OM-2803C January 1999 144 084C Processes With An Inverter Power Source: TIG (GTAW) Welding Stick (SMAW) Welding Description Programmable Precision DC TIG Controller Intellitig 4 Visit our website at www.millerwelds.com
From Miller to You Thank you and congratulations on choosing Miller. Now you can get the job done and get it done right. We know you don t have time to do it any other way. That s why when Niels Miller first started building arc welders in 1929, he made sure his products offered long-lasting value and superior quality. Like you, his customers couldn t afford anything less. Miller products had to be more than the best they could be. They had to be the best you could buy. Today, the people that build and sell Miller products continue the tradition. They re just as committed to providing equipment and service that meets the high standards of quality and value established in 1929. This Owner s Manual is designed to help you get the most out of your Miller products. Please take time to read the Safety precautions. They will help you protect yourself against potential hazards on the worksite. We ve made installation and operation quick and easy. With Miller you can count on years of reliable service with proper maintenance. And if for some reason the unit needs repair, there s a Troubleshooting section that will help you Miller is the first welding equipment manufacturer in the U.S.A. to be registered to the ISO 9001 Quality System Standard. figure out what the problem is. The parts list will then help you to decide which exact part you may need to fix the problem. Warranty and service information for your particular model are also provided. 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. To locate your nearest distributor or service agency call 1-800-4-A-Miller, or visit us at www.millerwelds.com on the web. Working as hard as you do every power source from Miller is backed by the most hassle-free warranty in the business. Miller offers a Technical Manual which provides more detailed service and parts information for your unit. To obtain a Technical Manual, contact your local distributor. Your distributor can also supply you with Welding Process Manuals such as SMAW, GTAW, GMAW, and GMAW-P.
TABLE OF CONTENTS The following terms are used interchangeably throughout this manual: TIG = GTAW Stick = SMAW SECTION 1 SAFETY PRECAUTIONS - READ BEFORE USING............................ 1 1-1. Symbol Usage................................................................ 1 1-2. Arc Welding Hazards.......................................................... 1 1-3. Additional Symbols for Installation, Operation, and Maintenance...................... 3 1-4. Principal Safety Standards..................................................... 3 1-5. EMF Information.............................................................. 4 SECTION 2 SPECIFICATIONS......................................................... 5 2-1. Control Unit.................................................................. 5 SECTION 3 INSTALLATION........................................................... 6 3-1. Typical Process Connections................................................... 6 3-2. Setting DIP Switch SW1....................................................... 7 3-3. Installing Gas Supply.......................................................... 8 3-4. Connecting Remote Pendant.................................................... 9 3-5. Remote 14 Receptacle Information And Connections............................... 9 3-6. Function Of User Relays 1 And 2 (Use Is Optional)................................. 10 3-7. User Relay Connections....................................................... 11 3-8. Weld Input And Output Connections.............................................. 12 3-9. Connecting Input Power........................................................ 13 SECTION 4 OPERATION............................................................. 15 4-1. Controls..................................................................... 15 4-2. Safety Equipment............................................................. 15 4-3. Work Clamp.................................................................. 16 4-4. Digital Display................................................................ 16 4-5. Program/Run/Reset Keyed Switch............................................... 16 4-6. Mode Selector Switch.......................................................... 17 4-7. Parameter Select Push Button.................................................. 17 4-8. Right/Increase Push Button..................................................... 17 4-9. Left/Decrease Push Button..................................................... 18 4-10. Purge Push Button............................................................ 18 4-11. Gas Control And Flow Rate Meter............................................... 18 4-12. Power Switch................................................................ 19 4-13. Remote Pendant.............................................................. 19 4-14. Shielding Gas................................................................ 19 SECTION 5 MAINTENANCE & TROUBLESHOOTING.................................... 20 5-1. Routine Maintenance.......................................................... 20 5-2. Overload Protection........................................................... 21 5-3. Adjusting Spark Gaps......................................................... 21 5-4. Troubleshooting.............................................................. 22 SECTION 6 INTRODUCTION TO PROGRAMMING....................................... 23 6-1. Introduction.................................................................. 