Thermal Arc 281 FABRICATOR Service Manual Download Page 78

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FABRICATOR 281

CIRCUIT OPERATION

Manual No. 0-4880B

CONNECTOR JB

Terminal

JB-1

wiper of wire speed control potentiometer,

varies between <2V to approximately 4.7VDC

(pot wiper)

reference

JA-5 or JB-5

Terminal

JB-2

wire speed control potentiometer minimum (pot

low) approximately 2VDC

reference

JA-5

Terminal

JB-3

wire speed control potentiometer maximum

approximately 4.7VDC

reference

JA-5

Terminal

JB-4

32VAC supply from auxiliary winding on fan

reference

JA-5 or JB-5

Terminal

JB-5

PCB common. Return for 32VAC supply from

auxiliary winding on M1

Terminal

JB-6

Motor positive terminal 0VDC - 24VDC with

speed pot

reference

JB-8

Terminal

JB-7

negative welding output voltage

reference

JB-9

Terminal

JB-8

Motor negative terminal 0VDC to -24VDC with

speed pot

reference

JB-6

Terminal

JB-9

positive welding voltage

Terminal

JB-10

return for 32VAC supply from auxiliary winding

on M1

reference

JB-5

Terminal

JB-11

relay contact to control SOL1 & W1

closes to complete circuit to JB-10

reference

JB-4

CONNECTOR JB

Torch circuit jumper installed

8.02 Circuit Operation Of The MIG Timer

PCB 7977965

This board is connected by way of a 6-way cable and

does not have any terminals available to measure.

8.03 Circuit Operation Of The Digital

Volt/Amp PCB 704883

Terminal

X13/1

24VAC supply for board

measure 24VAC wrt X13/3

Terminal

X13/2

no connection

Terminal

X13/3

24VAC supply for the board

measure 24VAC

wrt X13/1

Terminal

X13/4

PCB common, weld volts negative

shunt negative PCB 0V

Terminal

X13/5

shunt positive

measure a few hundred mV

wrt X13/4 when welding output is loaded

Terminal

X13/6

weld volts positive

measure welding output voltage

wrt X13/4

Summary of Contents for 281 FABRICATOR

Page 1: ...Art A 09904 208 V Hz 1 fabricator MIG Welding machine 281 Service Manual Version No AG Issue Date December 16 2010 Manual No 0 4880B Operating Features ...

Page 2: ...utions They will help you to avoid potential hazards that may exist when working with this product 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 Aerosp...

Page 3: ...4 603 298 5711 www thermalarc com Copyright 2006 by Thermadyne Industries Inc All rights reserved Reproduction of this work in whole or in part without written permission of the pub lisher 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 accide...

Page 4: ...2 10 Included Items 2 6 2 11 Optional Accessories 2 6 SECTION 3 INSTALLATION 3 1 3 01 Environment 3 1 3 02 Location 3 1 3 03 Ventilation 3 1 3 04 Primary Input Voltage Requirements 3 2 3 05 Alternative Primary Input Voltages 3 2 3 06 Quick Setup 3 4 3 07 Mount the A2281 Wire Feeder 3 5 3 08 Installation of Shielding Gas GMAW Process 3 5 3 09 Attaching the Gun and Cable Assembly to the Remote Feede...

Page 5: ... Troubleshooting 6 1 6 02 Solving Problems Beyond the Welding Terminals 6 1 6 03 Welding Problems 6 3 6 04 Power Supply Problems 6 5 6 05 Wire Feeder Problems 6 6 SECTION 7 ADVANCED TROUBLESHOOTING 7 1 7 01 Preliminary Checks 7 1 7 02 Initial Setup Conditions 7 2 7 03 Primary Power Test 7 2 7 04 Logic and Control Tests 7 3 7 05 Spool Gun Control J1 Test 7 4 7 06 Output Voltage Test 7 5 7 07 Wire F...

Page 6: ...nt Parts 1 9 2 9 04 Power Supply External Replacement Parts 2 9 4 9 05 Power Supply Electrical Replacement Parts 9 5 9 06 Remote Parts 1 9 6 9 07 Remote Parts 2 9 7 9 08 Remote Parts 3 9 8 9 09 Remote Electrical Components 1 9 9 9 10 Remote Wire Feeder Parts 9 10 9 11 MIG Torch 9 12 APPENDIX 1 OPTIONAL ACCESSORIES AND CONSUMABLES A 1 APPENDIX 2 POWER SUPPLY CIRCUIT DIAGRAM A 2 APPENDIX 3 MAIN PCB ...

Page 7: ...ipment with DC output 14 Wear a safety harness to prevent falling if working above floor level 15 Keep all panels and covers securely in place WARNING ARC RAYS can burn eyes and skin NOISE can damage hearing Arc rays from the welding process produce intense heat and strong ultraviolet rays that can burn eyes and skin Noise from some processes can damage hearing 1 Wear a welding helmet fitted with ...

Page 8: ...metal 2 Do not weld where flying sparks can strike flammable material 3 Remove all flammables within 35 ft 10 7 m of the welding arc If this is not possible tightly cover them with approved covers 4 Be alert that welding sparks and hot materials from welding can easily go through small cracks and openings to adjacent areas 5 Watch for fire and keep a fire extinguisher nearby 6 Be aware that weldin...

Page 9: ...xhaust gases 1 Use equipment outside in open well ventilated areas 2 If used in a closed area vent engine exhaust outside and away from any building air intakes WARNING ENGINE FUEL can cause fire or explosion Engine fuel is highly flammable 1 Stop engine before checking or adding fuel 2 Do not add fuel while smoking or if unit is near any sparks or open flames 3 Allow engine to cool before fueling...

Page 10: ... based ad vice on strategies to minimize or avoid potential risks To reduce magnetic fields in the workplace use the following procedures 1 Keep cables close together by twisting or taping them 2 Arrange cables to one side and away from the operator 3 Do not coil or drape cable around the body 4 Keep welding power source and cables as far away from body as practical ABOUT PACEMAKERS The above proc...

