Thermadyne Thermal Dynamics PAK MASTER 50XL User manual

Manual No. 0-2587
August 11, 1999
PAK MASTER
®
50XL
Air Plasma Cutting
Power Supply
Service Manual
A-01324

WARNING
WARNING
Read and understand this entire Service Manual and your
employer’s safety practices before installing, operating, or
servicing the equipment.
While the information contained in this Service Manual repre-
sents our best judgement, Thermal Dynamics Corporation
assumes no liability for its use.
Pak Master®50XL Air Plasma Cutting Power Supply
Service Manual Number 0-2587
Published by:
Thermal Dynamics Corporation
Industrial Park No. 2
West Lebanon, New Hampshire, USA 03784
[phone]
Copyright 1997 by
Thermal Dynamics Corporation
All rights reserved.
Reproduction of this work, in whole or in part, without written
permission of the publisher is prohibited.
The publisher does not assume and hereby disclaims any liabil-
ity to any party for any loss or damage caused by any error or
omission in the Pak Master®50XL Air Plasma Cutting Power
Supply Service Manual, whether such error results from negli-
gence, accident, or any other cause.
Printed in the United States of America
August 11, 1999

TABLE OF CONTENTS
SECTION 1:
GENERAL INFORMATION .................................................................................................. 1
1.01 Notes, Cautions andWarnings ...................................................................... 1
1.02 Important Safety Precautions ........................................................................ 1
1.03 Publications ................................................................................................... 2
1.04 Note, Attention et Avertissement ................................................................... 3
1.05 Precautions De Securite Importantes ............................................................ 3
1.06 Documents De Reference ............................................................................. 5
1.07 Declaration of Conformity .............................................................................. 6
1.08 Statement ofWarranty ................................................................................... 7
SECTION 2:
INTRODUCTION ................................................................................................................. 9
2.01 Scope Of Manual........................................................................................... 9
2.02 General Service Philosophy .......................................................................... 9
2.03 Service Responsibilities................................................................................. 9
SECTION 3:
DESCRIPTION .................................................................................................................. 11
3.01 Scope .......................................................................................................... 11
3.02 General Description..................................................................................... 11
3.03 Specifications/Design Features ................................................................... 11
3.04 Power Supply Options and Accessories ...................................................... 12
SECTION 4:
SERVICETROUBLESHOOTING DIAGNOSTICS ............................................................. 13
4.01 Introduction.................................................................................................. 13
4.02 Periodic Inspection & Procedures................................................................ 13
4.03 Common Operating Problems ..................................................................... 13
4.04 Troubleshooting Guide - General Information............................................... 14
4.05 Circuit Fault Isolation ................................................................................... 15
4.06 Main Input and Internal Power Problems ..................................................... 16
4.07 Pilot Arc Problems ....................................................................................... 19
4.08 Main Arc Problems ...................................................................................... 20
4.09 Test Procedures........................................................................................... 20
SECTION 5:
REPAIRS & REPLACEMENT PROCEDURES................................................................... 29
5.01 Introduction.................................................................................................. 29
5.02 Anti-Static Handling Procedures .................................................................. 29
5.03 Parts Replacement - General Information.................................................... 29
5.04 Major External Parts Replacement .............................................................. 30
5.05 Access Panel Parts Replacement................................................................ 31
5.06 Front Panel Parts Replacement ................................................................... 31
5.07 Left Side Internal Component Parts Replacement ....................................... 32
5.08 Rear Panel Parts Replacement ................................................................... 34
5.09 Right Side Internal Component Parts Replacement..................................... 35

TABLE OF CONTENTS (continued)
SECTION 6:
PARTS LISTS.....................................................................................................................37
6.01 Introduction.................................................................................................. 37
6.02 Ordering Information.................................................................................... 37
6.03 Major External Replacement Parts List........................................................ 38
6.04 Access Panel Replacement Parts List ......................................................... 40
6.05 Front Panel Replacement Parts List............................................................. 42
6.06 Left Side Internal Component Replacement Parts List ................................ 44
6.07 Rear Panel Replacement Parts List ............................................................. 46
6.08 Right Side Internal Component Replacement Parts List .............................. 48
6.09 Options and Accessories............................................................................. 50
APPENDIX I: INPUT WIRING REQUIREMENTS ...................................................................... 51
APPENDIX II: SEQUENCE OF OPERATION (BLOCK DIAGRAM) ........................................... 52
APPENDIX III: POT/LED PC BOARD LAYOUT.......................................................................... 53
APPENDIX IV: LOGIC PC BOARD LAYOUT ............................................................................. 54
APPENDIXV: GATE DRIVE PC BOARD LAYOUT .................................................................... 56
APPENDIXVI: PILOT OUTPUT PC BOARD LAYOUT............................................................... 58
APPENDIX VII: CD PC BOARD LAYOUT .................................................................................. 60
APPENDIXVIII: INPUT PC BOARD LAYOUT............................................................................ 61
APPENDIX IX: FET PC BOARD LAYOUT ................................................................................. 62
APPENDIX X: CAPACITOR PC BOARD LAYOUT ..................................................................... 64
APPENDIX XI: 36VAC CIRCUIT DIAGRAM............................................................................... 65
APPENDIX XII: SYSTEM SCHEMATIC ..................................................................................... 66