23 6-2. Modes Of Operation........................................................... 23 SECTION 7 PROGRAMMING......................................................... 27 7-1. General..................................................................... 27 7-2. Automatic Mode.............................................................. 28 7-3. Semi-Automatic Mode......................................................... 32 7-4. Manual GTAW Mode.......................................................... 36 7-5. SMAW Mode................................................................. 39 7-6. Editing A Program............................................................. 40 7-7. Dry Run Feature.............................................................. 40 7-8. Stop Watch Feature........................................................... 40 7-9. Linking Programs............................................................. 40 7-10. Combining Programs.......................................................... 41 SECTION 8 SEQUENCE OF OPERATION............................................... 43 8-1. Gas Tungsten Arc Welding (GTAW) In The Automatic Mode......................... 43 8-2. Gas Tungsten Arc Welding (GTAW) In The Semi-Automatic Modes................... 43 8-3. Gas Tungsten Arc Welding (GTAW) In The Manual Mode............................ 46 8-4. Shielded Metal Arc Welding (SMAW)............................................. 47 8-5. Executing Linked Programs..................................................... 47 8-6. Executing Combined Programs.................................................. 47 8-7. Shutting Down................................................................ 47 SECTION 9 DIAGNOSTICS........................................................... 48 9-1. Introduction.................................................................. 48 9-2. Diagnostics Program.......................................................... 48 SECTION 10 ELECTRICAL DIAGRAMS................................................ 58 SECTION 11 HIGH FREQUENCY...................................................... 62 SECTION 12 TUNGSTEN ELECTRODE................................................ 64 12-1. Selecting Tungsten Electrode................................................... 64 12-2. Preparing Tungsten........................................................... 65 SECTION 13 PARTS LIST............................................................ 66 WARRANTY
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. 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 Welding Hazards The symbols shown below are used throughout this manual to call attention to and identify possible hazards. When you see the symbol, watch out, and follow the related instructions to avoid the hazard. The safety information given below is only a summary of the more complete safety information found in the Safety Standards listed in Section 1-4. Read and follow all Safety Standards. Only qualified persons should install, operate, maintain, and repair this unit. During operation, keep everybody, especially children, away. ELECTRIC SHOCK can kill. Touching live electrical parts can cause fatal shocks or severe burns. The electrode and work circuit is electrically live whenever the output is on. The input power circuit and machine internal circuits are also live when power is on. In semiautomatic or automatic wire welding, the wire, wire reel, drive roll housing, and all metal parts touching the welding wire are electrically live. Incorrectly installed or improperly grounded equipment is a hazard. Do not touch live electrical parts. Wear dry, hole-free insulating gloves and body protection. Insulate yourself from work and ground using dry insulating mats or covers big enough to prevent any physical contact with the work or ground. Do not use AC output in damp areas, if movement is confined, or if there is a danger of falling. Use AC output ONLY if required for the welding process. If AC output is required, use remote output control if present on unit. Disconnect input power or stop engine before installing or servicing this equipment. Lockout/tagout input power according to OSHA 29 CFR 1910.147 (see Safety Standards). Properly install and ground this equipment according to its Owner s Manual and national, state, and local codes. Always verify the supply ground check and be sure that input power cord ground wire is properly connected to ground terminal in disconnect box or that cord plug is connected to a properly grounded receptacle outlet. When making input connections, attach proper grounding conductor first double-check connections. Frequently inspect input power cord for damage or bare wiring replace cord immediately if damaged bare wiring can kill. Turn off all equipment when not in use. Do not use worn, damaged, undersized, or poorly spliced cables. Do not drape cables over your body. If earth grounding of the workpiece is required, ground it directly with a separate cable do not use work clamp or work cable. Do not touch electrode if you are in contact with the work, ground, or another electrode from a different machine. Use only well-maintained equipment. Repair or replace damaged parts at once. Maintain unit according to manual. Wear a safety harness if working above floor level. Keep all panels and covers securely in place. Clamp work cable with good metal-to-metal contact to workpiece or worktable as near the weld as practical. Insulate work clamp when not connected to workpiece to prevent contact with any metal object. Do not connect more than one electrode or work cable to any single weld output terminal. SIGNIFICANT DC VOLTAGE exists after removal of input power on inverters. Turn Off inverter, disconnect input power, and discharge input capacitors