OM-154 501S March 1999 Processes Gas Metal Arc (MIG) Welding ® Flux Cored Arc (FCAW) Welding Description Arc Welding Power Source And Wire Feeder MW250 For Warranty Claims And Technical Support, Contact: Milweld Inc., National Distributor P.O.
TABLE OF CONTENTS The following term is used interchangeably throughout this manual: MIG=GTAW WARNING This product, when used for welding or cutting, produces fumes or gases which contain chemicals known to the State of California to cause birth defects and, in some cases, cancer. (California Health & Safety Code Section 25249.5 et seq.) OM-154 501S SECTION 1 − SAFETY PRECAUTIONS - READ BEFORE USING . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1. Symbol Usage . . . . . . . . . . . . . . . .
SECTION 1 − SAFETY PRECAUTIONS - READ BEFORE USING som _nd_5/97 1-1. Symbol Usage Means Warning! Watch Out! There are possible hazards with this procedure! The possible hazards are shown in the adjoining symbols. Y Marks a special safety message. . Means “Note”; not safety related. This group of symbols means Warning! Watch Out! possible ELECTRIC SHOCK, MOVING PARTS, and HOT PARTS hazards. Consult symbols and related instructions below for necessary actions to avoid the hazards. 1-2.
ARC RAYS can burn eyes and skin. Arc rays from the welding process produce intense visible and invisible (ultraviolet and infrared) rays that can burn eyes and skin. Sparks fly off from the weld. D 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 and Z87.1 listed in Safety Standards). D Wear approved safety glasses with side shields under your helmet.
1-3. Additional Symbols For Installation, Operation, And Maintenance FIRE OR EXPLOSION hazard. MOVING PARTS can cause injury. D Do not install or place unit on, over, or near combustible surfaces. D Do not install unit near flammables. D Do not overload building wiring − be sure power supply system is properly sized, rated, and protected to handle this unit. D Keep away from moving parts such as fans. D Keep all doors, panels, covers, and guards closed and securely in place.
1-5. EMF Information Considerations About Welding And The Effects Of Low Frequency Electric And Magnetic Fields Welding current, as it flows through welding cables, will cause electromagnetic fields. There has been and still is some concern about such fields.
SECTION 2 − SPECIFICATIONS 2-1. Specifications Specifications Description Type Of Output Direct Current/Constant Voltage (DC/CV) Rated Weld Output 200 Amperes, 28 Volts DC, 60% Duty Cycle (See Section 2-2) Type Of Input Power Single-Phase; 60 Hz; At 200 Or 230 Volts AC Input Amperes At Rated Output 46 A At 200 V, 40 A At 230 V Maximum Input Amperes While Idling 1.2 A At 200 V, 1 A At 230 V KVA/KW Used At Rated Output 9.5 kVA/8.3 kW Maximum KVA/KW Used While Idling 0.24 kVA/0.17 kW Max.
2-2. Duty Cycle And Overheating Duty Cycle is percentage of 10 minutes that unit can weld at rated load without overheating. UNIT If unit overheats, thermostat(s) opens, output stops, and cooling fan runs. Wait fifteen minutes for unit to cool. Reduce amperage or duty cycle before welding. 60% Duty Cycle At 200 Amperes Y Exceeding duty cycle can damage unit and void warranty.
3-2. Installing Gas Supply 1 Cylinder Bracket 2 S-Hook Crimp between small hole in bracket and chain. 1 3 Chain 4 Snap Crimp onto open end of chain. Obtain gas cylinder and chain to running gear. 2 3 4 11 To Gas Regulator/ Flowmeter 5 Cap 6 Cylinder Valve Remove cap, stand to side of valve, and open valve slightly. Gas flow blows dust and dirt from valve. Close valve. 7 Cylinder 8 Regulator/Flowmeter Install so face is vertical.
3-3. Gun Polarity Connections 1 Polarity Changeover Label 2 Wire Drive Assembly 3 Positive (+) Output Terminal 4 Negative (−) Output Terminal Always read and follow wire manufacturer’s recommended polarity. Shown As Shipped − Set For Electrode Positive (DCEP) For Solid Steel Or Aluminum Wires (GMAW Process). 5 Wire Drive Assembly Lead To Positive (+) Output Terminal Circuit Breaker CB1 (see Section 5-2). Close door.
3-6. Positioning Jumper Links 200 VOLTS 2 3 Check input voltage available at site. 1 Jumper Links Access Door Open door. 230 VOLTS 2 3 Jumper Link Label Input Voltage Jumper Link Move jumper link to match input voltage. Close and secure access door. 1 S-153 980 Close side door. Tools Needed: 3/8 in Ref.
3-7. Connecting Input Power Have only qualified persons make this installation. 1 3 4 3 1 Line Disconnect Device Of Proper Rating 2 230 Volts AC Wall Receptacle 3 Input Conductors 4 Grounding Conductor Select size and length using 3-5. Conductor rating must comply with national, state, and local electrical codes. 3 2 Install and connect grounding conductor and input conductors in conduit or equivalent between wall receptacle and deenergized line disconnect device.
3-8. Installing Wire Spool And Adjusting Hub Tension 1 Wire Spool 2 Gun Contact Tip If necessary, cut welding wire off at contact tip, and retract wire onto spool and secure. 1 2 3 Retaining Ring 4 Compression Spring Remove ring and pull off spool. Compression spring is used with 8 in (200 mm) spools. 5 Hub 6 Hub Pin Slide spool onto hub so wire feeds off bottom. Turn spool until hub pin fits hole in back of spool. Reinstall retaining ring.