Date:6/22/99 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 theequipment. 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
on the 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 readtheMaterial SafetyData Sheets (MSDS)
that should be supplied with the material you are
using. These MSDSs will give you the information
regarding the kind and amount offumes and gases
that may be dangerous to your health.
• For information on how to test for fumes and gases
in your workplace, refer to item 1 in Subsection
1.03, Publications in this manual.
• Use special equipment, such as water or down draft
cutting tables, to capture fumes and gases.
• Do not use the plasma torch in an area where com-
bustibleor explosive gasesor materials arelocated.
• Phosgene, a toxic gas, is generated from the vapors
of chlorinated solvents and cleansers. Remove all
sources of these vapors.
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.”
•Weardrygloves andclothing. Insulate yourself from
the work piece or other parts of the welding cir-
cuit.
• Repair or replace all worn or damaged parts.
• Extra care must be taken when the workplace is
moist or damp.

GENERAL INFORMATION 2 Date 6/22/99
• Install and maintain equipment according to NEC
code, refer to item 9 in Subsection 1.03, Publica-
tions.
•Disconnect powersource before performingany ser-
vice 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 mate-
rial in the workplace. Any material that cannot be
removed must be protected.
• Ventilate all flammable or explosive vapors from
the workplace.
•Do not cutor weld oncontainers that mayhave held
combustibles.
• Providea fire watchwhen workingin an area where
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
Noisecan cause permanenthearing loss. Plasma arc pro-
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.
• Noise levels should be measured to be sure the 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
PlasmaArcRays caninjureyour eyesand burnyour skin.
The plasma arc process produces very bright ultra violet
and infra red light. These arc rays will damage your
eyesand burnyour skinif youarenotproperlyprotected.
• To protect your eyes, always wear a welding hel-
metor shield. Also always wear safetyglasses 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
* Thesevalues apply where theactual arc isclearly
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, SAFETY AND HEALTH STANDARDS,
29CFR 1910, obtainable from the Superintendent of
Documents, U.S. Government Printing Office, Wash-
ington, D.C. 20402
2. ANSI Standard Z49.1, SAFETY IN WELDING AND
CUTTING, obtainable from the American Welding
Society, 550 N.W. LeJeune Rd, Miami, FL 33126
3. NIOSH, SAFETY AND HEALTH IN ARC WELD-
INGAND GAS WELDING AND CUTTING, obtain-
able from the Superintendent of Documents, U.S.
GovernmentPrinting Office, Washington, D.C. 20402
4. ANSI Standard Z87.1, SAFE PRACTICES FOR OC-
CUPATIONAND EDUCATIONALEYEAND FACE
PROTECTION, obtainable from American National
Standards Institute, 1430 Broadway, New York, NY
10018
5. ANSI Standard Z41.1, STANDARD FOR MEN’S
SAFETY-TOE FOOTWEAR, obtainable from the
American National Standards Institute, 1430 Broad-
way, New York, NY 10018
6. ANSI Standard Z49.2, FIRE PREVENTION IN THE
USE OF CUTTING AND WELDING PROCESSES,
obtainable fromAmerican National Standards Insti-
tute, 1430 Broadway, New York, NY 10018
7. AWS Standard A6.0, WELDING AND CUTTING
CONTAINERS WHICH HAVE HELD COMBUS-
TIBLES, obtainable fromAmerican Welding Society,
550 N.W. LeJeune Rd, Miami, FL 33126

