Miller Electric CST 250 manual

Visit our website at www.MillerWelds.com Pro cesses Descrip ti on Stick (SMAW ) W elding OM -2237 206 035H July 2005 Arc Welding Power Source CST 250 TIG (GT A W) W elding[...]

Miller Electric manufactures a full line of welders and welding related equipment. For information on other quality Miller products, contact your local Miller distributor to receive the latest full line catalog or individual catalog sheets. T o locate your nearest distributor or service agency call 1-800-4-A-Miller , or visit us at www .MillerW eld[...]

T ABLE OF CONTENTS SECTION 1 − SAFETY PRECAUTIONS - READ BEFORE USING 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1. Symbol Usage 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2. Arc W elding Hazards 1 . . . . . . . . . . [...]

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OM-2237 Page 1 SECTION 1 − SAFETY PRECAUTIONS - READ BEFORE USING som _8/03 1-1. Symbol Usage Means W arning! W atch Out! There are possible hazards with this procedure! The possible hazards are shown in the adjoining symbols.  Marks a special safety message.  Means “Note”; not safety related. This group of symbols means W arning! Watch[...]

OM-2237 Page 2 Arc rays from the w elding process produce intense visible and invisible (ultraviolet and infrared) rays that can burn eyes and skin. Sparks fly of f from the weld. ARC RA YS can burn eyes and skin.  Wear a welding helmet fitted with a proper shade of filter to protect your face and eyes when welding or watching (see ANSI Z49.1 an[...]

OM-2237 Page 3 1-3. Additional Symbols For Installation, Operation, And Maintenance FIRE OR EXPLOSION hazard.  Do not install or place unit on, over , or near combustible surfaces.  Do not install unit near flammables.  Do not overload building wiring − be sure power supply system is properly sized, rated, and protected to handle this un[...]

OM-2237 Page 4 1-5. Principal Safety Standards Safety i n W elding, Cutting, and Allied Processes, ANSI Standard Z49.1, from American W elding Society , 550 N.W . LeJeune Rd, Miami FL 33126 (phone: 305-443-9353, website: www .aws.org). Recommended Safe Practices for the Preparation for W elding and Cut- ting of Containers and Piping , American Weld[...]

OM-2237 Page 5 SECTION 2 − CONSIGNES DE SÉCURITÉ − À LIRE A V ANT UTILISA TION som_fre 8/03 2-1. Signification des symboles Signifie « Mise en garde. Faire preuve de vigilance. » Cette procédure présente des risques identifiés par les symboles adjacents aux directives.  Identifie un message de sécurité particulier .  Signifie «[...]

OM-2237 Page 6 Le rayonnement de l’arc génère des rayons visibles et invisibles intenses (ultraviolets et infrarouges) suscep- tibles de causer des brûlures oculaires et cutanées. Des étincelles sont projetées pendant le soudage. LES RA YONS DE L ’ARC peuvent cau- ser des brûlures oculaires et cuta- nées.  Porter un masque de soudage[...]

OM-2237 Page 7 2-3. Autres symboles relatifs à l’installation, au fonctionnement et à l’entretien de l’appareil. Risque D’INCENDIE OU D’EXPLO- SION  Ne pas placer l’appareil sur une surface inflam- mable, ni au − dessus ou à proximité d’elle.  Ne pas installer l’appareil à proximité de produits inflammables.  Ne pas[...]

OM-2237 Page 8 2-4. Principales normes de sécurité Safety in W elding, Cutting, and Allied Processes, norme ANSI Z49.1, de l’American W elding Society , 550 N.W . LeJeune Rd, Miami FL 33126 (téléphone : (305) 443 − 9353, site Web : www .aws.org). Recommended Safe Practices for the Preparation for W elding and Cut- ting of Containers and Pip[...]

OM-2237 Page 9 SECTION 3 − INST ALLA TION 3-1. Specifications W elding Mode Input Power Rated Output W elding Amperage Range Maximum Open-Circuit V oltage Amperes Input At Rated Load Output, 50/60 Hz KV A KW Dimensions Net W eight Range V oltage 230 460 575 KV A KW Dimensions W e i g ht 3-Phase 250 A @ 30 VDC, 50 % Duty Cycle 5-250 A 77 VDC 30.5 [...]

OM-2237 Page 10 3-3. Stick (SMA W) V olt-Ampere Curves V olt-ampere curves show minimum and maximum voltage and amperage output capabilities of welding power source. Curves of other settings fall between curves shown. xx10 Stick V A Curves xx18 Stick V A Curve 0 10 20 30 40 50 60 70 80 90 100 0 5 0 100 150 200 250 300 350 DC AMPS DC VOL TS 100A SOF[...]