according to instructions in Maintenance Section before touching any parts. FUMES AND GASES can be hazardous. Welding produces fumes and gases. Breathing these fumes and gases can be hazardous to your health. Keep your head out of the fumes. Do not breathe the fumes. If inside, ventilate the area and/or use exhaust at the arc to remove welding fumes and gases. If ventilation is poor, use an approved air-supplied respirator. Read the Material Safety Data Sheets (MSDSs) and the manufacturer s instructions for metals, consumables, coatings, cleaners, and degreasers. Work in a confined space only if it is well ventilated, or while wearing an air-supplied respirator. Always have a trained watchperson nearby. Welding fumes and gases can displace air and lower the oxygen level causing injury or death. Be sure the breathing air is safe. Do not weld in locations near degreasing, cleaning, or spraying operations. The heat and rays of the arc can react with vapors to form highly toxic and irritating gases. Do not weld on coated metals, such as galvanized, lead, or cadmium plated steel, unless the coating is removed from the weld area, the area is well ventilated, and if necessary, while wearing an air-supplied respirator. The coatings and any metals containing these elements can give off toxic fumes if welded. OM-2803 Page 1
ARC RAYS can burn eyes and skin. BUILDUP OF GAS can injure or kill. 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. Shut off shielding gas supply when not in use. Always ventilate confined spaces or use approved air-supplied respirator. 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). Wear approved safety glasses with side shields under your helmet. Use protective screens or barriers to protect others from flash and glare; warn others not to watch the arc. Wear protective clothing made from durable, flame-resistant material (leather and wool) and foot protection. HOT PARTS can cause severe burns. Do not touch hot parts bare handed. Allow cooling period before working on gun or torch. WELDING can cause fire or explosion. Welding on closed containers, such as tanks, drums, or pipes, can cause them to blow up. Sparks can fly off from the welding arc. The flying sparks, hot workpiece, and hot equipment can cause fires and burns. Accidental contact of electrode to metal objects can cause sparks, explosion, overheating, or fire. Check and be sure the area is safe before doing any welding. Protect yourself and others from flying sparks and hot metal. Do not weld where flying sparks can strike flammable material. Remove all flammables within 35 ft (10.7 m) of the welding arc. If this is not possible, tightly cover them with approved covers. Be alert that welding sparks and hot materials from welding can easily go through small cracks and openings to adjacent areas. Watch for fire, and keep a fire extinguisher nearby. Be aware that welding on a ceiling, floor, bulkhead, or partition can cause fire on the hidden side. Do not weld on closed containers such as tanks, drums, or pipes, unless they are properly prepared according to AWS F4.1 (see Safety Standards). Connect work cable to the work as close to the welding area as practical to prevent welding current from traveling long, possibly unknown paths and causing electric shock and fire hazards. Do not use welder to thaw frozen pipes. Remove stick electrode from holder or cut off welding wire at contact tip when not in use. Wear oil-free protective garments such as leather gloves, heavy shirt, cuffless trousers, high shoes, and a cap. Remove any combustibles, such as a butane lighter or matches, from your person before doing any welding. FLYING METAL can injure eyes. Welding, chipping, wire brushing, and grinding cause sparks and flying metal. As welds cool, they can throw off slag. Wear approved safety glasses with side shields even under your welding helmet. MAGNETIC FIELDS can affect pacemakers. Pacemaker wearers keep away. Wearers should consult their doctor before going near arc welding, gouging, or spot welding operations. NOISE can damage hearing. Noise from some processes or equipment can damage hearing. Wear approved ear protection if noise level is high. CYLINDERS can explode if damaged. Shielding gas cylinders contain gas under high pressure. If damaged, a cylinder can explode. Since gas cylinders are normally part of the welding process, be sure to treat them carefully. Protect compressed gas cylinders from excessive heat, mechanical shocks, slag, open flames, sparks, and arcs. Install cylinders in an upright position by securing to a stationary support or cylinder rack to prevent falling or tipping. Keep cylinders away from any welding or other electrical circuits. Never drape a welding torch over a gas cylinder. Never allow a welding electrode to touch any cylinder. Never weld on a pressurized cylinder explosion will result. Use only correct shielding gas cylinders, regulators, hoses, and fittings designed for the specific application; maintain them and associated parts in good condition. Turn face away from valve outlet when opening cylinder valve. Keep protective cap in place over valve except when cylinder is in use or connected for use. Read and follow instructions on compressed gas cylinders, associated equipment, and CGA publication P-1 listed in Safety Standards. OM-2803 Page 2