Page 11: ...la mise en marche En soudage automatique ou semi automatique avec fil ce dernier le rouleau ou la bobine de fil le logement des galets d entrainement et toutes les pièces métalliques en con tact avec le fil de soudage sont sous tension Un équi pement inadéquatement installé ou inadéquatement mis à la terre est dangereux 1 Ne touchez pas à des pièces sous tension 2 Portez des gants et des vêtements...

Page 12: ...er l oxygène de l air et ainsi causer des malaises ou la mort Assurez vous que l air est propre à la respiration 6 Ne soudez pas à proximité d opérations de dégraissage de nettoyage ou de pulvérisation La chaleur et les rayons de l arc peuvent réagir avec des vapeurs et former des gaz hautement toxiques et irritants 7 Ne soudez des tôles galvanisées ou plaquées au plomb ou au cadmium que si les zo...

Page 13: ...sent des particules métalliques volantes En refroidissant la soudure peut projeter du éclats de laitier 1 Portez un écran facial ou des lunettes protectrices approu vées Des écrans latéraux sont recommandés 2 Portez des vêtements appropriés pour protéger la peau AVERTISSEMENT LES BOUTEILLES ENDOMMAGEES PEUVENT EX PLOSER Les bouteilles contiennent des gaz protecteurs sous haute pression Des bouteil...

Page 14: ...vant de connecter ou de déconnecter des câbles d accumulateur 3 N utilisez que des outils anti étincelles pour travailler sur un ac cumulateur 4 N utilisez pas une source de courant de soudage pour charger un accumulateur ou survolter momentanément un véhicule 5 Utilisez la polarité correcte et de l accumulateur AVERTISSEMENT LA VAPEUR ET LE LIQUIDE DE REFROIDISSEMENT BRULANT SOUS PRESSION PEUVENT...

Page 15: ... certain operating procedures Additional copies of this manual may be purchased by contacting Thermadyne at the address and phone number in your area listed in the inside back cover of this manual Include the Service 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 list...

Page 16: ...AW Increase Decrease Circuit Breaker AC Auxiliary Power Remote Duty Cycle Percentage Amperage Voltage Hertz cycles sec Frequency Negative Positive Direct Current DC Protective Earth Ground Line Line Connection Auxiliary Power Receptacle Rating Auxiliary Power Art A 04130 115V 15A t t1 t2 X IPM MPM t V Fuse Wire Feed Function Wire Feed Towards Workpiece With Output Voltage Off Preflow Time Postflow...

Page 17: ...fied electrician Ensure the Power Supply is grounded correctly electrically in accordance with local regulations Excessive heat in the welding cables may cause fire Never weld with poor electrical connections damaged welding cables or exceed the welding cable current rating as this will produce excessive heat and may cause a fire Always wear the correct protective clothing for protection from spar...

Page 18: ...ermal Arc Wire Drive Specifications Control Circuit Supply 30VA 32VAC Wire Motor Supply 216VA 36VAC Wire Speed Range 80 to 800 ipm 2 to 20 m min Wire Diameter 023 0 6mm 030 0 8mm 035 0 9mm 045 1 2mm 1 16 1 6mm Mild Steel Y Y Y Y Stainless Steel Y Y Y Y Aluminum Y Y Y Y Flux Cored Y Y Y Y Wire Spool Size Capacity 44 lb 33 lb 10 lb 8 and 12 wire spool sizes Table 2 3 Wire Drive Specifications 2 08 D...

Page 19: ...F 250A 26 5V 60 250A 26 5V 60 Maximum Duty Cycle 104ºF 300A 29 0V 40 300A 29 0V 40 100 Duty Cycle Output Rating 104ºF 195A DC at 24V 195A DC at 24V Duty Cycle Period 10 minutes Number of Output Voltage Values 24 Electrode Wire Type and Diameter Mild Stainless Steel 023 0 6mm 045 1 2mm Aluminum 030 0 8mm 1 16 1 6mm Flux Cored 030 0 8mm 1 16 1 6mm Wire Feed Speed Range 80 800 ipm 2 20 m min Wire Spo...

Page 20: ...er Rack Factory Fitted Primary Power Cable 8AWG 10ft 3m with Plug NEMA 6 50P Work Lead 26 ft 8m Cable Storage Hooks Gas Regulator Flowmeter Argon Mix Gases Tweco Weldskill MIG Gun 300 Amp 15ft 4 5m Fitted Feed Roll for 035 045 0 9 1 2mm solid wire Table 2 5 Power Supply Contents 2 11 Optional Accessories Refer to the Appendix section of this manual for the list of available options and accessories...

Page 21: ...siderably reduces the skin resistance of the human body and the insulation properties of accessories Environments with increased hazard of electric shock do not include places where electrically conductive parts in the near vicinity of the operator which can cause increased hazard have been insulated 3 02 Location Be sure to locate the Power Supply according to the following guidelines In areas fr...

Page 22: ...ted to the Fabricator 281 3 05 Alternative Primary Input Voltages WARNING The Fabricator 281 input power supply lead should be replaced with leads as specified in Table 3 2 when the Fabricators input power supply voltage is changed The Power Supply is suitable for use on the following input power supply voltages Input Power Supply Voltage Setting Primary Input Supply Lead Size Input Power Outlet S...

Page 23: ...e selection block Loosen the set screw for both voltage locations 3 Remove the blue wires from the current location and Insert them into the new voltage location Secure by tightening the set screw onto the uninsulated portion of the wires Secure the other voltage set screw as well 230V connection 208V connection Art A 07332 Figure 3 1 Voltage selections for Fabricator 281 Wired for 230V ...

Page 24: ...acket with the chain provided If this arrangement is not used then ensure that the gas cylinder is secured to a building pillar wall bracket or otherwise securely fixed in an upright position WARNING If the gas cylinder is not secured to the cylinder tray the power supply must be kept from moving to avoid over extending the gas hose which can result in personal injury damage to the power supply fl...

Page 25: ...nterconnection Cable Assembly to the the A2281 wire feeder s rear panel by firmly threading each of the three cables connectors to their mating sockets Use the power supply end of the cable as a reference guide as shown in Figure 3 3 To Positive Welding Terminal To Gas Regulator 26ft 8m Interconnection Cable Assembly To 7 pin Amphenol Socket on Front Panel Art A 07455_AB Figure 3 3 Attach the Inte...

