous
de la pièce de travail ou des autres parties du circuit
de soudage.
• Réparez ou remplacez toute pièce usée ou
endommagée.
• Prenez des soins particuliers lorsque la zone de tra-
vail est humide ou moite.
• Montez et maintenez le matériel conformément au
Code électrique national des Etats-Unis. (Voir la page
5, article 9.)
• Débranchez l’alimentation électrique avant tout tra-
vail d’entretien ou de réparation.
• Lisez et respectez toutes les consignes du Manuel de
consignes.
INCENDIE ET EXPLOSION
Lesincendies et les explosionspeuventrésulter desscories
chaudes, des étincelles ou de l’arc de plasma. Le procédé
à l’arc de plasma produit du métal, des étincelles, des
scories chaudes pouvant mettre le feu aux matières com-
bustibles ou provoquer l’explosion de fumées
inflammables.
• Soyez certain qu’aucune matière combustible ou in-
flammable ne se trouve sur le lieu de travail. Protégez
toute telle matière qu’il est impossible de retirer de la
zone de travail.
• Procurez une bonne aération de toutes les fumées
inflammables ou explosives.
• Ne coupez pas et ne soudez pas les conteneurs ayant
pu renfermer des matières combustibles.
• Prévoyezune veilled’incendielorsde tout travail dans
une zone présentant des dangers d’incendie.
• Le gas hydrogène peut se former ou s’accumuler sous
les pièces de travail en aluminium lorsqu’elles sont
coupées sous l’eau ou sur une table d’eau. NE PAS
couper les alliages en aluminium sous l’eau ou sur
une table d’eau à moins que le gas hydrogène peut
s’échapperousedissiper. Legas hydrogèneaccumulé
explosera si enflammé.
RAYONS D’ARC DE PLASMA
Les rayons provenant de l’arc de plasma peuvent blesser
vos yeux et brûler votre peau. Le procédé à l’arc de
plasma produit une lumière infra-rouge et des rayons

Date: November 15, 2001 1-5 GENERAL INFORMATION
ultra-violets très forts. Ces rayons d’arc nuiront à vos
yeux et brûleront votre peau si vous ne vous protégez
pas correctement.
• Pour protéger vos yeux, portez toujours un casque ou
un écran de soudeur. Portez toujours des lunettes de
sécurité munies de parois latérales ou des lunettes de
protection ou une autre sorte de protection oculaire.
• Portezdesgants de soudeur et un vêtement protecteur
approprié pour protéger votre peau contre les
étincelles et les rayons de l’arc.
• Maintenez votre casque et vos lunettes de protection
en bon état. Remplacez toute lentille sale ou
comportant fissure ou rognure.
• Protégez les autres personnes se trouvant sur la zone
de travail contre les rayons de l’arc en fournissant des
cabines ou des écrans de protection.
• Utilisez la nuance de lentille qui est suggèrée dans le
recommendation qui suivent ANSI/ASC Z49.1:
Nuance Minimum Nuance Suggerée
Courant Arc Protective Numéro Numéro
Moins de 300* 8 9
300 - 400* 9 12
400 - 800* 10 14
*Ces valeurs s’appliquent ou l’arcactuel est observé
clairement. L’experience a démontrer que les filtres
moins foncés peuvent être utilisés quand l’arc est
caché par moiceau de travail.
BRUIT
Le bruit peut provoquer une perte permanente de l’ouïe.
Les procédés de soudage à l’arc de plasma peuvent
provoquer des niveaux sonores supérieurs aux limites
normalement acceptables. Vous dú4ez vous protéger les
oreilles contre les bruits forts afin d’éviter une perte
permanente de l’ouïe.
• Pour protéger votre ouïe contre les bruits forts, portez
des tampons protecteurs et/ou des protections
auriculaires. Protégezégalement les autres personnes
se trouvant sur le lieu de travail.