1-3. Additional Symbols For Installation, Operation, And Maintenance FIRE OR EXPLOSION hazard. MOVING PARTS can cause injury. Do not install or place unit on, over, or near combustible surfaces. Do not install unit near flammables. Keep away from moving parts such as fans. Keep all doors, panels, covers, and guards closed and securely in place. Do not overload building wiring be sure power supply system is properly sized, rated, and protected to handle this unit. FALLING UNIT can cause injury. Use lifting eye to lift unit only, NOT running gear, gas cylinders, or any other accessories. Use equipment of adequate capacity to lift and support unit. If using lift forks to move unit, be sure forks are long enough to extend beyond opposite side of unit. OVERUSE can cause OVERHEATING Allow cooling period; follow rated duty cycle. Reduce current or reduce duty cycle before starting to weld again. Do not block or filter airflow to unit. H.F. RADIATION can cause interference. High-frequency (H.F.) can interfere with radio navigation, safety services, computers, and communications equipment. Have only qualified persons familiar with electronic equipment perform this installation. The user is responsible for having a qualified electrician promptly correct any interference problem resulting from the installation. If notified by the FCC about interference, stop using the equipment at once. Have the installation regularly checked and maintained. Keep high-frequency source doors and panels tightly shut, keep spark gaps at correct setting, and use grounding and shielding to minimize the possibility of interference. STATIC (ESD) can damage PC boards. Put on grounded wrist strap BEFORE handling boards or parts. Use proper static-proof bags and boxes to store, move, or ship PC boards. MOVING PARTS can cause injury. Keep away from moving parts. Keep away from pinch points such as drive rolls. WELDING WIRE can cause injury. Do not press gun trigger until instructed to do so. Do not point gun toward any part of the body, other people, or any metal when threading welding wire. ARC WELDING can cause interference. Electromagnetic energy can interfere with sensitive electronic equipment such as computers and computer-driven equipment such as robots. Be sure all equipment in the welding area is electromagnetically compatible. To reduce possible interference, keep weld cables as short as possible, close together, and down low, such as on the floor. Locate welding operation 100 meters from any sensitive electronic equipment. Be sure this welding machine is installed and grounded according to this manual. If interference still occurs, the user must take extra measures such as moving the welding machine, using shielded cables, using line filters, or shielding the work area. 1-4. Principal Safety Standards Safety in Welding and Cutting, ANSI Standard Z49.1, from American Welding Society, 550 N.W. LeJeune Rd, Miami FL 33126 Safety and Health Standards, OSHA 29 CFR 1910, from Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. Recommended Safe Practices for the Preparation for Welding and Cutting of Containers That Have Held Hazardous Substances, American Welding Society Standard AWS F4.1, from American Welding Society, 550 N.W. LeJeune Rd, Miami, FL 33126 National Electrical Code, NFPA Standard 70, from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. Safe Handling of Compressed Gases in Cylinders, CGA Pamphlet P-1, from Compressed Gas Association, 1235 Jefferson Davis Highway, Suite 501, Arlington, VA 22202. Code for Safety in Welding and Cutting, CSA Standard W117.2, from Canadian Standards Association, Standards Sales, 178 Rexdale Boulevard, Rexdale, Ontario, Canada M9W 1R3. Safe Practices For Occupation And Educational Eye And Face Protection, ANSI Standard Z87.1, from American National Standards Institute, 1430 Broadway, New York, NY 10018. Cutting And Welding Processes, NFPA Standard 51B, from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. OM-2803 Page 3
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. However, after examining more than 500 studies spanning 17 years of research, a special blue ribbon committee of the National Research Council concluded that: The body of evidence, in the committee s judgment, has not demonstrated that exposure to powerfrequency electric and magnetic fields is a human-health hazard. However, studies are still going forth and evidence continues to be examined. Until the final conclusions of the research are reached, you may wish to minimize your exposure to electromagnetic fields when welding or cutting. 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 cables around your body. 4. Keep welding power source and cables as far away from operator as practical. 5. Connect work clamp to workpiece as close to the weld as possible. About Pacemakers: Pacemaker wearers consult your doctor first. If cleared by your doctor, then following the above procedures is recommended. OM-2803 Page 4
SECTION 2 SPECIFICATIONS 2-1. Control Unit Specification Welding Processes Welding Circuit Rating Type Of Input Power Overall Dimensions Weight Description Gas Tungsten Arc (GTAW), Shielded Metal Arc (SMAW) Welding 250 Amperes At 100% Duty Cycle When Used With 115 Volts: 115 Volts AC Single-Phase 50/60 Hz, 1.0 Amperes When Used With 230 Volts: 230 Volts AC Single-Phase 50/60 Hz, 0.5 Amperes Height: 9-1/8 in (232 mm); Width: 9-1/2 in (241 mm); Length: 19-1/4 in (489 mm) Net: 30 lb (13.6 kg); Ship: 37 lb (16.8 kg) OM-2803 Page 5
SECTION 3 INSTALLATION WARNING HIGH-FREQUENCY RADIATION can interfere with radio navigation, safety services, computers, and communications equipment. Have only qualified person familiar with electronic equipment perform this installation. Read and follow entire Section 11 for proper location and installation requirements for high-frequency equipment before installing unit. swarn13.1 4/93 3-1. Typical Process Connections For GTAW Welding 1 Welding Power Source 2 Gas Cylinder 3 Control Unit 4 Remote Pendant Control 5 Torch 6 Work Clamp 2 4 1 7 Foot Control 8 Electrode Holder 3 5 1 6 7 For SMAW Welding 3 8 6 7 ST-800 505 / ST-800 504 OM-2803 Page 6