OM-2237 Page 1 1 3-4. TIG (GT A W) V olt-Ampere Curve V olt-ampere curves show minimum and maximum voltage and amperage output capabilities of welding power source. Curves of other settings fall between curves shown. TIG V A Curve 0 10 20 30 40 50 60 70 80 0 5 0 100 150 200 250 3 0 0 Amps Vo l t s Min 10A 50A 100A 150A 200A Max Ref. 206174[...]

OM-2237 Page 12 3-5. Selecting A Location 1 Line Disconnect Device Locate unit near correct input power supply .  Special installation may be required where gasoline or volatile liquids are present − see NEC Article 51 1 or CEC Section 20. Location And Airflow 1 18 in (460 mm) 18 in (460 mm) 803 080 18 in (457 mm) 13-1/2 in (343 mm) 7-1/2 in ([...]

OM-2237 Page 13 3-6. W eld Output T erminals And Selecting Cable Sizes* W eld Cable Size** and T otal Cable (Copper) Length in Weld Circuit Not Exceeding 100 ft (30 m) Or Less 150 ft (45 m) 200 ft (60 m) 250 ft (70 m) 300 ft (90 m) 350 ft (105 m) 400 ft (120 m) W eld Output T erminals Welding Amperes*** 10 − 60% Duty Cycle 60 − 100% Duty Cycle [...]

OM-2237 Page 14 3-7. TIG Lift-Arc t DCEN (Direct Current Electrode Negative) Connections Ref. 802 888 / Ref. 803 080 1 Positive (+) W eld Output T erminal Connect work lead to positive weld output terminal. 2 Negative ( − ) W eld Output T erminal Connect TIG torch to negative weld output terminal. 3 Gas Cylinder 4 Cylinder V alve Open valve sligh[...]

OM-2237 Page 15 3-8. Stick DCEP (Direct Current Electrode Positive) Connections Ref. 802 888 / Ref. 803 080 1 Negative ( − ) Weld Output T erminal Connect work lead to negative weld output terminal. 2 Positive (+) Weld Output T erminal Connect electrode holder to positive weld output terminal. 1 2 3-9. Electrical Service Guide  CAUTION: INCORR[...]

OM-2237 Page 16 3-10. Selecting 230 V olts AC Single/Three Phase Input V oltage 803 079 / 803 077  T urn Off welding power source, and disconnect input power before proceeding. Check input voltage available at site. 1 V oltage Selection V iew Window The input voltage that the power source is linked for appears in the V oltage Selection V iew Win[...]

OM-2237 Page 17 3-1 1. Selecting 460 - 575 V olts AC Three Phase Input V oltage 803 079 / 803 078  T urn Off welding power source, and disconnect input power before proceeding. Check input voltage available at site. 1 V oltage Selection V iew Window The input voltage that the power source is linked for appears in the V oltage Selection V iew Win[...]

OM-2237 Page 18  Disconnect and lockout/tag- out input power before connecting input conduc- tors from unit.  Have only qualified persons make this installation. See rating label on unit and check input voltage available at site. 1 Input And Grounding Conductors 2 Line Disconnect Device See Section 3-9. For three-phase operation:  Always c[...]

OM-2237 Page 19 SECTION 4 − OPERA TION 4-1. Controls 204 301 / 803 080 1 3 2 NOTE: Green on nameplate indicates a TIG function, Gray indicates a Stick function. 1 Power Switch Use switch to turn unit and indicator light On/Of f. 2 Output Indicator Light When unit is first energized this indicator light flashes several times and then illuminates c[...]

OM-2237 Page 20 4-2. Process Select Control 1 Process Select Control Rotate knob to select desired process. Lift-Arc  TIG - Normal open-circuit voltage is not present between the electrode and workpiece. A solid-state contactor does not energize until after the electrode touches the workpiece, preventing overheating, sticking, or contaminating t[...]

OM-2237 Page 21 4-3. Stick Start Procedure − Scratch Start T echnique With Stick selected, start arc as follows: 1 Electrode 2 W orkpiece 3 Arc Drag electrode across workpiece like striking a match; lift electrode slightly after touching work. If arc goes out electrode was lifted to high. If electrode sticks to workpiece, use a quick twist to fre[...]

OM-2237 Page 22 4-5. Amperage Control 1 AMP ADJUST (Amperage Control) Rotate knob clockwise to increase amperage (5-250 amps). 1 4-6. Remote 14 Receptacle Information This unit automatically senses when a remote control is connected to the remote 14 receptacle. After connecting a remote control, the unit will automatically adjust output control to [...]

OM-2237 Page 23 SECTION 5 − MAINTENANCE AND TROUBLESHOOTING 5-1. Routine Maintenance  Disconnect power before maintaining.  Maintain more often during severe conditions. 3 Months Replace unreadable labels. Clean and tighten weld terminals. Replace Damaged Gas Hose 3 Months Repair Or Replace Cracked Cables And Cords 6 Months Blow out inside.[...]