• Il faut mesurer les niveaux sonores afin d’assurer que
les décibels (le bruit) ne dépassent pas les niveaux
sûrs.
• Pour des renseignements sur la manière de tester le
bruit, consultez l’article 1, page 5.
1.06 Documents De Reference
Consultez les normes suivantes ou les révisions les plus
récentes ayant été faites à celles-ci pour de plus amples
renseignements :
1. OSHA, NORMES DE SÉCURITÉ DU TRAVAILET DE
PROTECTION DE LA SANTÉ, 29CFR 1910,
disponible auprès du Superintendent of Documents,
U.S. Government Printing Office, Washington, D.C.
20402
2. Norme ANSI Z49.1, LA SÉCURITÉ DES
OPÉRATIONS DE COUPE ET DE SOUDAGE,
disponible auprès de la Société Américaine de
Soudage (American Welding Society), 550 N.W.
LeJeune Rd., Miami, FL 33126
3. NIOSH, LA SÉCURITÉ ET LA SANTÉ LORS DES
OPÉRATIONS DE COUPE ET DE SOUDAGE À
L’ARC ET AU GAZ, disponible auprès du Superin-
tendent of Documents, U.S. Government Printing
Office, Washington, D.C. 20402
4. Norme ANSI Z87.1, PRATIQUES SURES POUR LA
PROTECTION DES YEUX ET DU VISAGEAU TRA-
VAIL ET DANS LES ECOLES, disponible de l’Institut
Américain des Normes Nationales (American Na-
tionalStandardsInstitute), 1430 Broadway, New York,
NY 10018
5. Norme ANSI Z41.1, NORMES POUR LES
CHAUSSURES PROTECTRICES, disponible auprès
de l’American National Standards Institute, 1430
Broadway, New York, NY 10018
6. NormeANSI Z49.2, PRÉVENTION DES INCENDIES
LORS DE L’EMPLOI DE PROCÉDÉS DE COUPE ET
DE SOUDAGE, disponible auprès de l’American Na-
tional Standards Institute, 1430 Broadway, NewYork,
NY 10018
7. Norme A6.0 de l’AssociationAméricaine du Soudage
(AWS), LE SOUDAGE ET LA COUPE DE
CONTENEURSAYANTRENFERMÉDES PRODUITS
COMBUSTIBLES, disponible auprès de la American
Welding Society, 550 N.W. LeJeune Rd., Miami, FL
33126
8. Norme 51 de l’Association Américaine pour la Pro-
tection contre les Incendies (NFPA), LES SYSTEMES
À GAZ AVEC ALIMENTATION EN OXYGENE
POUR LE SOUDAGE, LA COUPE ET LES
PROCÉDÉS ASSOCIÉS, disponible auprès de la Na-
tional Fire Protection Association, Batterymarch Park,
Quincy, MA 02269

GENERAL INFORMATION 1-6 Date: November 15, 2001
9. Norme 70 de la NFPA, CODE ELECTRIQUE NA-
TIONAL, disponible auprès de la National Fire Pro-
tectionAssociation,Batterymarch Park, Quincy,MA
02269
10.Norme 51B de la NFPA, LES PROCÉDÉS DE
COUPE ET DE SOUDAGE, disponible auprès de la
National Fire Protection Association, Batterymarch
Park, Quincy, MA 02269
11. Brochure GCA P-1, LA MANIPULATION SANS
RISQUE DES GAZ COMPRIMÉS EN CYLINDRES,
disponible auprès de l’Association des Gaz
Comprimés (Compressed Gas Association), 1235
Jefferson Davis Highway, Suite 501, Arlington, VA
22202
12. Norme CSA W117.2, CODE DE SÉCURITÉ POUR
LE SOUDAGE ET LA COUPE, disponible auprès
de l’Association des Normes Canadiennes, Stan-
dards Sales, 178 Rexdale Boulevard, Rexdale,
Ontario, Canada, M9W 1R3
13.Livret NWSA, BIBLIOGRAPHIE SUR LA
SÉCURITÉ DU SOUDAGE, disponible auprès de
l’Association Nationale de Fournitures de Soudage
(National Welding Supply Association), 1900 Arch
Street, Philadelphia, PA 19103
14. Norme AWSF4.1 de l’Association Américaine de
Soudage, RECOMMANDATIONS DE PRATIQUES
SURES POUR LAPRÉPARATION ÀLACOUPE ET
AU SOUDAGE DE CONTENEURS ET TUYAUX
AYANT RENFERMÉ DES PRODUITS
DANGEREUX , disponible auprès de la American
Welding Society, 550 N.W. LeJeune Rd., Miami, FL
33126
15. NormeANSIZ88.2, PRATIQUESDE PROTECTION
RESPIRATOIRE, disponible auprès de l’American
National Standards Institute, 1430 Broadway, New
York, NY 10018

Date: November 15, 2001 1-7 GENERAL INFORMATION