Page 26: ...ttach supplied gas line between the regulator output and the desired input at the rear of the power supply depending on Spool Gun or MIG Gun use Refer to Figure 3 5 5 and 3 15 Adjusting Regulator Adjust control knob of regulator to the required flow rate indicated on gauge dial Refer to Figure 3 4 and data charts Approx 20 CFH The gas flow rate should be adequate to cover the weld zone to stop wel...

Page 27: ...80B 3 INSTALLATION Regulator and Flowmeter Cap Cracking 1 2 3 4 5 Gas Hose Art A 07964 Shielding Gas Shielding Gas Stowage Hook Shielding Gas Shielding Gas 1 1 8 To A2281 Wire Feeeder Gas Inlet Figure 3 5 Gas Cylinder Installation ...

Page 28: ...hanism and pulling the cover outward and up Art A 07457_AB Figure 3 6 Door Panel Opening NOTE Lubricate the O ring on the quick connect fitting of the gun cable with grease Dow company 4 compound or equivalent or Thermal Arc 903910 2 Route the gun cable through the access hole in the front panel Refer to Figures 3 6 and 3 7 3 Loosen the thumbscrew and insert the gun cable end as far as it will go ...

Page 29: ...ALLATION Thumbscrew Art A 07459 Figure 3 8 Mount Gun Cable to Adapter Socket 3 10 Selection and Installation of Feedrolls A Feedroll consists of two different sized grooves As delivered from the factory the feedroll is installed for 035 045 ...

Page 30: ...thest from the stamped marking When mounted that will be the groove closest to the motor and the one to thread To ensure proper wire feed the groove closest to the motor must match the electrode wire size being used 045 1 2mm Groove Art A 07150 The size that is visible when fitting the feedroll is the groove size in use 045 1 2 045 1 2mm Stamping Figure 3 9 Feedroll Example NOTE All grooved feed r...

Page 31: ...ls that cover the entire hub 5 Replace the Wire Spool Hub Nut by turning clock wise to the right NOTE The Hub tension has been pre adjusted at the factory However if adjustment is required refer to section 3 15 and Figure 3 13 CAUTION Use care in handling the spooled wire as it will tend to unravel when loosened from the spool Grasp the end of the wire firmly and don t let go of it h Art A 07460 W...

Page 32: ...ove is being used Second part of Figure 3 11 4 Pass the wire through the outlet guide and into the Gun liner of the Gun Cable Second part of Figure 3 11 5 Close the Pressure Roller Arm Figure 3 12 6 Swing the Spring Pressure Adjusting Knob back into place Figure 3 12 7 Use the Spring Pressure Adjusting Knob to create a snug condition Clockwise to tighten and Counter Clockwise to loosen Figure 3 12...

Page 33: ...re may cause rapid wear of the feed roller motor shaft and motor bearings NOTE Genuine TWECO contact tips and liners should be used Many non genuine liners use inferior materials which can cause wire feed problems 3 15 Wire Spool Hub Brake The wire spool hub incorporates a friction brake which is adjusted during manufacture for optimum braking If it is considered necessary adjustment can be made b...

Page 34: ...ar Panel Spool Gun Gas Input Connection Main Gun Gas Input Connection Spool Gun Interface Amphenol Receptacle Spool Gun Gas Outlet Connection Art A 07477_AB Spool Gun Welding Cable Connection Figure 3 14 Spool Gun Connections NOTE When the SPOOL GUN is properly attached and the trigger is depressed the system automatically disables the internal wire feed and gas controls and selects the SPOOL GUN ...

Page 35: ...d electrode wires 1 D C Electrode Positive DCEP Reverse Polarity 1 Connected to Pos output terminal 1 Connected to Neg output terminal 2 FCAW Gasless Flux Cored electrode wire 2 D C Electrode Negative DCEN Straight Polarity 2 Connected to Neg output terminal 2 Connected to Pos output terminal Table 3 3 Process Cable Connections Art A 07479 Cable from wirefeeder connected to terminal Cable to work ...

Page 36: ...ine Refer to Figures 3 15 and 3 16 b Remove both terminal knobs by rotating counterclockwise c Set up the desired lead polarity as per Table 3 3 and as shown in Figures 3 15 or 3 16 d Place the Work Lead cable on the opposite terminal e Replace both terminal knobs and tightly secure them to ensure good electrical connections CAUTION Ensure terminal knobs are tightly secured and that there is no co...

Page 37: ...Hole Wire Speed Control Spool Gun Interface Amphenol Receptacle Positive Welding Terminal Negative Welding Terminal Thermal Overload Indicator Art A 07462_AB Wirefeeder Interface Amphenol Receptacle Selector Switch Selector Switch Figure 4 1 Fabricator 281 Controls SECTION 4 OPERATION 4 01 Power Supply Controls Indicators and Features WARNING DO NOT TOUCH the electrode wire while it is being fed t...

Page 38: ...l components are at Mains voltage potential Digital Display The Digital Display allows for accurate monitoring 5 tolerance of welding current and voltage to facilitate precise welding condition adjustments Value displayed for 157 Amp Value displayed for 21 9 Volts Art A 07279 Figure 4 2 Digital Display The Digital Meter will display both welding current or arc voltage To toggle between the current...

Page 39: ...75 300 325 Current Amps Wire Speed IPM 030 STEEL 035 STEEL 045 STEEL 0 2 3 S T E E L Art A 07451 STEEL Figure 4 3 Steel AMP to IPM Conversion 0 100 200 300 400 500 600 700 800 900 25 50 75 100 125 150 175 200 225 250 275 300 325 Current Amps Wire Speed IPM 023 SS 030 SS 035 SS 045 SS Art A 07452 STAINLESS STEEL Figure 4 4 Stainless Steel AMP to IPM Conversion ...

Page 40: ...urce is operated within its duty cycle the thermal overload will not activate Refer to section 2 09 for an explanation of duty cycle and section 2 10 for the power supply specifications Wirespeed Control The Wirespeed Control knob controls the welding current via the electrode wire feed rate i e the speed of the wire feed motor Coarse Voltage Selector Switch The Coarse Voltage Selector sets the vo...