3-2. Setting DIP Switch SW1 WARNING ELECTRIC SHOCK can kill Do not touch live electrical parts. Turn Off welding power source and control unit, and disconnect input power before setting DIP switches. STATIC ELECTRICITY can damage parts on circuit boards. Put on grounded wrist strap BEFORE handling boards or parts. fwarn2.1* 9/91 / fwarn5.1* 9/91 Set DIP switch positions as follows: 1 2 1 Front Panel 2 Retaining Screw Loosen retaining screw, and open hinged front panel. 3 Microprocessor Board PC1 4 DIP Switch SW1 Factory default settings shown. To set a position, depress the end near the desired choice. 5 Positions 1 And 2 Positions 5 and 6 are not used. In Automatic and Semi-Automatic 1, weld amperage can be adjusted up or down during weld using remote pendant. Define amperage adjustment range limits by setting positions 1 and 2 according to table. 6 Position 3 3 8 7 6 5 1 2 3 4 5 6 7 8 Off = On Use position 3 to select whether pulses are defined as time or frequency values. Set Off to define as frequency. Set On to define as time. 7 Position 4 Set Off to run diagnostics program. Set On to stop diagnostics program, and for all other operations. 8 Positions 7 And 8 Set 7 and 8 according to table to select Semi-Automatic Modes 1 thru 5. Close front panel and tighten retaining screw after setting SW1. 4 Position 1 On On Off Off Position 2 On Off On Off Defined Amperage Adjustment Limit ±5 Amperes ±10 Amperes ±20 Amperes ±40 Amperes Position 7 On On Off Off On Position 8 On Off On Off On Defined Semi-Automatic Mode *1 2 3 4 *5 Tools Needed: *Semi-Automatic 1 mode is defined when remote Stop switch is connected. Semi- Automatic 5 mode is defined when remote Stop switch is not connected. ST-146 842 / ST-800 506 OM-2803 Page 7
3-3. Installing Gas Supply WARNING CYLINDERS can explode if damaged. Keep cylinders away from welding and other electrical circuits. Never touch cylinder with welding electrode. Always secure cylinder to running gear, wall, or other stationary support. BUILDUP OF SHIELDING GAS can harm health or kill. Shut off shielding gas supply when not in use. warn4.1 9/91 NOTE Allowable pressure range for shielding gas input is 30-50 psi (207 to 345 kpa). 1 Obtain gas cylinder and chain to running gear, wall, or other stationary support so cylinder cannot fall and break off valve. 1 Cap 2 Cylinder Valve 6 2 Remove cap, stand to side of valve, and open valve slightly. Gas flow blows dust and dirt from valve. Close valve. 3 Cylinder 4 Regulator/Flowmeter 8 7 5 4 Argon Gas 3 Install so face is vertical. 5 Gas Hose Connection Fitting has 5/8-18 right-hand threads. Obtain and install gas hose. 6 Flow Adjust Typical flow rate is 20 cfh (cubic feet per hour). 7 Gas In Fitting 8 Gas Out Fitting The Gas In and Gas Out fittings have 5/8-18 right-hand threads. Obtain proper size, type, and length hose and make connections as follows: Connect hose from shielding gas supply regulator/flowmeter to Gas In fitting. Connect shielding gas hose from torch to Gas Out fitting. To Torch Tools Needed: 5/8, 1-1/8 in ssb3.3* 6/93 ST-146 841-A / Ref. ST-158 697-A / Ref. ST-140 732 OM-2803 Page 8
3-4. Connecting Remote Pendant 2 REMOTE 4 3 1 1 Remote Pendant 2 Remote 4 Receptacle RC2 3 Keyway 4 Plug A B D C 5 4 5 Threaded Collar Use receptacle to connect supplied remote pendant. User-wired controls equivalent to remote control are also connected to this receptacle. To connect to this receptacle, align keyway, insert plug, and tighten threaded collar. Socket Information: A Normally closed contact with socket C opens when pendant Stop button is pressed. B Normally open contact with socket C closes when pendant Decrease button is pressed. C +24 volts dc. D Normally open contact with socket C closes when pendant Start/Increase button is pressed. sb7.1* 8/92 ST-146 841-A / Ref. ST-140 732 / ST-146 839 / Ref. S-0446-A 3-5. Remote 14 Receptacle Information And Connections 1 Remote 14 Receptacle RC3 1 REMOTE 14 A J K B I C L N H D M G E F 2 4 3 2 Keyway 3 Plug 4 Threaded Collar To connect to this receptacle, align keyway, insert plug, and tighten threaded collar. Socket Information: Remote Contactor A +24 volts dc. B Contact closure to pin A completes +24 volts dc contactor control circuit. Remote Amperage/Voltage Control C Command reference; +10 volts dc. D Control circuit common. E Input command signal (potentiometer wiper or 0 to +10 volts dc). The remaining sockets are not used. sb7.1* 8/92 ST-146 841-A / Ref. ST-140 732 / Ref. S-0004-A / S-0750 OM-2803 Page 9
3-6. Function Of User Relays 1 And 2 (Use Is Optional) User Relay 1 User relays 1 and 2 can be used to control external devices, such as fixtures. Preflow Initial Slope Initial Current Weld/Peak Current Final Slope Final Current Postflow When enabled, relay 1 changes states according to programmed time delay values in the Automatic, Semi-Automatic 1, and Semi-Automatic 5 modes. In the remaining modes, relay 1 is not functional. The relay is also not functional if disabled. 1 Start Delay Range Preflow 1 Initial Slope Initial Current Weld/Peak Current Final Slope Final Current 2 Postflow The programmed start delay value determines how long after the Start/ Increase push button is pressed user relay 1 will energize. The range of acceptable values is 0.0 to 120.0 seconds. In order to function properly, the start delay value must not delay energization beyond the end of weld/peak current. 2 Stop Delay Range The programmed stop delay value determines how long after weld/ peak current ends user relay 1 will deenergize. The range is 0.0 to 120.0 seconds. The stop delay time cannot delay deenergization of user relay 1 beyond the end of postflow. User Relay 2 Initial Slope Initial Current Preflow 1 Weld/Peak Current Final Slope Final Current 2 Postflow 1 Relay 2 Energizes 2 Relay 2 Deenergizes Relay 2 energizes when initial current starts if an arc is detected, and deenergizes when final current ends. If an arc is not detected, relay 2 does not energize. In Automatic mode and Semi-Automatic modes 1 and 5, relay 2 changes state only if the relay is enabled during programming. In Semi-Automatic modes 2, 3, and 4, relay 2 changes state whether enabled or not. Ref. SB-139 983 OM-2803 Page 10