1.07 Declaration of Conformity
Manufacturer: Thermal Dynamics Corporation
Address: 82 Benning Street
West Lebanon, New Hampshire 03784
USA
The equipment described in this manual conforms to all applicable aspects and regulations of the ‘Low Voltage Directive’
(European Council Directive 73/23/EEC as amended by Council Directive 93/68/EEC) and to the National legislation for
the enforcement of this Directive.
Serialnumbers areunique with each individual pieceofequipment and details description, parts used to manufactureaunit
and date of manufacture.
National Standard and Technical Specifications
The product is designed and manufactured to a number of standards and technical requirements. Among them are:
* CSA(Canadian StandardsAssociation) standard C22.2 number 60 forArc welding equipment.
* UL(Underwriters Laboratory) rating 94VO flammability testing for all printed-circuit boards used.
* ISO/IEC 60974-1 (BS 638-PT10) (EN 60 974-1) (EN50192) (EN50078) applicable to plasma cutting equipment and associ-
ated accessories.
* Extensive product design verification is conducted at the manufacturing facility as part of the routine design and manufac-
turing process. This is to ensure the product is safe, when used according to instructions in this manual and related
industry standards, and performs as specified. Rigorous testing is incorporated into the manufacturing process to ensure
the manufactured product meets or exceeds all design specifications.
Thermal Dynamics has been manufacturing products for more than 30 years, and will continue to achieve excellence in our
area of manufacture.
Manufacturers responsible representative: Giorgio Bassi
Managing Director
Thermal Dynamics Europe
Via rio Fabbiani 8A
40067 Rastignano (BO)
Italy

GENERAL INFORMATION 1-8 Date: November 15, 2001
1.08 Statement of Warranty
LIMITED WARRANTY: Thermal Dynamics®Corporation (hereinafter “Thermal”) warrants that its products will be free of defects in
workmanship or material. Should any failure to conform to this warranty appear within the time period applicable to the Thermal
products as stated below, Thermal shall, upon notification thereof and substantiation that the product has been stored, installed, operated,
and maintained in accordance with Thermal’s specifications, instructions, recommendations and recognized standard industry practice,
and not subject to misuse, repair, neglect, alteration, or accident, correct such defects by suitable repair or replacement, at Thermal’s sole
option, of any components or parts of the product determined by Thermal to be defective.
THIS WARRANTY IS EXCLUSIVE AND IS IN LIEU OF ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A
PARTICULAR PURPOSE.
LIMITATION OF LIABILITY: Thermal shall not under any circumstances be liable for special or consequential damages, such as, but
not limited to, damage or loss of purchased or replacement goods, or claims of customers of distributor (hereinafter “Purchaser”) for
service interruption. The remedies of the Purchaser set forth herein are exclusive and the liability of Thermal with respect to any
contract, or anything done in connection therewith such as the performance or breach thereof, or from the manufacture, sale, delivery,
resale, or use of any goods covered by or furnished by Thermal whether arising out of contract, negligence, strict tort, or under any
warranty, or otherwise, shall not, except as expressly provided herein, exceed the price of the goods upon which such liability is based.
