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YOU ARE IN GOOD COMPANY! The Brand of Choice for Contractors and Fabricators Worldwide. Thermal Arc is a Global Brand of Arc Welding Products for Thermadyne Industries Inc. We manufacture and supply to major welding industry sectors worldwide including; Manufacturing, Construction, Mining, Automotive, Aerospace, Engineering, Rural and DIY/Hobbyist.
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While the information contained in this Manual represents the Manufacturer's best judgement, the Manufacturer assumes no liability for its use. ArcMaster 400 MST Inverter Arc Welder Instruction Manual Number 0-4905 for: Part Number 10-3089 Published by: Thermadyne Industries Inc.
TABLE OF CONTENTS SECTION 1: SAFETY INSTRUCTIONS AND WARNINGS ..............1 SYMBOL LEGEND ......................... 11 SECTION 2: INTRODUCTION AND DESCRIPTION ............... 12 2.01 How to Use This Manual ..........................12 2.02 Equipment Identification ..........................12 2.03 Receipt of Equipment..........................12 2.04 Description ..............................
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11.03 Switching VRD On/Off..........................50 SECTION 12: POWER SOURCE ERROR CODES ................52 APPENDIX A - INTERCONNECT DIAGRAM ..................55 APPENDIX B - ARCMASTER 400 MST ACCESSORIES ............... 57 LIMITED WARRANTY AND SCHEDULE GLOBAL CUSTOMER SERVICE CONTACT INFORMATION..........Inside Rear Cover...
ARCMASTER 400 MST SECTION 1: SAFETY INSTRUCTIONS AND WARNINGS WARNING PROTECT YOURSELF AND OTHERS FROM POSSIBLE SERIOUS INJURY OR DEATH. KEEP CHILDREN AWAY. PACEMAKER WEARERS KEEP AWAY UNTIL CONSULTING YOUR DOCTOR. DO NOT LOSE THESE INSTRUCTIONS. READ OPERATING/INSTRUCTION MANUAL BEFORE INSTALLING, OPERATING OR SERVICING THIS EQUIPMENT.
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ARCMASTER 400 MST 3. Use protective screens or barriers to protect others from flash and glare; warn others not to watch the arc. WARNING 4. Wear protective clothing made from durable, flame-resistant material (wool and leather) and foot protection. WELDING can cause fire or explosion.
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ARCMASTER 400 MST 2. If used in a closed area, vent engine exhaust outside and away from any building air intakes. WARNING WARNING FLYING SPARKS AND HOT METAL can cause injury. Chipping and grinding cause flying metal. As welds cool, they can throw off slag.
ARCMASTER 400 MST 1.02 Principal Safety Standards Safety in Welding and Cutting, ANSI Standard Z49.1, from American WARNING Welding Society, 550 N.W. LeJeune Rd., Miami, FL 33126. Safety and Health Standards, OSHA 29 CFR 1910, from Superintendent STEAM AND PRESSURIZED HOT COOLANT can burn of Documents, U.S.
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ARCMASTER 400 MST 1.03 Precautions de Securite en Soudage à l’Arc MISE EN GARDE LE SOUDAGE A L’ARC EST DANGEREUX PROTEGEZ-VOUS, AINSI QUE LES AUTRES, CONTRE LES BLESSURES GRAVES POSSIBLES OU LA MORT. NE LAISSEZ PAS LES ENFANTS S’APPROCHER, NI LES PORTEURS DE STIMULATEUR CARDIAQUE (A MOINS QU’ILS N’AIENT CONSULTE UN MEDECIN). CONSERVEZ CES INSTRUCTIONS.
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ARCMASTER 400 MST AVERTISSEMENT AVERTISSEMENT LES VAPEURS ET LES FUMEES SONT DANGEREUSES LE RAYONNEMENT DE L’ARC PEUT BRÛLER LES YEUX POUR LA SANTE. ET LA PEAU; LE BRUIT PEUT ENDOMMAGER L’OUIE. Le soudage dégage des vapeurs et des fumées L’arc de soudage produit une chaleur et des rayons dangereuses à...
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ARCMASTER 400 MST 7. Ne soudez des tôles galvanisées ou plaquées au plomb ou au cadmium que si les zones à souder ont été grattées à fond, que si AVERTISSEMENT l’espace est bien ventilé; si nécessaire portez un respirateur à ad- duction d’air.
ARCMASTER 400 MST Les accumulateurs contiennent de l’électrolyte acide et 1. Utilisez l’équipement à l’extérieur dans des aires ouvertes et bien ventilées. dégagent des vapeurs explosives. 2. Si vous utilisez ces équipements dans un endroit confiné, les 1. Portez toujours un écran facial en travaillant sur un accumu-lateur.