Page 41: ... 1 2 Art A 07171 Figure 4 3 Gun Switch Receptacle Spool Gun Interface Amphenol Receptacle The Spool Gun Interface Amphenol connector is used to connect a spool gun to the A2281 Wirefeeder refer to Figure 4 4 and Table 4 1 A B C D J I E F G H Art A 07181 Figure 4 4 Spool Gun 10 pin receptacle To make connections align keyway insert plug and rotate threaded collar fully clockwise The socket informat...

Page 42: ...ot suitable and it is necessary to wire a plug or cable to interface with the Wirefeeder 7pin receptacle 7 4 3 5 2 1 7 6 Art A 07478 Figure 7 Wirefeeder 7 pin receptacle Socket Pin Function 1 Output to energise the power supply contactor 32VAC contact closure is provided between socket pins 1 and 2 to energise the contactor 2 32VAC circuit active 3 Power Source thermostat 4 Power Source thermostat...

Page 43: ...MIN 1 5 7 9 3 2 4 6 8 t WELD MODE 2T SPOT STITCH 4T Figure 4 5 Internal Welding Controls WELD Mode Selector Switch The Weld Mode Selector switch selects the method of welding mode 2T Continuous Welding This mode of welding is used to weld two or more components together with a continuous weld When the MIG gun trigger switch is depressed welding commences When the MIG gun trigger switch is released...

Page 44: ...ress and hold the trigger for the complete length of the weld run WELD Spot Stitch Art A 07429_AB WELD SPOT STITCH t MIN 1 5 7 9 3 2 4 6 8 Figure 4 8 Weld Spot Stitch Control WELD MODE SPOT When the Weld Mode control is in the Spot position the Weld Spot Stitch timer controls the duration of a single spot weld WELD MODE STITCH When the Weld Mode control is in the Stitch position the Weld Spot Stit...

Page 45: ...ill 300 AMP Original Parts Installed Item Description Part No Qty 1 NOZZLE 24A 62 1 2 NOZZLE INSULATOR 34 1 3 CONTACT TIP 14 35 1 4 GAS DIFFUSER 54A 1 5 CONDUCTOR TUBE WM63J 50 1 6 HANDLE ASSY TA1 80 1 Table 4 3 MIG gun original parts consumables TWECO Weldskill MIG guns may be fitted to many different types of MIG welding Power Supplies so that your whole shop can be converted to TWECO Weldskill ...

Page 46: ... of the connector plug and the new raw end extends through the end of the conductor tube on the welding gun tighten the Allen screw in the connector plug onto the conduit to prevent its backward movement CONDUCTOR TUBE CONDUIT LINER CONDUIT LINER 1 1 16 27mm Art A 07330 REMOVE CONSUMABLES ALLEN SCREW O RINGS ALLEN SCREW CONNECTOR PLUG Figure 4 12 Conduit Trim Length NOTE When the conduit is fully ...

Page 47: ...hen changing to a different electrode wire diameter different control settings are required A thinner electrode wire needs more Wire Speed to achieve the same current level A satisfactory weld cannot be obtained if the wire speed and voltage switch settings are not adjusted to suit the electrode wire diameter and dimensions of the work piece If the Wire Speed is too high for the welding voltage st...

Page 48: ...on The choice of electrode wire size in conjunction with shielding gas used depends on Thickness of the metal to be welded Type of joint Capacity of the wire feed unit and power supply The amount of penetration required The deposition rate required The bead profile desired The position of welding and Cost of the electrode wire Weld metal deposition rate is proportional to current density Current d...

Page 49: ...Manual No 0 4880B 4 13 OPERATION Advantages of MIG welding forehand Allows superior visibility of the weld zone Flatter weld bead Shallower penetration Forehand Vertical Backhand Art A 07185 Figure 4 15 MIG Gun Angle ...

Page 50: ...fer to the spot welding nozzle table below The Fabricator 281 will operate effectively using 030 0 8mm electrode wire when spot welding Penetration depth is limited when using 024 0 6mm electrode wire for spot welding Set the controls as follows for spot welding Coarse Fine Voltage Selector Switches and Wire Feed Speed Control Select higher Voltage Selector switch positions and set the Wirespeed C...

Page 51: ...0 See below Short Circuit 92 Argon 8 CO2 All Position Welding Good coalescence and bead contour Good mechanical properties Greater than 3 32 See below Spray transfer 92 Argon 8 CO2 or minimum 98 Argon 2 O2 Flat HV Fillet Reduces undercutting Higher deposition rates and improved bead wetting Deep penetration and good mechanical properties Greater than 14 gauge 075 See below Short Circuit 98 Argon 2...

Page 52: ...56 ER 100 Ar 25cfh Steel ER70S 6 Solid or hard 100 CO2 25cfh 75 Ar 25 CO2 25cfh 8 CO 2 92 Ar 035 0 9mm 045 1 2mm 023 0 6mm 030 0 8mm 035 0 9mm 045 1 2mm 023 0 6mm 030 0 8mm 035 0 9mm 045 1 2mm 030 0 8mm 035 0 9mm Stainless Steel Stainless 7 5 Ar 90 He 2 5 CO2 35cfh ER308LSi ER309LSi ER316LSi 1 16 1 6mm 030 0 8mm 045 1 2mm 035 0 9mm 045 1 2mm 1 16 1 6mm Steel 100 CO 2 25cfh None Flux Core E71T 11 E...

Page 53: ...H 4 5 5 H 4 3 H 4 6 5 H 5 7 H 5 3 25 H 5 7 25 H 7 7 5 H 6 3 5 2 25 1 25 M 2 1 5 M 3 1 5 L 8 1 25 M 4 2 M 5 1 5 H 1 4 H 1 2 5 H 3 5 5 H 3 3 5 H 4 7 5 H 5 7 25 H 4 3 7 H 7 4 5 M 2 M 3 2 5 M 3 2 M 4 3 M 4 2 5 M 7 5 M 6 3 5 H 1 6 5 H 1 4 5 H 6 6 H 1 6 H 7 6 5 H 5 6 H 6 6 5 1 5 L 6 1 75 L 5 1 5 L 8 2 M 1 1 M 2 2 75 L 8 2 M 4 2 M 7 1 M 5 6 M 4 3 5 M 7 3 25 H 2 1 5 M 8 7 5 M 6 4 5 M 8 3 75 H 3 2 5 M 8 5 ...