Date:6/22/99 3 GENERAL INFORMATION
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. NFPAStandard70,NATIONALELECTRICALCODE,
obtainable from the National Fire Protection Asso-
ciation, Batterymarch Park, Quincy, MA 02269
10. NFPA Standard 51B, CUTTING AND WELDING
PROCESSES, obtainable from the National Fire Pro-
tection 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, VA 22202
12. CSA Standard W117.2, CODE FOR SAFETY IN
WELDING AND CUTTING, obtainable from the Ca-
nadian Standards Association, Standards Sales, 178
Rexdale Boulevard, Rexdale, Ontario, Canada M9W
1R3
13. NWSA booklet, WELDING SAFETY BIBLIOGRA-
PHY obtainable from the National Welding Supply
Association, 1900Arch Street, Philadelphia, PA19103
14. American Welding Society StandardAWSF4.1, REC-
OMMENDED SAFE PRACTICES FOR THE PREPA-
RATION FOR WELDING AND CUTTING OF CON-
TAINERS AND PIPING THAT HAVE HELD
HAZARDOUS SUBSTANCES, obtainable from the
American Welding Society, 550 N.W. LeJeune Rd,
Miami, FL 33126
15. ANSI Standard Z88.2, PRACTICE FOR RESPIRA-
TORY 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.
Coupantà l’arcaujet deplasma produitdel’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 lesprécautionsdesécurité
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.
• Eloignez toute fumée et gaz de votre zone de respi-
ration. Gardez votre tête hors de la plume de fumée
provenant du chalumeau.
• Utilisez un appareil respiratoire à alimentation en
air si l’aération fournie ne permet pas d’éliminer la
fumée et les gaz.

GENERAL INFORMATION 4 Date 6/22/99
• Les sortes de gaz et de fumée provenant de l’arc de
plasma dépendent du genre de métal utilisé, des
revêtementsse trouvantsurle métalet 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
combustibles ou explosifs.
• Le phosgène, un gaz toxique, est généré par la fumée
provenantdessolvants et desproduitsde nettoyage
chlorés. Eliminez toute source de telle fumée.
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
produire des chocsgraves, voiremortels,pour l’opérateur
et les autres personnes sur le lieu de travail.
• Ne touchez jamais une pièce “sous tension” ou
“vive”; portez des gants et des vêtements secs.
Isolez-vous de la pièce de travail ou des autres par-
ties 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 etles explosions peuventrésulterdes scories
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.
• Necoupez pas etne soudez pasles conteneurs ayant
pu renfermer des matières combustibles.
• Prévoyez une veille d’incendie lors de 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’échapper ou se dissiper. Le gas hydrogène
accumulé explosera si enflammé.
RAYONS D’ARC DE PLASMA
Les rayons provenant de l’arc de plasma peuvent blesser
vosyeux etbrûler votrepeau.Le procédéàl’arcdeplasma
produit une lumière infra-rouge et des rayons ultra-vio-
lets 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
ouun écrande soudeur.Portez toujoursdes lunettes
de sécurité munies de parois latérales ou des lu-
nettes de protection ou une autre sorte de protec-
tion oculaire.
• Portez des gants 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 protec-
tion 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.

Date:6/22/99 5 GENERAL INFORMATION
• Utilisez la nuance de lentille qui est suggèrée dans
le recommendation qui suiventANSI/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 valeurss’appliquent ou l’arcactuelest 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 protégervotre ouïecontreles bruitsforts,portez
des tampons protecteurs et/ou des protections
auriculaires. Protégez également 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 TRAVAIL ET
DE PROTECTION DE LA SANTÉ, 29CFR 1910,
disponible auprès du Superintendent of Docu-
ments, U.S. Government Printing Office, Washing-
ton, 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 ETAU 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 VISAGE AU
TRAVAIL ET DANS LES ECOLES, disponible de
l’InstitutAméricain desNormes Nationales(Ameri-
can National Standards Institute), 1430 Broadway,
New York, NY 10018
5. Norme ANSI Z41.1, NORMES POUR LES
CHAUSSURESPROTECTRICES, disponibleauprès
de l’American National Standards Institute, 1430
Broadway, New York, NY 10018
6. Norme ANSI Z49.2, PRÉVENTION DES
INCENDIES LORS DE L’EMPLOI DE PROCÉDÉS
DE COUPE ET DE SOUDAGE, disponible auprès
de l’American National Standards Institute, 1430
Broadway, New York, NY 10018
7. Norme A6.0 de l’Association Américaine du
Soudage (AWS), LE SOUDAGE ET LACOUPE DE
CONTENEURS AYANT RENFERMÉ DES
PRODUITSCOMBUSTIBLES, disponible auprès de
laAmerican WeldingSociety, 550 N.W. LeJeuneRd.,
Miami, FL 33126
8. Norme 51 de l’AssociationAméricaine pour la Pro-
tectioncontreles Incendies (NFPA), LES SYSTEMES
À GAZ AVEC ALIMENTATION EN OXYGENE
POUR LE SOUDAGE, LA COUPE ET LES
PROCÉDÉS ASSOCIÉS, disponible auprès de la
National Fire ProtectionAssociation, Batterymarch
Park, Quincy, MA 02269
9. Norme 70 de la NFPA, CODE ELECTRIQUE NA-
TIONAL,disponible auprèsde la National FirePro-
tectionAssociation, BatterymarchPark, 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 CSAW117.2, 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.ivretNWSA, BIBLIOGRAPHIE SUR LASÉCURITÉ
DU SOUDAGE, disponible auprès de l’Association
Nationale de Fournitures de Soudage (National
Welding Supply Association), 1900 Arch Street,
Philadelphia, PA 19103