THIS WARRANTY BECOMES INVALID IF REPLACEMENT PARTS OR ACCESSORIES ARE USED WHICH MAY IMPAIR THE
SAFETY OR PERFORMANCE OF ANY THERMAL PRODUCT.
THIS WARRANTY IS INVALID IF THE PRODUCT IS SOLD BY NON-AUTHORIZED PERSONS.
The limited warranty periods for Thermal products shall be as follows (with the exception of XL Plus Series, CutMaster Series , Cougar
and DRAG-GUN): A maximum of three (3) years from date of sale to an authorized distributor and a maximum of two (2) years from
date of sale by such distributor to the Purchaser, and with the further limitations on such two (2) year period (see chart below).
The limited warranty period for XL Plus Series and CutMaster Series shall be as follows: A maximum of four (4) years from date
of sale to an authorized distributor and a maximum of three (3) years from date of sale by such distributor to the Purchaser, and
with the further limitations on such three (3) year period (see chart below).
The limited warranty period for Cougar and DRAG-GUN shall be as follows: Amaximum of two (2) years from date of sale to an
authorized distributor and a maximum of one (1) year from date of sale by such distributor to the Purchaser, and with the further
limitations on such two (2) year period (see chart below).
Parts
XL Plus & Parts Parts
PAK Units, Power Supplies CutMaster Series Cougar/Drag-Gun All Others Labor
Main Power Magnetics 3 Years 1 Year 2 Years 1 Year
Original Main Power Rectifier 3 Years 1 Year 2 Years 1 Year
Control PC Board 3 Years 1 Year 2 Years 1 Year
All Other Circuits And Components Including, 1 Year 1 Year 1 Year 1 Year
But Not Limited To, Starting Circuit,
Contactors, Relays, Solenoids, Pumps,
Power Switching Semi-Conductors
Consoles, Control Equipment, Heat 1 Year 1 Year 1 Year
Exchanges, And Accessory Equipment
Torch And Leads
Maximizer 300 Torch 1 Year 1 Year
SureLok Torches 1 Year 1 Year 1 Year
All Other Torches 180 Days 180 Days 180 Days 180 Days
Repair/Replacement Parts 90 Days 90 Days 90 Days None
Warranty repairs or replacement claims under this limited warranty must be submitted by an authorized Thermal Dynamics® repair
facility within thirty (30) days of the repair. No transportation costs of any kind will be paid under this warranty. Transportation charges
to send products to an authorized warranty repair facility shall be the responsibility of the customer. All returned goods shall be at the
customer’s risk and expense. This warranty supersedes all previous Thermal warranties.
Effective: November 15, 2001

Manual 0-2747 2-1 INTRODUCTION
2.03 Service Responsibilities
The service technician should be familiar with the equip-
ment and its capabilities. The technician should be pre-
paredto recommendarrangements of components which
will provide the most efficient layout, utilizing the equip-
ment to its best possible advantage.
Maintenance work should be accomplished in a timely
manner. If problems are encountered, or the equipment
does not function as specified, contact the Technical Ser-
vices Department for assistance.
SECTION 2:
INTRODUCTION
2.01 Scope Of Manual
This Manual provides Service Instructions for Thermal
Dynamics PAK Master®75XL PLUS Plasma Power Sup-
ply.
Refer to Operating Manual 0-2746 for individual operat-
ing procedures. Information in this edition is therefore
particularlyapplicable to the Troubleshootingand Repair
of the equipment, and is intended for use by properly-
trained Service Technicians familiar with this equipment.
ReadthisManualandtheOperatingManual0-2746,thor-
oughly. Acompleteunderstandingofthe capabilities and
functions of the equipment will assure obtaining the per-
formance for which it was designed.
2.02 General Service Philosophy
Several key points are essential to properly support the
application and operation of this equipment.