ARCMASTER 400 MST 1.06 Declaration Of Conformity Manufacturer: Thermadyne Corporation Address: 82 Benning Street West Lebanon, New Hampshire 03784 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.
SYMBOL LEGEND Amperage STICK (Shielded Metal Arc SMAW) Voltage Pulse Current Function Hertz (frequency) Spot Time (GTAW) Seconds Remote Control (Panel/Remote) Percent Remote Function DC (Direct Current) Arc Control (SMAW) AC (Alternating Current Gas Post-Flow Standard Function Gas Pre-Flow Slope Function Voltage Reduction Device Circuit Slope W/Repeat Function Negative...
Owner’s Manual number and equipment identification numbers. Electronic copies of this manual can also be downloaded at no charge in Acrobat PDF format by going to the Thermal Arc web site listed below and clicking on the Literature Library link: http://www.thermalarc.com...
2.04 Description ™ The Thermal Arc ARC MASTER 400 MST is a single & three-phase DC arc welding power source with Constant Current (CC) and Constant Voltage (CV) output characteristics. This unit is equipped with a Digital Volt/Amperage, lift arc starter for use with Gas Tungsten Arc Welding (GTAW), Arc Control and Hot Start for Shielded Metal Arc Welding (SMAW), Inductance Control for Gas Metal Arc Welding (GMAW) processes.
2.05 Functional Block Diagram Figure 2 illustrates the Functional Block Diagram of the 400 MST-power supply. Input Hall Current Main Input IGBT Output Main Capacitor Circuit Diode Inverter Diodes Transformers Transformer Power Switch DC Power Themal Themal (T1) (HCT1) Filter Detector Detector Primary...
WARNING 3 Thermal Arc advises that this equipment be electrically connected by a qualified electrician. 3.03 Electrical Input Connections WARNING 4 ELECTRIC SHOCK can kill; SIGNIFICANT DC VOLTAGE is present after removal of input power.
3.04 Electrical Input Requirements Operate the welding power source from a single or three-phase 50/60 Hz, AC power supply. The input voltage must match one of the electrical input voltages shown on the input data label on the unit nameplate. Contact the local electric utility for information about the type of electrical service available, how proper connections should be made, and inspection required.
The ARC MASTER 400MST is designed for use with a generator as an input power source. Contact an accredited Thermal Arc service agent for the proper sizing and set-up recommendations of a generator power source system. As a general rule, depending on the type of generator used, the generator capacity should be twice the maximum rating of the welder.
3.07 High Frequency Interference Interference may be transmitted by a high frequency initiated or stabilized arc-welding machine in the following ways: Direct Radiation Radiation from the machine can occur if the case is metal and is not properly grounded. It can occur through apertures such as open access panels.
No Load 400V Thermal Arc continuously strives to produce the best product possible and therefore reserves the right to change, improve or revise the specifications or design of this or any product without prior notice. Such updates or changes do not entitle the buyer of equipment previously sold or shipped to the corresponding changes,...
SECTION 4: OPERATOR CONTROLS 4.01 ARC MASTER 400 MST Controls Figure 4. ARC MASTER 400 MST Power Source Control Knob Socket Pin Function This control sets the selected weld 24VAC auxiliary high side. parameter, rotating it clockwise increases Input to energize solid state contactor the parameter and is indicated on the digital (Contact closure between pin A and meter.
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Positive Terminal Welding current flows from the Power Source via heavy duty Dinse type terminal. It is essential, however, that the male plug is inserted and turned securely to achieve a sound electrical connection. Negative Terminal Welding current flows from the Power Source via heavy duty Dinse type terminal. It is essential, however, that the male plug is inserted and turned securely to achieve a sound electrical connection.
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6. ON/OFF Switch This switch connects the Primary supply voltage to the inverter when in the ON position. This enables the Power Supply. WARNING 5 When the welder is connected to the Primary supply voltage, the internal electrical components may be at 500V potential with respect to earth. Input Cable The input cable connects the Primary supply voltage to the equipment.
4.02 Weld Parameter Descriptions for ARC MASTER 400 MST Figure 5. ARC MASTER 400 MST Front Panel with Parameter Description Parameter Description This parameter provides a suitable short circuit current in STICK welding to improve electrode sticking and arc stability. ARC CONTROL This parameter operates in STICK weld mode and is used to improve the start characteristics for stick electrodes.
Parameter Description Selects in operation Panel board or Remote. Operation PANEL/REMOTE This parameter, similar to the ARC CONTROL in STICK mode, allows for the adjustment of the dynamic property of the arc. As the inductance is increased the INDUCTANCE output voltage may need to be adjusted to achieve the desired weld characteristics. The SAVE/LOAD buttons are used to save and retrieve a total number of 5 programs into the 400 MST memory.