GENERAL INFORMATION 6 Date 6/22/99
14. Norme AWSF4.1 de l’AssociationAméricaine de
Soudage, RECOMMANDATIONS DE PRA-
TIQUES SURES POUR LAPRÉPARATIONÀLA
COUPE 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. Norme ANSI Z88.2, PRATIQUES DE PROTEC-
TION RESPIRATOIRE, disponible auprès de
l’American National Standards Institute, 1430
Broadway, New York, NY 10018

Date:6/22/99 7 GENERAL INFORMATION
1.07 Declaration of Conformity
Manufacturer: Thermal Dynamics Corporation
Address: Industrial Park #2
West Lebanon, New Hampshire 03784
USA
The equipment described in this manual conforms to all applicable aspects and regulations of the ‘Low Voltage Direc-
tive’ (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.
Serial numbers are unique with each individual piece of equipment and details description, parts used to manufacture
a unit 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
manufacturing 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: Steve Ward
Director of Operations
ThermadyneUK
ChorleyEngland

GENERAL INFORMATION 8Date 6/22/99
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, atThermal’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 liabilityis based.
THIS WARRANTY BECOMES INVALID IF REPLACEMENT PARTS OR ACCESSORIES ARE USED WHICH MAY IMPAIR THE
SAFETY OR PERFORMANCE OF ANY THERMALPRODUCT.
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 XLPlus Series, CutMaster 80XL, Cougar
and DRAG-GUN): Amaximum 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 XLPlus Series and CutMaster 80XLshall be as follows: Amaximum 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 Series & Parts Parts
PAK Units, Power Supplies CutMaster 80XL 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 Board3 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
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 May 6, 1999

Manual 0-2587 9 INTRODUCTION
2.03 Service Responsibilities
TheService Technician should be familiar with the equip-
ment and its capabilities. He should be prepared to rec-
ommend arrangements of components which will pro-
vide the most efficient layout, utilizing the equipment 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 Technical Services
Department at West Lebanon for assistance.
SECTION 2:
INTRODUCTION
2.01 Scope Of Manual
This Manual provides Service Instructions for Thermal
Dynamics PAK Master®50XLAir Plasma Power Supply.
Refer to Operating Manual (0-2586) for individual oper-
ating procedures. Information in this edition is therefore
particularlyapplicable to theTroubleshooting and Repair
of the equipment, and is intended for use by properly-
trained Service Technicians familiar with this equipment.
Read this Manual and the Operating Manual, 0-2586,
thoroughly. A complete understanding of the capabili-
ties and functions of the equipment will assure obtaining
the performance 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/operators’ responsibility to maintain
the equipment and peripheral Accessories provided by
ThermalDynamics ingood operating order inaccordance
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.
If to be returned, the replaced Printed Circuit Board As-
semblies must be properly packaged in protective mate-
rial and returned intact per normal procedures.