A. Application
The equipment should satisfy the customer’s require-
ments as supplied and as described in Section 3 of this
manual. Be sure to confirm that the equipment is capable
of the application desired.
B. Modifications
No physical or electrical modifications other than selec-
tion of standard options and accessories are to be made
to this equipment.
C. Customer/Operator Responsibilities
It is the customer/operator's responsibility to maintain
the equipment and peripheral Accessories provided by
ThermalDynamicsingoodoperating order in accordance
with the procedures outlined in the Operating Manual,
and to protect the equipment from accidental or mali-
cious damage.
D. Repair Restrictions
The electronics consists of Printed Circuit BoardAssem-
blies which must be carefully handled, and must be re-
placed as units. No replacement of printed circuit sol-
der-mounted components is allowed except as noted in
this manual.
Printed Circuit BoardAssemblies to be returned must be
properly packaged in protective material and returned
intact per normal procedures.

INTRODUCTION 2-2 Manual 0-2747

Manual 0-2747 3-1 DESCRIPTION
SECTION 3:
DESCRIPTION
3.01 Scope
The purpose of the information in this section is:
• To familiarize the service technician with the capa-
bilities and limitations of the equipment
• To provide an overall understanding which will al-
low the technician, in turn, to properly train
customer's operating personnel.
3.02 General Description of System
The 75XL PLUS System includes a power supply and
torch & leads. The power supply provides 60 amp maxi-
mum output and includes all control circuitry, electrical
and gas inputs and outputs, pilot circuitry, torch leads
receptacleand a work cable with clamp. 208/230V single-
phase units include 50 amp input cable and plug.
NOTE
The power supply can be ordered in various con-
figurations with various options factory installed.
A-02462
Torch and Leads
Work Cable and Clamp
XL PLUS Power Supply
The torch provides a maximum 3/4 inch (19.1 mm) cut
capacity. The hand torch is available with various head
configurations and a machine torch in a 180° head con-
figuration. Torch leads are available in various lengths
with fittings for simple installation. Spare Parts Kits are
available which provide an assortment of replacement
torch parts.
NOTE
Refer to Section 3.04 for list of power supply op-
tions and accessories.
3.03 Specifications/Design Features
A. Power SupplyTechnical Specifications
The following specifications apply to the Power Supply
only:
1. Front Panel Controls
ON/OFF Switch, RUN/SET/LATCH Switch and
Output Current Control (A)
2. Front Panel Indicators
AC , TEMP , GAS , DC
3. Rear Panel
InputPowerCable Strain Relief*, Gas Connection, Gas
Regulator/FilterAssembly
*208/230V single-phase units also include 50 amp input
cable and plug.
4. Input Power
Can be configured for the following input power:
208/230/240 VAC (±10%), 50/60 Hz, Single or Three-
Phase
380/415 VAC (±10%), 50/60 Hz, Three-Phase
460 VAC (±10%), 50/60 Hz, Single or Three-Phase
5. Output Power
Continuously variable from 15 to 60Amps maximum
6. Duty Cycle (see NOTE)
NOTE
The duty cycle will be reduced if the primary in-
put voltage (AC) is low or the DC voltage is higher
than shown in the chart.
Ambient
Tem
p
erature 104° F
(40° C) 104° F (40° C)
Duty Cycle 65% 100%
Current 60 Amps 50 Amps
DC Voltage 104 vdc 104 vdc
Power Supply Duty Cycle
7. Cut Capacity (Mild Steel)
3/4 inch (19.1 mm); 1 inch (25.4 mm) severance
8. Pilot Circuitry
Capacitive Discharge (CD), Pulsed DC

DESCRIPTION 3-2 Manual 0-2747
9. Weight
64 lbs (29 kg) w/work lead
71 lbs (32 kg) w/work lead and 25' Torch & Lead
10. Overall Dimensions
19" (482 mm) High x 13" (330 mm) Wide x 24.8"
(630 mm) Long
Overall dimensions are with Handle, Lead Wrap
Bracket,andGasRegulator/FilterAssembly installed.