OM-2237 Page 24 5-3. T roubleshooting 1 2 1 Output LED (Blue) 2 High T emperature LED (Y ellow) 803 080 T rouble Possible Causes Remedy No weld output; unit completely inoperative. Line disconnect switch open. Place line disconnect switch in On position (see Section 3-12 ). Blown line fuse(s). Check and replace line fuse(s), if necessary , or reset[...]

OM-2237 Page 25 T rouble Remedy Possible Causes Erratic or improper weld output. W eld cable too small or defective. Use proper size and type of weld cable (see Section 3-6). Dirty or loose connections. Clean and tighten all weld connections (see Section 3-6). W andering arc Improper size tungsten. Use proper size tungsten (see Section 7). W orn or[...]

OM-2237 Page 26 SECTION 6 − ELECTRICAL DIAGRAMS Figure 6-1. Circuit Diagram 206 171-C[...]

OM-2237 Page 27 SECTION 7 − SELECTING AND PREP ARING TUNGSTEN ELECTRODE gtaw 7/97 For additional information, see your distributor for a handbook on the Gas T ungst en Ar c Welding (G T AW) process .Wear clean gloves to prevent contamination of tungsten electrode. NOTE 7-1. Selecting T ungsten Electrode Amperage Range - Gas T ype ♦ - Polarity E[...]

OM-2237 Page 28 7-3. Preparing T ungsten For AC Or DC Electrode Negative (DCEN) Welding Ref. S-0161 / Ref. S-0162 1 T ungsten Electrode 2 T apered End Grind end of tungsten on fine grit, hard abrasive wheel before weld- ing. Do not use wheel for other jobs or tungsten can become contami- nated causing lower weld quality . 3 Ideal Tungsten Preparati[...]

OM-2237 Page 29 Notes[...]

OM-2237 Page 30 SECTION 8 − P ARTS LIST  Hardware is common and not available unless listed. 803 157-B 8 12 13 20 21 25 23 7 2 4 22 3 24 10 5 1 9 6 15 19 14 14 15 18 17 19 28 26 11 27 16 Figure 8-1. Main Assembly[...]

OM-2237 Page 31 Figure 8-1. Main Assembly Item No. Part No. Description Quantity 1 205758 P ANEL,FRONT W/CMPNT 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 205780 P ANEL,REAR W/CMPNT 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [...]

OM-2237 Page 32  Hardware is common and not available unless listed. 803 158 14 9 13 12 15 3 17 4 2 18 1 19 8 20 4 6 5 22 21 10 16 11 7 7 23 Figure 8-2. Panel, Front w/Components 907 1 16 907052 Figure 8-2. Panel, Front w/Components Diagram marking Item No. Part No. Description Quantity Model 1 194242 P ANEL,FRONT/REAR 1 1 . . . . . . . . . . . [...]

OM-2237 Page 33  Hardware is common and not available unless listed. 803 161-B 7 6 1 2 7 3 4 5 Figure 8-3. Panel, Rear w/Components Figure 8-3. Panel, Rear w/Components Item No. Part No. Description Quantity 1 194242 P ANEL,FRONT/REAR 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [...]

OM-2237 Page 34  Hardware is common and not available unless listed. 803 163-B 13 3 1 10 9 11 12 14 8 7 8 2 5 4 6 8 16 15 Figure 8-4. Magnetics Subassembly Diagram marking Item No. Part No. Description Quantity Figure 8-4. Magnetics Subassembly 1 206063 P ANEL,PLENUM 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .[...]

OM-2237 Page 35  Hardware is common and not available unless listed. 803 159-C 4 8 1 9 6 7 3 2 12 13 11 10 12 5 13 Figure 8-5. Heat Sink Assembly , Output Diode Diagram marking Item No. Part No. Description Quantity Figure 8-5. Heat Sink Assembly , Output Diode 1 205916 HEA T SINK,DIODE OUTPUT 1 . . . . . . . . . . . . . . . . . . . . . . . . . [...]

OM-2237 Page 36  Hardware is common and not available unless listed. 803 160 2 3 1 5 4 8 7 6 Figure 8-6. Base Assembly Diagram marking Item No. Part No. Description Quantity Figure 8-6. Base Assembly 1 206089 BASE, 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . [...]

OM-2237 Page 37  Hardware is common and not available unless listed. Ref. 803 162 1 2 3 Figure 8-7. Heat Sink Assembly , Input Diagram marking Item No. Part No. Description Quantit y Figure 8-7. Heat Sink Assembly , Input 1 205915 HEA T SINK,IGBT/INPUT RECTIFIER MODULE 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .[...]

Notes[...]

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