3-7. User Relay Connections WARNING ELECTRIC SHOCK can kill Do not touch live electrical parts. Turn Off welding power source and control unit, and disconnect input power before making user relay connections. STATIC ELECTRICITY can damage parts on circuit boards. Put on grounded wrist strap BEFORE handling boards or parts. fwarn2.1* 9/91 / fwarn5.1* 9/91 When making connections to user relay contacts, use #28 to #18 AWG solid or stranded insulated wire. Do not strip insulation from end of wire before making connections. The contacts are rated at 5 amperes, 230 volts each. Open front panel and remove top from unit. 1 Strain Relief Connector 1 3 4 6 5 Loosen strain relief and insert wires. Route wires to desired terminals (see table). 2 Interface Board PC3 3 Terminal Assembly (Six Total) 4 Lever Up 5 Wire Insertion Hole 6 Lever Down For each connection, lift terminal lever, insert wire, and push terminal lever down to locked position. Tighten strain relief when all connections are made. Reinstall top, and close front panel. Connect leads to external devices. To avoid high frequency interference, route leads away from weld cables. 2 Connection On Terminal Strip 1 2 3 4 5 6 Function User Relay #2 N.O. Contact User Relay #2 Common User Relay #2 N.C. Contact User Relay #1 N.O. Contact User Relay #1 Common User Relay #1 N.C. Contact N.O. = normally open N.C. = normally closed ST-146 841-A / ST-800 506 / Ref. SB-139 983 OM-2803 Page 11
3-8. Weld Input And Output Connections WARNING ELECTRIC SHOCK can kill. Do not touch live electrical parts. Turn Off control unit and welding power source, and disconnect input power before making connections. swarn12.1* 2/92 Input Plug Connections Output Receptacle Connections For GTAW Welding 3 Torch 4 Positive (+) Negative ( ) Positive (+) Negative ( ) 1 2 1 Positive Input Plug Connect weld cable from positive (+) terminal on welding power source to Positive Input plug. 2 Negative Input Plug Connect weld cable from negative ( ) terminal on welding power source to Negative Input plug. GTAW DC Electrode Negative/ Straight Polarity (DCEN) 3 Torch Receptacle Connect torch cable. 4 Positive (+) Receptacle Connect one end of work cable, connect remaining end to workpiece. For DC Electrode Positive (DCEP), reverse cable connections. SMAW DC Electrode Positive/ Reverse Polarity (DCEP) 4 Positive (+) Receptacle Connect electrode holder cable. 5 Negative ( ) Receptacle Connect one end of work cable, connect remaining end to workpiece. For DC Electrode Negative (DCEN), reverse cable connections. Output Receptacle Connections For SMAW Welding Torch 4 Positive (+) Negative ( ) 5 Tools Needed: 3/4 in ssb2.2 11/92 Ref. S-0752 / ST-146 841-A OM-2803 Page 12
3-9. Connecting Input Power WARNING ELECTRIC SHOCK can kill. Do not touch live electrical parts. Turn Off control unit and welding power source, and disconnect input power before inspecting or installing. Have only qualified persons install unit. Installation must meet National Electrical Code and all other codes. swarn3.1* 2/93 A. To Power Source Receptacle Information And Connections 1 2 J A I K B H N L C G M D F E 1 To Power Source Receptacle RC1 2 Keyway 3 Plug 4 Threaded Collar Connections to this receptacle require an interconnecting cord that is suitable for the welding power source being used with the control unit. To connect to this receptacle, align keyway, insert plug, and tighten threaded collar. See Section 3-9B for instructions on connecting the remaining end of the interconnecting cord to the welding power source. 3 4 Socket Information: A Provides connection to program-controlled relay contact internal to control unit; contact makes connection with relay contact connected to pin B to energize welding power source. B Contact closure to pin A completes contactor control circuit. D Control circuit common with respect to pin E. E Provides 0 to +10 volt dc command signal with respect to pin D. G 115 volts ac circuit common; also connected to welding power source chassis. I Up to 1.0 amperes of 115 volts ac, 60 Hz, with respect to socket G (circuit common). K Machine chassis (circuit common). The remaining sockets are not used. sb7.1* 8/92 ST-146 841-A / Ref. S-0004-A / S-0750 OM-2803 Page 13
B. Interconnecting Cord Connections 1 Depending on welding power source used, select and obtain interconnecting cord and make connections as follows: 1 Interconnecting Cord With 14-Pin Plug Only 2 Connect to Remote 14 receptacle on welding power source. Align keyway, insert plug, and tighten threaded collar. 2 Interconnecting Cord With 14-Pin Plug And 115 Volt AC Plug Connect 14-pin plug to Remote 14 receptacle on welding power source. Align keyway, insert plug, and tighten threaded collar. Insert 115 volt ac plug into 115 volt ac duplex receptacle. 3 3 Interconnecting Cord With 5-Pin Plug And 115 Volt AC Plug Connect 5-pin plug to Remote 5 receptacle on welding power source. Align keyway, insert plug, and tighten threaded collar. Insert 115 volt ac plug into 115 volt ac duplex receptacle. ST-800 288 C. Changing Jumper Links For 230 Volts Operation 230 VOLTS 1 115 VOLTS 2 S-072 212-A 3 For applications requiring 230 volts input power, proceed as follows: Open front panel, and remove top cover. Route suitable customer-supplied input power cable thru strain relief on rear panel. Disconnect existing leads 1 and 2 (circuit common) from Power switch S1, and connect new cable leads to same S1 terminals. Change jumper links positions as follows: 1 Input Voltage Label 2 Input Terminal Board TE1 3 Input Voltage Jumper Links Move links as shown on label. Reinstall top cover, and close front panel. Tools Needed: 1/4 in ST-800 506 OM-2803 Page 14