B. Gas Regulator/Filter Assembly
Specifications
The following specifications apply to the Gas Regulator/
Filter Assembly only:
1. Gas regulator maximum gauge pressure
160 psi (11 bar)
2. Maximum input gas pressure
125 psi (8.6 bar)
3. Filter
Coalescent type filter
3.04 Power Supply Options and
Accessories
The following accessories are available for this power
supply. Refer to Section 6, Parts Lists, for catalog num-
bers and ordering information.
A. Single-Stage Filter Kit
A Single Stage In-Line Air Filter for use with com-
pressed air shop systems. Filters moisture and par-
ticulate matter from the air stream to at least 0.85 mi-
crons.
B. Two Stage Air Line Filter
ATwo Stage In-Line Air Filter for use on compressed
airshopsystems. Filters moistureand particulate mat-
ter from the air stream to at least 5.0 microns.
C. High Pressure Regulators
High pressure regulators are available for air and ni-
trogen. The regulators are used to set the proper pres-
sure for the type gas being used.
D. Multi-Purpose Cart
Rugged steel cart on easy-rolling rear wheels and
front-mounted swivel casters. Provides maximum
mobility for the power supply and can also serve as a
display cart. Top shelf is 12 " (305 mm) x 20 (508 mm).
Steel handle is 30" (762 mm) high.
E. 575VTransformer
This step-down transformer allows the power sup-
ply to operate with 575 VAC three-phase input power.
F. Computer Control Cable (CNC)
This accessory is for use with PCM Torches only.
This interface cable is available in two lengths, 25 ft
(7.6 m) and 50 ft (15.2 m). The cable is used to inter-
face the power supply with an auxiliary control de-
vice to provide OK-To-Move and ON/OFF signals.
G. Cutting Guide Kit
Easy add-on attachments to allow for straight line,
circle, or bevel cutting.
H. Standoff Cutting Guide
Simple, push-on guide attachment to allow for torch
dragging without risk of touching tip.

Manual 0-2747 4-1 TROUBLESHOOTING
Section 4:
TROUBLESHOOTING
4.01 Introduction
This section provides service diagnostics for the Pak
Master 75XL PLUS Power Supply, allowing the Techni-
cian to isolate any faulty Subassemblies. Refer to Section
5, Repairs & Replacement Procedures, for parts replace-
ment instructions.
Under no circumstances are field repairs to be attempted
on Printed Circuit Boards or other Subassemblies of this
unit. Evidence of unauthorized repairs will void the fac-
tory warranty.
NOTE
The troubleshooting contained in this manual is
for the Power Supply only. Troubleshooting other
partsof the system is coveredin the separate manu-
als for those products.
4.02 Periodic Inspection &
Procedures
This subsection describes inspection procedures which
should be performed at periodic intervals as required.
A. Physical Inspection
Check that all cable connections are secure.
B. Cleaning
UnitshouldbecleanedperAppendix 11,Maintenance
Schedule.
4.03 Common Operating Problems
WARNINGS
Disconnect primary power at the source before dis-
assembling the power supply, torch, or torch leads.
Frequently review the Important Safety Precau-
tions (Section 1). Be sure the operator is equipped
with proper gloves, clothing, eye and ear protec-
tion.Makesurenopart of the operator’s body comes
into contact with the workpiece while the torch is
activated.
Sparks from the cutting process can cause damage
tocoated, painted,andother surfaces such as glass,
plastic and metal.
Handletorchleads with care and protectthem from
damage.
A. Piloting
Piloting is harder on parts life than actual cutting be-
cause the pilot arc is directed from the electrode to
thetip rather than to a workpiece. Whenever possible,
avoid excessive pilot arc time to improve parts life.