3-9. Threading Welding Wire 1 Tools Needed: 4 2 3 5 Welding Wire 3 Inlet Wire Guide 4 Pressure Adjustment Knob 5 Drive Roll 6 Outlet Wire Guide 7 Gun Conduit Cable Lay gun cable out straight. 7 1 Wire Spool 2 6 4 in (102 mm) 6 in (150 mm) Open pressure assembly. Pull and hold wire; cut off end. Push wire thru guides into gun; continue to hold wire. Tighten Close and tighten pressure assembly, and let go of wire. Remove gun nozzle and contact tip. Turn On.
SECTION 4 − OPERATION 4-1. Front Panel Controls 1 Wire Speed Control Use control to set wire feed speed. 2 1 2 Voltage Control Use control and Voltage Range Selector (see 4-2) to set arc voltage. Step 6 of Low range and Step 1 of High range overlap. 3 Pilot Light 4 Power Switch Use switch to turn unit On and Off. The pilot light comes on when unit is turned on. 5 Work Clamp Use wire brush or sandpaper to clean metal at weld joint area.
4-2. Center Baffle Controls 1 DO NOT SWITCH UNDER LOAD WIRE MODE FULL 1 2 Wire Mode Switch For better control of wire speed use Low position when wire speed is between 90 and 670 ipm. Use Full position when wire speed is between 150 ipm and 1030 ipm. 2 Voltage Range Selector Place switch in desired position. See inside rear cover for settings. LOW VOLTAGE RANGE 20−30V HIGH 10−20V LOW Ref.
SECTION 5 − MAINTENANCE & TROUBLESHOOTING 5-1. Routine Maintenance . Maintain more often Y Disconnect power before maintaining. during severe conditions. 3 Months Clean And Tighten Weld Terminals Repair Or Replace Cracked Cables And Cords Replace Damaged Or Unreadable Labels 6 Months Blow Out Or Vacuum Inside Remove drive roll and carrier. Apply light coat of oil or grease to drive motor shaft. 5-2. Circuit Breaker CB1 1 1 Circuit Breaker CB1 If CB1 opens, wire feeding stops.
5-3. Fuses F1 And F2 Turn Off unit and disconnect input power. 1 Fuse F1 (See Parts List For Rating) F1 protects the 115 volts ac winding of transformer T1. If F1 opens, all weld output stops and pilot light PL1 goes out. 2 2 Fuse F2 (See Parts List For Rating) F2 protects the 24 volts ac winding of transformer T1. If F2 opens, all weld output stops. 1 Ref. ST-800 928-B 5-4. Changing Drive Rolls And Wire Inlet Guide 1 2 Loosen screw. Slide tip as close to drive rolls as possible without touching.
5-6. Troubleshooting Welding Trouble No weld output; wire does not feed. Remedy Check input power connections (see Section 3-7). Reset circuit breaker CB1 (see Section 5-2). Replace fuse F1 and/or F2 (see Section 5-3). Replace building line fuse or reset circuit breaker if open (see Section 3-7). Secure gun trigger plug in receptacle or repair leads (see Section 3-4). Thermostat TP1 open (overheating). Allow fan to run; the thermostat will close when the unit has cooled (see Section 2-2).
SECTION 6 − ELECTRICAL DIAGRAM SB-173 544-E Figure 6-1.
Notes OM-154 501 Page 19
SECTION 7 − PARTS LIST 11 9 2(Fig. 7−2) 1 12 10 8 7 3 6 5 13 4 14 15 16 17 22 18 21 19 ST-155 610-E 20 Figure 7-1. Main Assembly NOTE: All items indented by a dot(s) are included with the item listed directly above. Item Part No. No.
1 2 3 4 5 10 6 11 7 12 13 8 30 9 14 29 28 15 16 19 20 17 Fig.7−3 − 27 18 21 26 22 25 24 23 ST-155 609-E Figure 7-2. Baffle w/Components (Fig 7-1 Item 2) NOTE: All items indented by a dot(s) are included with the item listed directly above. Item Part No. No. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 058 427 085 980 605 941 186 437 057 971 057 745 186 435 186 436 177 307 174 812 186 998 083 147 082 902 185 643 184 584 185 642 Description Retaining Ring Nut Flat Washer Spring, .
See Table 6-1 Drive Roll & Wire Guide Kits. . Hardware is common and 13 9 not available unless listed. 8 10 11 7 14 12 6 5 4 3 16 2 26 25 1 23 24 22 15 16 21 20 19 18 ST-148 529-H Figure 7-3. Wire Drive And Gears (Fig 7-2 Item 27) Item Part No. No. Description 1 2 3 4 5 6 7 8 9 10 11 12 13 Screw, .250-20 x 1.
Table 7-1. Drive Roll And Wire Guide Kits IMPORTANT: Base selection of drive rolls upon the following recommended usages: 1. V-Grooved rolls for hard wire. 2. U- Grooved rolls for soft and soft shelled cored wires. 3. U-Cogged rolls for extremely soft shelled wires (usually hard surfacing types). 4. V-Knurled rolls for hard shelled cored wires. 5. Drive roll types may be mixed to suit particular requirements (example: V-Knurled roll in combination with U-Grooved). Wire Diameter Drive Roll Part No.
Warranty Effective January 1, 1999 (Equipment with a serial number preface of “KK” or newer) This limited warranty supersedes all previous manufacturers warranties and is exclusive with no other guarantees or warranties expressed or implied. LIMITED WARRANTY − Subject to the terms and conditions below, warrants to its original retail purchaser that new equipment sold after the effective date of this limited warranty is free of defects in material and workmanship at the time it is shipped from factory.
Owner’s Record Please complete and retain with your personal records. Model Name Serial/Style Number Purchase Date (Date which equipment was delivered to original customer.) Distributor Address City State Zip Resources Available Always provide Model Name and Serial/Style Number.