Page 54: ...fabricator 281 OPERATION 4 18 Manual No 0 4880B NOTES ...

Page 55: ...u have had training in electronic measurement and troubleshooting techniques 5 01 Routine Maintenance Inspection The only routine maintenance required for the Fabrica tor 281 is a thorough cleaning and inspection with the frequency depending on the usage and the operating environment WARNING Disconnect the Fabricator from the Input power supply voltage before disassembling Special maintenance is n...

Page 56: ... of torch Consumable parts Weekly Visually inspect the torch body and consumables Visually inspect the cables and leads Replace as needed 3 Months 6 Months Replace all broken parts Visually check and use a vacuum to carefully clean the interior Maintain more often if used under severe conditions Gas and air lines Art A 07464 Clean exterior of both units ...

Page 57: ... 3 Internal gas hose in the Power Source a Ensure the hose from the solenoid valve to the MIG torch adaptor has not fractured and that it is connected to the MIG torch adaptor 4 Welding in a windy environment a Shield the weld area from the wind or increase the gas flow 5 Welding dirty oily painted oxidized or greasy plate a Clean contaminates off the plate 6 Distance between the MIG torch nozzle ...

Page 58: ...ld current to the electrode wire If the hole in the contact tip is to large then arcing may occur inside the contact tip resulting in the electrode wire jamming in the contact tip When using soft electrode wire such as aluminum it may become jammed in the contact tip due to expansion of the wire when heated A contact tip designed for soft electrode wires should be used 7 Poor work lead contact to ...

Page 59: ...hich gives higher penetration 4 Weld speed too fast a Reduce weld speed C Lack of fusion 1 Voltage too low a Increase voltage by increasing voltage selection switch position 2 Weld speed too fast a Reduce weld speed D Excessive spatter 1 Voltage too high a Lower voltage by reducing the voltage selection switch or increase wirespeed control 2 Voltage too low a Raise voltage by increasing the voltag...

Page 60: ...uce weld speed G Cold weld puddle 1 Faulty rectifier unit a Have an Accredited THERMAL ARC Service Agent to test then replace the faulty component 2 Loose welding cable connection a Check all welding cable connections 3 Low Primary Voltage a Contact supply authority 4 Weld speed too fast a Reduce weld speed H Arc does not have a crisp sound that short arc exhibits when the wirefeed speed and volta...

Page 61: ...ip burn back jam Check for clogged kinked MIG Gun conduit or worn contract tip Replace faulty component s 2 Faulty control PCB or Tweco Gun Have an Accredited Thermal Arc Service Agent investigate the fault F Wire feeds when the gun trigger switch is depressed but arc can not be established 1 P o o r o r n o w o r k l e a d connection Clean work clamp area and ensure good electrical contact G Wire...

Page 62: ...pressed 1 2 Electrode wire stuck in conduit liner or contact tip burn back jam Faulty control PCB 1 2 Check for clogged kinked MIG Torch conduit liner or worn contract tip Replace faulty components Have an Accredited Thermal Arc Service Agent investigate the fault E Wire feeds when the torch trigger switch is depressed but arc can not be established 1 Poor or no work lead contact 1 Clean work clam...

Page 63: ...ne CAUTION Do not blow air into the power supply during cleaning Blowing air into the unit can cause metal particles to interfere with sensitive electrical components and cause damage to the unit 1 Check general machine completeness 2 Check tightness of mounting and STRUCTURAL HARDWARE and all terminations and ELECTRICAL FITTINGS 3 NO DEFORMATION present to detract from machine s appearance or per...

Page 64: ...ed See figure 3 12 8 Connect gas hose to MIG Gun Gas inlet 7 03 Primary Power Test A Close primary disconnect device and observe the following 1 Green Indictor Lamp inside ON OFF Switch SW1 on the Power Supply illuminates B Set ON OFF Switch to ON position and observe the following 1 Fan turns on 2 Digital Display turns on It will display the last recorded reading for approx 5 seconds then it will...

Page 65: ...OR SWITCH to position 2T Set BURNBACK CONTROL potentiometer to maximum position Depress Gun Switch and observe the following 1 Gas flows 2 Contactor energizes 3 Feed roll turns 4 Display reads approx 15 0 V G Release Gun Switch 1 Feed Roll stops immediately 2 Display reads 15 0 V 3 After 1 seconds a Gas flow stops b Contactor de energizes 4 After 5 seconds display reads 0 0 V H Set BURNBACK CONTRO...

Page 66: ... Set FINE VOLTAGE SELECTOR SWITCH to position 8 M Connect voltmeter probes to JB 6 and J6 8 Depress the gun trigger and vary the WIRE SPEED CONTROL potentiometer from minimum to maxi mum The voltage should vary from approx 4VDC up to approx 27 VDC N Set WIRE SPEED CONTROL to 4 O Set COARSE VOLTAGE SELECTOR SWITCH to position L P Set FINE VOLTAGE SELECTOR SWITCH to position 1 This completes the Log...

Page 67: ...SSIVE READING MUST BE INCREASING IN VALUE COARSE VOLTAGE SELECTOR SWITCH SETTING FINE VOLTAGE SELECTOR SWITCH SETTING VOLTAGE 1 1 15 3 1 2 15 9 1 3 16 2 1 4 16 9 2 1 17 4 2 2 18 1 2 3 18 5 2 4 19 3 3 1 20 4 3 2 21 4 3 3 22 1 3 4 23 1 4 1 24 1 4 2 25 3 4 3 26 2 H 1 29 9 H 2 32 1 H 3 33 5 H 4 35 9 H 5 38 2 H 6 41 5 H 7 43 5 H 8 47 4 F Set COARSE VOLTAGE SELECTOR SWITCH to position L G Set FINE VOLTA...

Page 68: ...rimary input cable 3 Circuit breaker CB1 tripped a Reset breaker 4 Defective or improperly wired input power cable or plug a Measure for primary voltage at the Input Terminal Block between terminals 1 2 for 208 VAC input or between terminals 1 3 for 230VAC input see Input Terminal Block Figure 7 1 B Green Indicator in ON OFF Switch SW1 on Power Supply is illuminated When ON OFF switch SW1 is in th...