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HOT START This parameter operates in STICK mode and improves the start characteristics for stick electrodes. e.g. low hydrogen electrodes. It sets the peak start current on top of the WELD current. e.g. HOT START current = 150 amps when Weld Current = 100 amps & HOT START = 50A WELD (A) This parameter sets the STICK &...
Vertical up welding When welding vertical up with arc force on, the operator can control the amount of current by changing arc length, i.e. voltage. Weld metal is deposited by “digging” the electrode into the side of the base metal joint and then increasing the arc length with a flicking motion, to allow the weld pool to freeze, before digging the electrode into the other side of the base metal joint.
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Feature Description Voltage Reduction Device (VRD) Reduces the OCV when the power supply is not in use. (shipped activated, field-capable) Eliminates the need for add on voltage reducers and has no effect on arc starting. • See Section 11 for de-activation VRD fully complies to IEC 60974-1 instructions.
SECTION 5: SEQUENCE OF OPERATION NOTE: Parameter Buttons are used to select the parameters to be set. The LED’s show which function is being adjusted on the weld sequence graph. Refer to Symbols Table located in the front of the manual for Symbol descriptions. Figure 6.
5.01 Stick Welding • Connect work lead to negative terminal • Connect electrode lead to positive terminal • Switch machine on • Set weld current • Set Contactor • Connect remote control device if required Use the Scroll Buttons to move to the parameter to be set. The LED will show which function is being adjusted on the weld sequence graph.
5.03 MIG Welding • Connect work lead to negative terminal • Connect electrode lead to positive terminal • Switch machine on • Set weld voltage • Set Inductance • Connect Wire feeder • Set wire feed speed (IPM) Use the Scroll Buttons to move to the parameter to be set. The LED will show which function is being adjusted on the weld sequence graph.
SECTION 6: BASIC TIG WELDING GUIDE 6.01 Electrode Polarity Connect the TIG torch to the - / TORCH terminal and the work lead to the + / WORK terminal for direct current straight polarity. Direct current straight polarity is the most widely used polarity for DC TIG welding. It allows limited wear of the electrode since 70% of the heat is concentrated at the work piece.
6.07 Welding Parameters for Steel Base Metal DC Current for DC Current for Tungsten Filler Rod Argon Gas Thickness Mild Steel Stainless Electrode Diameter Flow Rate Joint Type Steel Diameter (if required) Liters/min 35-45 20-30 Butt/Corner 0.040” 0.040” 1/16” 40-50 25-35 Lap/ Fillet 1.0mm...
SECTION 7: BASIC STICK WELDING GUIDE 7.01 Electrode Polarity Stick electrodes are generally connected to the ‘+’ terminal and the work lead to the ‘−’ terminal but if in doubt consult the electrode manufacturers literature. 7.02 Effects of Stick Welding Various Materials High tensile and alloy steels The two most prominent effects of welding these steels are the formation of a hardened zone in the weld area, and, if suitable precautions are not taken, the occurrence in this zone of under-bead cracks.
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Metals being joined Electrode Comments Copper, Bronze, Brass, etc. Bronze Easy to use electrode for marine fittings, water taps and valves, water trough float 5.7 ERCUSI-A arms, etc. Also for joining copper to steel and for bronze overlays on steel shafts. High Alloy Steels, 312-16 It will weld most problematical jobs such...
SECTION 8.0 BASIC MIG WELDING GUIDE 8.01 Setting of the Power Source The setting of the ARC MASTER 400 MST requires some practice by the operator, the welding Power Source/Wirefeeder having two control settings that have to balance. These are the Wirespeed control and the Voltage Control.
8.04 Travel Speed Speed at which a weld travels influences the width of the weld and penetration of the welding run. 8.05 Electrode Wire Size Selection The choice of electrode wire size in conjunction with shielding gas used depends on: The position of welding Thickness of the metal to be welded The deposition rate required...
Turn Power Switch to OFF before proceeding. Internal cleaning of the unit should be done every 6 months by an authorized Thermal Arc Service Center to remove any accumulated dirt and dust. This may need to be done more frequently under exceptionally dirty conditions.
WARNING There are extremely dangerous voltages and power levels present inside this product. Do not attempt to open or repair unless you are an accredited Thermal Arc Service Agent and you have had training in power measurements and troubleshooting techniques.
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WARNING Disengage the drive roll when testing for gas flow by ear. Inconsistent Wire Feed Checking the following points can reduce wire-feeding problems: 1. Wire spool brake is too tight. Feed roller driven by motor in the cabinet will slip. 2.
E Cooling rate too fast. E Slow the cooling rate by preheating part to be welded or cool slowly. Faulty rectifier unit. Have an accredited Thermal Arc Service Agent Cold weld to test then replace the faulty component. puddle. Loose welding cable connection.