INTRODUCTION 10 Manual 0-2587

Manual 0-2587 11 DESCRIPTION
SECTION 3:
DESCRIPTION
3.01 Scope
The information in this Section has two purposes:
• 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
Thepower supplyprovides35amp maximumoutput and
includesall controlcircuitry, electrical and gasinputs and
outputs, pilot circuitry, torch leads receptacle and a work
cable with clamp. Machine torch systems also include a
remote hand ON/OFF pendant.
NOTE
The power supply can be ordered in various con-
figurations with various options factory installed.
Pak Master 50XL
Power Supply
PCH/M-28
Torch and Leads
Work Cable
With Clamp
A-01325
Figure 2-1 Pak Master 50XL Power Supply
The power supply is designed to work with the Model
PCH/M-28 Plasma Torches.
Torches will provide a maximum 1/2 inch (12.7 mm) cut
capacity. Hand torches are available in 70° and 90° con-
figurations. Machine torches are available only in Model
PCM-28 and include a rack and pinion mounting assem-
bly. Torch leads are available in 25 ft (7.6 m), or 50 ft (15.2
m) lengths with fittings for simple installation. The torch
includes a spare parts kit which provides 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 Switch and Output Cur-
rent Control
2. Front Panel LED Indicators
AC, TEMP, GAS, DC
3. Rear Panel
Input power cable strain relief, gas connection, Gas
Regulator/FilterAssembly
4. Input Power
Available for the following input power:
208/230/240 VAC (±10%), 50/60 Hz, Single or Three-
Phase
380/415VAC(±10%), 50/60Hz, Singleor Three-Phase
460 VAC (±10%), 50/60 Hz, Single or Three-Phase
5. Output Power
Continuously variable from 15 to 35Amps maximum
6. Duty Cycle
60% Duty Cycle @ 125V output with 60 Hz input
50% Duty Cycle @ 125V output with 50 Hz input
7. Cut Capacity
1/2 inch (12.7 mm); 3/4 inch (19 mm) severance
8. Pilot Circuitry
High Frequency (HF), Pulsed DC
9. Weight
65 lbs (29.5 kg)

DESCRIPTION 12 Manual 0-2587
10. Overall Dimensions
18.9" (480 mm) High x 13" (330 mm) Wide x 23.5" (597
mm) Long
Overall dimensions are with handle, lead wrap
bracket,and Gas Requlator/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 or 11.03 kPa)
2. Maximum input gas pressure
125 psi (8.6 BAR or 861 kPa)
3. Filter
Coalescent type filter
3.04 Power Supply Options and
Accessories
NOTE
Refer to Section 6, Parts Lists, for part numbers
and ordering information.
The following are accessories that are available for this
power supply:
A. Primary Input Power Cable
An optional 220V, single phase, six foot primary in-
put power cable with plug.
B. Two Stage Air Line Filter
An optional two stage air line filter is available. The
filterwill removemoistureandcontaminants fromthe
air stream when using compressed air. The filter is
capable of filtering to at least 5 microns. The filter
assembly is pre-assembled at the factory and need
only be attached to the power supply.
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. Smart Cart
Steel cart on easy rolling 10" pneumatic tires to pro-
videmaximum mobilityfor the powersupply. Handle
is 3/4" tubing with hooks for storage of torch leads.
A tie down strap is also included.
E. 575VTransformer
This step-down transformer allows the power sup-
ply to operate with 575 VAC three-phase input power.
F. Interface Cable
NOTE
This accessory can be used only with the PCM-28
Torches.
The 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.

Manual 0-2587 13 SERVICETROUBLESHOOTING
SECTION 4:
SERVICE
TROUBLESHOOTING
DIAGNOSTICS
4.01 Introduction
This Section provides service diagnostics for the Pak
Master 50XL Power Supply, allowing the Technician to
isolate any faulty Subassemblies. Refer to Section 5, Re-
pairs & Replacement Procedures, for parts replacement
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 theseparate manu-
als for that product.
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
Unit should be cleaned as described in Operating
Manual 0-2586.
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 (page 1). Be sure the operator is equipped
with proper gloves, clothing, eye and ear protec-
tion.Make sureno part ofthe operator’s bodycomes
into contact with the workpiece while the torch is
activated.
CAUTION
Sparks from the cutting process can cause damage
tocoated, painted, and othersurfaces such as glass,
plastic and metal.
NOTE
Handletorch leads with careand 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 thanto 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
bewiped offwitha welding glove. "Slow speed dross"
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
difficulttoremove. Whencutting atroublesomesteel,

SERVICETROUBLESHOOTING 14 Manual 0-2587
it is sometimes useful to reduce the cutting speed to
produce "slow speed dross". Any resultant cleanup
can be accomplished by scraping, not grinding.
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
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
3. Excessive Dross Formation
a. Cutting speed too slow
b. Torch standoff too high from workpiece
c. Worn torch parts
d. Improper cutting current
4. Short Torch Parts Life
a. Oil or 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 is a process which
should be undertaken only by those familiar with high
voltage high power electronic equipment.
B. AdvancedTroubleshooting
NOTE
For basic troubleshooting and parts replacement
procedures refer to Pak Master 50XL Operating
Manual 0-2586.
The advanced troubleshooting covered in this Service
ManualrequiresPower Supplydisassembly andlive mea-
surements. It is helpful for solving many of the common
problems that can arise with the Pak Master 50XLPower
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.
Sub-section4.09 includesspecific test proceduresand LED
status identification tables. The sub-section is referenced
by the troubleshooting guide for the specific test to be
performed.
Thetroubleshootingguide has six sub-sections asfollows:
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