Page 69: ...e a Measure between JB 5 to JB 11 for approx 32VAC If voltage is not correct then check connections to J1 on Power Supply to A2281 Terminal Block 6 Faulty MAIN PCB PCB 1 a Measure between JB 5 to JB 11 for approx 32VAC when Gun Switch is closed If voltage is present replace PCB 1 C When gun switch is closed gas flows contactor does not energize feed roll does not turn 1 Defective Contactor W1 a Me...

Page 70: ...When Gun Switch is closed gas flows contactor closes feed roll turns but display shows 0 volts 1 Open wire between shunt and PCB4 a Measure voltage between X1 5 to X1 6 for 15VDC If voltage is not correct check continuity of wire 22 Violet 21 Orange 2 PCB 4 is defective a Measure voltage between X1 3 to X1 1 for 32VAC If voltage is correct replace PCB4 7 10 Spool Gun Control J1 Problem A Gas does ...

Page 71: ...r open work cable a Clean contact point check continuity of cable and cable to clamp connection Replace if work cable if required B Wire feed and welding problems Refer to sections 6 03 6 03 7 13 Terminal Block Voltage Test Line 1 208 V 230 V Fan Fan Main Transformer Fan Primary Note Voltage Tolerance 5V BLK WHT 208V 230V 230V Art A 07541 Figure 7 1 Input Terminal Block Diagram ...

Page 72: ...M OF SWITCH 10C RED 9 BLK 8 BRN 10A RED 10B RED 8A BRN 4 BLK 4A BLK Art A 08568 Figure7 2 3 Position Rotary Switch Coarse 13A PUR 11 GRY WIRE No S TERMINAL No S TERMINAL No S WIRE No S 3 7 11 15 1 5 9 13 10B RED 7B BLK 7C BLK TOP OF SWITCH WIRE No S TERMINAL No S TERMINAL No S WIRE No S 2 6 10 14 12A BRN 4 8 12 16 BOTTOM OF SWITCH 17 BLK 12 BRN 17A BLK 13 PUR 16 WHT 19 23 17 21 10C RED 18 22 20 24...

Page 73: ... X X 7 X 8 X X X X X X X X X X X X X 13 14 18 17 16 15 20 21 19 23 22 24 X X X X X X X X X X Art A 08570 Figure 7 5 SW3 SW4 Continuity VOLTAGE CONTROL SWITCH TEST One at a time remove SW 3 and SW 4 from front panel disconnect wires reconnect to panel and check continuity of switch per figure 7 5 Knob Locking Collar Rotary Switch SW4 Fine Set Screw Retainer Art A 08571 Figure 7 4 Rotary Switch SW3 ...

Page 74: ...3VDC Drops to 0VDC when Gun Switch is released STITCH 10 VDC for durations of STICH TIME 3 3VDC for durations of DWELL TIME Drops to 0VDC when Gun Switch is released 4T 14VDC at 1st Gun Switch closure Drops to 0VDC at second Gun Switch closure If the voltages are not found to be correct replace PCB2 To confirm the rest of the circuitry is working disconnect JC connector from Main PCB and place a j...

Page 75: ...ect JB connector from MAIN PCB 1 4 Using a meter check the diode readings between the following points Forward biased diode junction Positive meter probe on rectifier plates 2 and 3 to plates 1 4 Negative meter probe on rectifier plates 1 4 to plates 2 3 Art A 07575 1 2 3 4 Remove and isolate from rectifier assembly Figure 7 3 Rectifier Assembly Test Double forward biased junction Positive meter p...

Page 76: ...utput voltage be tween the two transformer output connections as follows COARSE VOLTAGE SELECTION FINE VOLTAGE SELECTOR VOLTAGE AC approx SWITCH SETTING SWITCH SETTING L 1 11 8 L 2 12 2 L 3 12 5 L 4 12 9 L 5 13 2 L 6 13 8 L 7 14 0 L 8 14 6 M 1 15 3 M 2 16 0 M 3 16 5 M 4 17 3 M 5 17 9 M 6 18 9 M 7 19 5 M 8 20 6 H 1 22 1 H 2 23 6 H 3 24 7 H 4 26 4 H 5 28 0 H 6 30 2 H 7 31 8 H 8 34 8 ...

Page 77: ...tage is then fed to a zener regulator to provide the 15VDC supply for the electronics on the circuit board Inputs to the Control PCB CONNECTOR JA Terminal J A 1 trigger input 40VDC trigger open approx 20VDC trigger closed reference JA 5 Terminal J A 2 trigger input 0VDC trigger open approx 20VDCV trigger closed reference JA 5 Terminal JA 3 spot timer pot 12VDCV trigger closed 0VDC trigger open ref...

Page 78: ...nal 0VDC to 24VDC with speed pot reference JB 6 Terminal JB 9 positive welding voltage Terminal JB 10 return for 32VAC supply from auxiliary winding on M1 reference JB 5 Terminal JB 11 relay contact to control SOL1 W1 closes to complete circuit to JB 10 reference JB 4 CONNECTOR JB Torch circuit jumper installed 8 02 Circuit Operation Of The MIG Timer PCB 7977965 This board is connected by way of a...

Page 79: ...y common connects to wirespeed potentiometer input of 7978050 PCB measure 0 to 5VDC depends on wire speed setting wrt 7978050 JA 5 Terminal X2 3 wirespeed relay normally closed connects to main wirespeed pot wiper measure 0 to 5VDC depends on wire speed setting wrt 7978050 JA 5 in normal setting Terminal X2 4 trigger relay connects to trigger input of 7978050 PCB Terminal X2 5 trigger relay connec...

Page 80: ...Fabricator 281 CIRCUIT OPERATION 8 Manual No 0 4880B ...

Page 81: ...responding list of parts which contains a breakdown of the equipment into assemblies subassemblies and detail parts All parts of the equipment are listed except for commercially available hardware bulk items such as wire cable sleeving tubing etc and permanently attached items which are soldered riveted or welded to other parts The part descriptions may be indented to show part relationships To de...