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The MIG torch has been connected Connect the MIG torch to the positive (+) Arc does not to the wrong voltage polarity on the welding terminal for solid wires and gas have front panel. shielded flux cored wires. Refer to the a crisp sound, electrode wire manufacturer for the that short arc...
10.03 TIG Welding Problems Weld quality is dependent on the selection of the correct consumables, maintenance of equipment and proper welding technique. Description Possible Cause Remedy Excessive beard Welding current is too low. Increase weld current and/or build-up or poor faulty joint preparation.
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Description Possible Cause Remedy Electrode melts or A No gas flowing to A Check the gas lines for kinks oxidizes when an arc welding region. or breaks and gas cylinder is struck. contents. B Torch is clogged with dust. B Clean torch. C Gas hose is cut.
Description Possible Cause Remedy 12 Arc start is not A Tungsten electrode is too A Select the right size electrode. smooth. large for the welding current. Refer to Basic TIG Welding Guide. B The wrong electrode is being B Select the right electrode type. used for the welding job.
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Description Possible Cause Remedy 4 Portions of the Small electrodes used on Use larger electrodes and weld run do not heavy cold plate. pre-heat the plate. fuse to the surface Welding current is too low. Increase welding current. of the metal or edge of the joint.
10.05 Power Source Problems Description Possible Cause Remedy 1 The welding arc The Primary supply voltage Switch ON the Primary cannot be has not been switched ON. supply voltage. established. The Welding Power Source Switch ON the Welding switch Power Source. is switched OFF.
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Description Possible Cause Remedy SLOPE Gas flow won’t A Weld Mode ( A Strike an arc to complete the REPEAT SPOT shut OFF. ) was weld cycle. POST-FLOW changed before gas time had finished. Switch machine OFF then ON reset solenoid valve sequence. B Gas valve is faulty.
In addition to the above tests and specifically in relation to the VRD fitted to this machine, the following periodic tests should also be conducted by an accredited Thermal Arc service agent. Description...
11.03 Switching VRD On/Off Switch the machine OFF. a) Remove the clear plastic cover from the control panel. (see Figure 11) • Lift up the cover so it rests ON the top of the unit. • Place a small flat bladed screw driver between the cover hinge on the front panel. •...
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d) Turning the VRD ON/OFF (see Figure 13). • To turn VRD ON: rotate the trim potentiometer (VR1) on the display PCB fully clockwise. When VRD is turned ON check that it operates as per VRD Specifications on page 49. •...
80ºC for about 1 Fan ceases to Have an accredited Fan operates at max second. operate. Thermal Arc Service speed. Agent investigate. E01 resets when TH1 Air flow is restricted Unblock vents then decreases by vents being let Power Source to 70ºC for about 30...
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6 E12 error code displayed Mains supply Have an accredited Weld current ceases. Under mains supply voltage is down to a Thermal Arc Service Buzzer sounds (input) voltage primary dangerously low Agent or a qualified constantly. capacitors is reduced for level.
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Remarks 13 E94 error code displayed The Welding Power Have an accredited Weld current ceases. Temperature sensor TH1 Source’s Thermal Arc Service Buzzer sounds for IGBTs or sensor TH2 temperature sensors Agent check or constantly. for secondary diodes are have malfunctioned.
APPENDIX B - ARCMASTER 400 MST ACCESSORIES PART NO. DESCRIPTION 10-2007 Remote Foot control 7.6m lead and plug 10-2005 Remote Hand Pendant 7.6m lead and plug 10-2096 14 Pin Plug for Remote or TIG Torch Button 10-2097 Cable Clamp for 14 Pin Plug...
LIMITED WARRANTY AND SCHEDULE This information applies to Thermadyne products that were purchased in the United Kingdom April 2006 Thermadyne guarantees the proposed product to be free from defects in material or workmanship when operated in accordance with the written instructions as defined in the owner’s manual supplied with the machine. Thermadyne welding products are manufactured for use by commercial and industrial users and trained personnel with experience in the use and maintenance of electrical welding and cutting equipment.
GLOBAL CUSTOMER SERVICE CONTACT INFORMATION Thermadyne Asia Sdn Bhd Thermadyne USA Lot 151, Jalan Industri 3/5A 2800 Airport Road Rawang Integrated Industrial Park - Jln Batu Arang Denton, Tx 76207 USA 48000 Rawang Selangor Darul Ehsan Telephone: (940) 566-2000 West Malaysia 800-426-1888 Telephone: 603+ 6092 2988 Fax: 800-535-0557...
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World Headquarters Thermadyne Holdings Corporation Suite 300, 16052 Swingley Ridge Road St. Louis, MO 63017 Telephone: (636) 728-3000 Fascimile: (636) 728-3010 Email: sales@thermalarc.com www.thermalarc.com...
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