SECTION 4 OPERATION WARNING ELECTRIC SHOCK can kill. Always wear dry insulating gloves. Insulate yourself from work and ground. Do not touch live electrical parts. Keep all panels and covers securely in place. FUMES AND GASES can be hazardous to your health. Keep your head out of the fumes. Ventilate area, or use breathing device. Read Material Safety Data Sheets (MSDSs) and manufacturer s instructions for material used. WELDING can cause fire or explosion. Do not weld near flammable material. Watch for fire; keep extinguisher nearby. Do not locate unit over combustible surfaces. Do not weld on closed containers. Allow work and equipment to cool before handling. ARC RAYS can burn eyes and skin; NOISE can damage hearing. Wear welding helmet with correct shade of filter. Wear correct eye, ear, and body protection. MOVING PARTS can cause injury. Keep away from moving parts. Keep all doors, panels, covers, and guards closed and securely in place. MAGNETIC FIELDS FROM HIGH CUR- RENTS can affect pacemaker operation. Pacemaker wearers keep away. Wearers should consult their doctor before going near arc welding, gouging, or spot welding operations. See Safety Precautions at beginning of manual for basic welding safety information. swarn6.1 10/91 4-1. Controls 1 2 1 Power Switch (On Rear Panel) 11 10 9 3 4 5 2 Digital Display 3 Right/Increase Push Button 4 Parameter Select Push Button 5 Mode Switch 6 Program/Run/Reset Keyed Switch 7 Left/Decrease Push Button 8 Purge Push Button 9 Gas Control 10 Gas Flow Rate Meter 11 Remote Pendant 8 7 6 ST-800 503 / Ref. ST-146 839 4-2. Safety Equipment 1 2 3 1 Insulating Gloves 2 Safety Glasses With Side Shields 3 Welding Helmet Wear dry insulating gloves, safety glasses with side shields, and a welding helmet with a correct shade of filter (see ANSI Z49.1). sb3.1 10/91 OM-2803 Page 15
4-3. Work Clamp Tools Needed: 1 1 Work Clamp Connect work clamp to a clean, paint-free location on workpiece, as close to weld area as possible. Use wire brush or sandpaper to clean metal at weld joint area. Use chipping hammer to remove slag after welding. sb4.1 2/93 4-4. Digital Display 1 1 Digital Display Depending on the mode and programmed options, the digital display either shows the steps in the welding program or weld output. Program Displays Use display to enter and read values. If weld program steps are shown during operation, the programmed time values decrease as process time runs out. Weld Output Metering If selected during programming, the digital display shows weld output amperage and voltage values as the weld program is carried out. Weld output metering is always active when a Manual GTAW or SMAW program is carried out. If the voltage value exceeds 99.9 volts, the display shows OVR. Ref. ST-139 983 4-5. Program/Run/Reset Keyed Switch 1 1 Program/Run/Reset Keyed Switch Use switch for selecting these three functions: Program Use to enter, change, and/or execute a program. Run Use to execute a program only. Key can be removed to prevent unauthorized access to program. Reset Use before switching between Run/ Program positions when unit is On. For example, use Program position to enter program, move to Reset momentarily, and move to Run to execute program. Remove key if desired. If changing program, move to Reset momentarily before moving back to Program. OM-2803 Page 16
4-6. Mode Selector Switch 1 Mode Selector Switch Use switch to select weld mode. 1 4-7. Parameter Select Push Button 1 1 Parameter Select Push Button Use switch for these functions: When display contains multiple parameters, pressing switch selects each parameter in sequence. When a parameter is selected, it flashes and is ready to have a value entered. Pressing switch while the last parameter in a display is selected deselects that parameter without selecting the next parameter. Pressing switch when a display shows an either/or option toggles the displayed option between the two choices. 4-8. Right/Increase Push Button To zero a parameter value, select parameter and press Right/Increase and Left/Decrease switches at the same time. 1 1 Right/Increase Push Button Use switch for these functions: Pressing switch while a parameter is selected increases that parameter value. Press and hold switch to rapidly increase the value. Pressing switch without a parameter being selected scrolls to next display in the sequence. OM-2803 Page 17
4-9. Left/Decrease Push Button To zero a parameter value, select parameter and press Right/Increase and Left/Decrease switches at the same time. 1 1 Left/Decrease Push Button Use switch for these functions: Pressing switch while a parameter is selected decreases that parameter value. Press and hold switch to rapidly decrease the value. Pressing switch without a parameter being selected scrolls to previous display in the sequence. 4-10. Purge Push Button 1 1 Purge Push Button Use switch to momentarily energize gas valve and purge air from torch shielding gas line, and to allow shielding gas regulator and flow rate meter to be adjusted without energizing the welding circuit. Switch is only active when the repeating displays are shown. 4-11. Gas Control And Flow Rate Meter 1 Gas Control Use control to adjust flow of shielding gas. 2 Shielding Gas Flow Rate Meter Meter indicates flow rate of shielding gas. Meter shows cubic feet per hour and has a range of 0-60 feet per hour with Argon shielding gas. 2 1 OM-2803 Page 18