Page 82: ...0 251 281 1 9 See Note 1 Screw Hex HD M5x13mm Self Tap 42 10 707230WBLK Bracket Cable Hanger 251 281 1 11 7978035PKD Wheel 5 8 IDx10 OD 2 12 870921WBLKPKD Bracket Front Wheels 1 13 7977566 Castor Swivel 5 Wheel 2 14 707278PKD Panel Front Fab281 1 15 705937PKD Molding Front Fab210 251 281 1 16 707281WBLKPKD Panel Internal Fab281 1 17 705620PKD Chain 700mm Long Fabricators 1 18 871092PKD Mat Fab281 ...

Page 83: ...fabricator 281 WELDING MACHINE Manual No 0 4880B 9 PARTS LIST 6 5 4 11 3 21 20 22 2 15 1 9 14 10 7 8 12 13 16 17 Art A 07534 18 19 ...

Page 84: ...2CLAPKD Panel Top Fab281 1 2 401840 003 Cable Power Cable Fab251 281 1 3 707256WBLKPKD Panel Base Fab210 251 281 1 4 See Note 1 Screw Hex HD M5x13mm Self Tap 42 5 707276PKD Panel Side RH Fab281 1 6 871046PKD Clip Retaining 5 8 ID 2 7 7977953PKD Swivel Top Wirefeeder 1 Note 1 These parts are available at most hardware stores 1 2 3 4 5 Art A 07535 6 7 ...

Page 85: ...l Fab251 1 5 707308PKD Transformer Fab251 281 T2 1 6 7977832PKD Switch Thermostat 207 C TS1 1 7 7978038PKD Fan Assy 208 230VAC 8 24Vac M1 1 8 7977974 Terminal Output Fabricators 2 9 704978PKD Suppressor Assy Fab210 251 281 C5 1 10 871088PKD Harness Control Fab281 1 11 10 6131 Capacitor 22000uF 63V C1 C4 4 12 706502 Busbar Output Fab210 251 281 2 13 7978001PKD Contactor 32A 3 Pole 24VAC W1 1 14 797...

Page 86: ...t Fab281 1 4 7977884PKD Switch DPST Grn 16A 250V SW4 1 5 870696PKD Knob Control 1 4 IDx1 6 1 6 405376 Hub Wire Spool 1 7 7977903PKD Wheel 1 2 IDx5 OD 1 8 7977928PKD Castor Swivel 2 Wheel 2 9 7978029PKD Bushing Snap 1 69 ID 1 10 871011PKD Bushing Torch 2 11 870734 Knob Control 1 4 IDx 57 4 12 871070WBLKPKD Handle Wrfdr A2281 1 13 See Note Potentiometer 1K R1 1 14 See Note Potentiometer 100K R2 1 1 ...

Page 87: ...DESCRIPTION QTY 1 7977978 Knob Output Terminal Fabs 1 2 NB2157 Cup Retaining 1 2 ID 2 3 871067PKD Axle 1 2 Diax15 47 A2281 1 4 871068WBLKPKD Plate Mounting Castor Wrfdr 1 5 7977966PKD Swivel Base Wirefeeder 1 6 707288PKD Panel Rear A2281 1 7 7977948PKD Connector Plug 7 Pin 1 1 2 3 4 5 Art A 07539 7 6 ...

Page 88: ...s 3 ITEM PART NUMBER DESCRIPTION QTY 1 204036 Label Precautions Arc Equip 1 2 831247PKD Label Mode Select Fab281 1 3 871081PKD Shroud Wrfdr A2281 1 4 377941 Guide Input 030 045 2R Plate 1 5 405377 Nut Wire Spool Hub 1 6 707289WBLKPKD Panel Internal A2281 1 1 2 3 4 5 Art A 07561 6 ...

Page 89: ...DESCRIPTION QTY 1 7977965PKD PCB Timer Fab210 251 A2281 PCB2 1 2 871003PKD Solenoid Assy 24VAC A2281 Y1 Y2 2 3 7978034PKD PCB Spool Gun Fab251 281 PCB3 1 4 7978050 PCB Control Fabricators PCB1 1 5 7976754PKD Terminal Block 12 Way 25A 1 1 2 2 5 3 4 Art A 07538 Refer to Appendix 7 for Terminal Block Wiring Information ...

Page 90: ... Plate 1 9 171374 Insulator Screw mtg 2R Plate 3 10 See Note 1 Screw PHCR M6 1x30mm STZP 3 11 171362 Clamp MIG gun 2R Plate 1 12 171380 Knob Clamp 2R Plate 1 13 870560PKD Gear Drive Roll 2R Plate 1 14 870733PKD Retainer Drive Gear 2R Plate 1 15 871001PKD Gear Idler Roll 2R Plate 1 16 406189 004 Bearing Idle Gear 2R 4R 1 17 377941 Guide Input 030 045 2R Plate 1 19 375655 Guide Output 2R Plate 1 20 ...

Page 91: ...fabricator 281 WELDING MACHINE Manual No 0 4880B 9 11 PARTS LIST 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 20 19 21 22 23 24 25 26 Art A 07562 ...

Page 92: ...tor 281 WELDING MACHINE PARTS LIST 9 12 Manual No 0 4880B 9 11 MIG Torch ITEM PART NUMBER DESCRIPTION QTY 1 43340 Weldskill MIG Gun 280A 15FT 1 Note Refer to Appendix 1 for individual components Art A 07560 1 ...

Page 93: ...th 25ft cable 300 Amp 60 ACCESSORIES Victor Regulator Flow Meter Mixed Gases 0781 2723 Medalist 1400 Series HRF Flow Meter Regulator Argon Argon CO2 mix gases Victor Regulator Flow Meter CO2 0781 2725 Medalist 1400 Series HRF Flow Meter Regulator CO2 gas TIPS 14 23 023 0 6mm 14 30 030 0 8mm 14 40 035 0 9mm 14 35 040 1 0mm 14 45 045 1 2mm 14 116 1 16 1 6mm NOZZLES 24A 38 3 8 9 5mm 24A 50 1 2 12 7mm...