B. Torch Standoff
Improper standoff (the distance between the torch tip
and workpiece) can adversely affect tip life as well as
shield cup life. Standoff may also significantly affect
the bevel angle. Reducing standoff generally results
in a more square cut.
C. Edge Starting
For edge starts, hold the torch perpendicular to the
workpiece with the front of the torch tip at the edge
of the workpiece, not touching, at the point where the
cut is to start. When starting at the edge of the plate,
do not pause at the edge and force the arc to “reach”
for the edge of the metal. Establish the cutting arc as
quickly as possible.
D. Direction of Cut
The plasma gas stream swirls as it leaves the torch.
The purpose of the swirl is to maintain a smooth col-
umn of gas. The swirl effect results in one side of a
cut being more square than the other. Viewed along
the direction of travel, the right side of the cut is more
square than the left.
E. Dross
When dross is present on carbon steel, it is commonly
referred to as either “high speed, slow speed, or top
dross”. Dross present on top of the plate is normally
caused by too great a torch to plate distance. "Top
dross" is normally very easy to remove and can often
bewipedoff with a weldingglove. "Slowspeeddross"
is normally present on the bottom edge of the plate.
It can vary from a light to heavy bead, but does not
adhere tightly to the cut edge, and can be easily
scraped off. "High speed dross" usually forms a nar-
row bead along the bottom of the cut edge and is very
difficultto remove. Whencutting a troublesomesteel,
it is sometimes useful to reduce the cutting speed to
produce "slow speed dross". Any resultant cleanup
can be accomplished by scraping, not grinding.

TROUBLESHOOTING 4-2 Manual 0-2747
F. Common Cutting Faults
1. Insufficient Penetration
a. Cutting speed too fast
b. Torch tilted too much
c. Metal too thick
d. Worn torch parts
e. Cutting current too low
f. Non-Genuine Thermal Dynamics parts used
2. Main Arc Extinguishes
a. Cutting speed too slow
b. Torch standoff too high from workpiece
c. Cutting current too high
d. Work cable disconnected
e. Worn torch parts
f. Non-Genuine Thermal Dynamics parts used
3. Excessive Dross Formation
a. Cutting speed too slow
b. Torch standoff too high from workpiece
c. Worn torch parts
d. Improper cutting current
e. Non-Genuine Thermal Dynamics parts used
4. Short Torch Parts Life
a. Moisture in air source
b. Exceeding system capability (material too thick)
c. Excessive pilot arc time
d. Air flow too low (incorrect pressure)
e. Improperly assembled torch
f. Incorrect torch parts for the operation
g. Non-Genuine Thermal Dynamics parts used
4.04 Troubleshooting Guide -
General Information
WARNING
There are extremely dangerous voltage and power
levels present inside this unit. Do not attempt to
diagnose or repair unless you have had training in
power electronics measurement and troubleshoot-
ing techniques.
A. Troubleshooting and Repair
Troubleshooting and repair of this unit should be under-
takenonlyby those familiar with high voltage high power
electronic equipment.
B. AdvancedTroubleshooting
For basic troubleshooting and parts replacement proce-
dures refer to Pak Master 75XL PLUS Operating Manual
0-2746.
The advanced troubleshooting covered in this Service
ManualrequiresPowerSupplydisassembly and live mea-
surements. It is helpful for solving many of the common
problems that can arise with the Pak Master 75XL PLUS
Power Supply.
If major complex subassemblies are faulty, the faulty sub-
assembly must be returned for repair.
NOTE
Follow all instructions as listed and complete each
in the order presented.
Subsection4.09includesspecifictestprocedures and LED
status identification tables. The subsection is referenced
by the troubleshooting guide for the specific test to be
performed.
The troubleshooting guide has sub-sections as follows:
Section 4.05 - Circuit Fault Isolation
Section 4.06 - Main Input and Internal Power Prob-
lems
Section 4.07 - Pilot Arc Problems
Section 4.08 - Main Arc Problems
Section 4.09 - Test Procedures