Page 94: ...4B BLK 1D RED 1C RED SW1 W1 1B RED JE 1 JE 2 2 2A PNK 2A CB1 CB1 BURNBACK 100K TS1 M1 TEMP LED1 JA 2 JA 1 FABRICATOR 281 3 ORN 40B BLK 40A BLK 30 BRN 37A RED 32 WHT 33 BLU 34 BLU 35 WHT 36 GRY 39 RED 38A WHT 38 WHT 47 GRY 48 ORN 54 BLK 56 RED T1 TRANS 251US COIL 24 23 12 11 11 GRY T3 T4 12 12A BRN 18 17 6 5 12 BRN 16 16A WHT 22 21 10 9 16 WHT 13 13A VIO 14 13 2 1 13 VIO 17 17A BLK 16 15 4 3 17 BLK...

Page 95: ...BRN 53 WHT 57 VIO 55 BLK SWITCH POSITION 1 2 3 X X X X X X 1 2 6 5 4 3 8 9 7 11 10 12 SWITCH 3 FINE 5 6 4 X X 7 X 8 X X X X X X X X X X X X X 13 14 18 17 16 15 20 21 19 23 22 24 X X X X X X X X X X X1 1 X1 3 X1 2 X2 3 X2 2 X2 1 X3 4 X3 3 SHUNT PCB 4 704883 X1 6 X1 5 X1 4 X1 3 DIG METER X1 1 21 ORN 22 VIO 23 GRY 30A BRN 31B BLK POWER SOURCE WIREFEEDER A B C D E F G H I J J1 18 1SF 5A L1 68 ORN Art ...

Page 96: ...fabricator 281 APPENDIX A Manual No 0 4880B 30 VAC Art A 07520 APPENDIX 3 MAIN PCB CIRCUIT DIAGRAM ...

Page 97: ...fabricator 281 Manual No 0 4880B A APPENDIX DESCRIPTION FABRICATOR MAIN PCB 7978050 82 BENNING SREET WEST LEBANON NH 03784 USA Art A 07520_AB _ ...

Page 98: ...fabricator 281 APPENDIX A Manual No 0 4880B APPENDIX 4 SPOT TIMER CIRCUIT DIAGRAM Art A 07521 ...

Page 99: ...fabricator 281 Manual No 0 4880B A APPENDIX 82 BENNING SREET WEST LEBANON NH 03784 USA DESCRIPTION CODE DESIGN FABRICATOR SPOT TIMER 7977965 Art A 07521 ...

Page 100: ...3D LM324 Q4 BC337 40 14Vdc R14 22K R17 22K R21 22K R24 100K R23 22K 14Vdc D17 1N4004 D16 1N4004 C10 100n 9 10 8 U3C LM324 Q3 BC337 40 6 5 7 U3B LM324 2 3 1 4 11 U3A LM324 1 2 3 4 5 6 X3 CON6 SPOOL TRIG NORM TRIG 24VAC_1 Vin 3 ADJ 1 Vout 2 U1 LM317T D12 1N4004 D13 1N4004 D10 1N4004 D11 1N4004 C4 100n C1 470u 50V C5 22u 50V C3 100n R9 2K7 R10 270R 14Vdc D2 1N4004 24VAC_2 35Vdc D 9 Q 13 CLK 11 Q 12 R...

Page 101: ...dc 35Vdc D6 1N4148 D8 1N4148 D7 1N4148 D14 1N4004 R3 560R 1 2W Q2 BC337 40 R12 22K R5 22K Q1 BC337 40 K4 AZ945 K1 AZ945 K3 AZ945 K2 AZ945 C7 22u 50v 1 2 3 4 5 6 X1 CON6 1 2 3 4 5 6 X2 CON6 MOT COM MOT LOC MOT SPOOL GV COM GV LOC GV SPOOL POT COM POT LOC POT SPOOL TRIG N C TRIG D1 1N4004 1 2 J1 JUMPER Install jumper for use with MILLER spool gun which has no speed pot on the spool gun R1 560R 1 2W ...

Page 102: ...980 031 030 035 0 8 0 9mm 375980 001 375980 003 375980 010 030 035 045 0 8 0 9 1 2mm 375980 028 375980 029 035 0 9mm 375980 040 375980 032 035 045 3 64 0 9 1 2 1 2mm 375980 030 045 1 2mm 375980 002 375980 004 375980 092 375980 022 3 64 1 2mm 375980 011 375980 033 052 1 3mm 375980 090 375980 012 052 1 16 1 3 1 6mm 375980 017 375980 023 Notes 1 One Kit 375980 028 is supplied standard with each wire ...

Page 103: ...icator 281 Manual No 0 4880B A 11 APPENDIX APPENDIX 7 WIRE FEEDER TERMINAL BLOCK DIAGRAM 1 2 3 4 5 6 7 orange 31 gray 36 white 38 38A brown 30 white 32 32A gray 47 orange 48 FRONT OF WIRE FEEDER Art A 07599 ...

Page 104: ...fabricator 281 APPENDIX A 12 Manual No 0 4880B ...

Page 105: ......

Page 106: ...urchaser for service interruption The rem edies of the Purchaser set forth herein are exclusive and the liability of THERMADYNE 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 THERMADYNE whether arising out of contract negligence strict tort or...

Page 107: ...ROCESS INVERTER WELDING EQUIPMENT Parts Labor 160TS 300TS 400TS 185AC DC 200AC DC 300AC DC 400GTSW 400MST 300MST 400MSTP Original Main Power Magnetics 5 years 3 years Original Main Power Rectifiers Control P C Boards Power Switch Semi Conductors 3 years 3 years All Other Original Circuits and Components Including but not Limited to Relays Switches Contactors Solenoids Fans Electric Motors 1 year 1...

Page 108: ...54 727 8376 Oakville Ontario Canada Canada Customer Care Ph 1 905 827 4515 Fax 1 800 588 1714 tollfree Chorley United Kingdom Customer Care Ph 44 1257 261755 Fax 44 1257 224800 Milan Italy Customer Care Ph 39 0236546801 Fax 39 0236546840 Cikarang Indonesia Customer Care Ph 6221 8990 6095 Fax 6221 8990 6096 Rawang Malaysia Customer Care Ph 603 6092 2988 Fax 603 6092 1085 Melbourne Australia Austral...

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