4-12. Power Switch 1 Power Switch Use switch to turn power to control unit On and Off. 1 ST-146 841-A / Ref. ST-140 732 4-13. Remote Pendant 2 3 4 1 1 Remote Pendant Use for remote operation in the Automatic and Semi-Automatic modes only. Connect to Remote 4 receptacle (see Section 3-4). 2 Stop Push Button 3 Start/Increase Push Button 4 Decrease Push Button Push button functions are described in operating instructions for Automatic and Semi-Automatic modes. Ref. ST-146 839 4-14. Shielding Gas WARNING BUILDUP OF SHIELDING GAS can harm health or kill. Shut off shielding gas supply when not in use. warn1.1 9/91 1 Shielding Gas Cylinder 2 1 3 4 2 Valve 3 Torch Switch 4 Foot Control Open valve on cylinder just before welding. OR Torch trigger or foot control turns weld output and gas flow on and off. Close valve on cylinder when finished welding. sb5.2* 2/92 S-0621-C / ST-159 059 OM-2803 Page 19
SECTION 5 MAINTENANCE & TROUBLESHOOTING WARNING ELECTRIC SHOCK can kill. Do not touch live electrical parts. Turn Off welding power source and control unit, and disconnect input power before inspecting, maintaining, or servicing. HOT PARTS can cause severe burns. Allow cooling period before maintaining or servicing. MOVING PARTS can cause injury. Keep away from moving parts. STATIC ELECTRICITY can damage parts on circuit boards. Put on grounded wrist strap BEFORE handling boards or parts. Maintenance to be performed only by qualified persons. swarn8.1* 2/93 5-1. Routine Maintenance 3 Months Turn Off all power before maintaining. 3 Months Replace Unreadable Labels Tape Or Replace Cracked Cables Gas Hose Replace Cracked Parts Remote Cords Torch Cable 6 Months Clean And Tighten Weld Connections OR Blow Out Or Vacuum Inside ST-146 842 OM-2803 Page 20
5-2. Overload Protection WARNING READ SAFETY BLOCKS at start of Section 5 before proceeding. 1 Tools Needed: 1/4 in Turn Off welding power source and control unit, and disconnect input power. Open front panel, and remove top cover. 1 Fuse F1 F1 protects the control circuitry from overload. If F1 opens, the control unit shuts down. Check fuse and replace if needed. See Parts List for fuse rating. Use proper tool when removing fuse. Reinstall top cover, and close front panel. ST-800 506 / Ref. ST-146 844-A 5-3. Adjusting Spark Gaps WARNING READ SAFETY BLOCKS at start of Section 5 before proceeding. 4 Turn Off welding power source and control unit, and disconnect input power. 2 3 1 5 1 1 Arc Starter Board PC8 Open front panel and remove top cover. Remove middle panel. Locate spark gaps on PC8. 2 Tungsten End Of Point Do not clean or dress tungsten. Replace entire circuit board if tungsten end disappears. 3 Spark Gap Normal spark gap is 0.028 in (0.711 mm). If spark gap is okay, reinstall middle panel and top cover. Close front cover. If adjustment is needed, continue as follows: 4 Retaining Screw Loosen screw. Place feeler gauge of proper thickness in spark gap. 5 Pressure Point Apply slight pressure at point until gauge is held firmly in gap. Tighten retaining screw. Tools Needed: 1/4 in Reinstall middle panel and top cover. Close front panel. 0.028 in (0.711 mm) Ref. ST- 146 844-A / S-0658 OM-2803 Page 21
5-4. Troubleshooting WARNING ELECTRIC SHOCK can kill. Do not touch live electrical parts. Turn Off welding power source and control unit, and disconnect input power before inspecting, maintaining, or servicing. HOT PARTS can cause severe burns. Allow cooling period before maintaining or servicing. MOVING PARTS can cause injury. Keep away from moving parts. STATIC ELECTRICITY can damage parts on circuit boards. Put on grounded wrist strap BEFORE handling boards or parts. Troubleshooting to be performed only by qualified persons. swarn8.1* 2/93 Trouble Remedy Section Display dark; unit completely inoperative. Be sure control unit and welding power source Power switches are On. Check for proper input power connections. 3-9 Check fuse F1 and replace if needed. 5-2 4-12 Erratic or improper weld output. Tighten all welding cable connections. 3-8 Check for proper size and type of cable. Check for proper input and output connections. 3-8 Replace electrode. 12-1, 12-2 No high frequency; difficulty in establishing GTAW arc. Be sure electrode holder cable is not close to any grounded metal. 11 Check cables and torch for cracked insulation or bad connections. Repair or replace necessary parts. Check to make sure high frequency is enabled in program. 7-4 Check spark gaps and adjust if necessary. 5-3 11 Remote Pendant Control completely inoperative or working erratically. Check connections to Remote 4 receptacle. 3-4 Check to make sure mode selector switch is in Automatic or Semi- Automatic. 4-6 Wandering arc; poor control of arc direction. Reduce gas flow rate. 4-11 Select proper size tungsten. 12-1 Properly prepare tungsten. 12-2 Tungsten electrode oxidizing and not remaining bright after conclusion of weld. Shield weld zone from drafts. Increase postflow time. Check and tighten all gas fittings. Water in torch. Refer to torch Owner s Manual for part(s) requiring replacement, and repair torch as necessary. OM-2803 Page 22
SECTION 6 INTRODUCTION TO PROGRAMMING 6-1. Introduction A. General Programs are created when parameters are defined in a series of displays. Up to four programs can be created per mode, for a total of sixteen programs. Programs can be run individually, or can be linked or combined to run in a user-defined sequence. When properly connected to the welding power source, this unit provides high frequency or scratch starting, preflow timing, start current level control and timing, initial current level control and timing, initial slope timing, final slope timing, final current level control and timing, postflow timing, and amperage control of weld/peak current for either a pulsing or nonpulsing weld current. Pulsing controls include on/off selection, pulse peak level control and timing, background current level control and timing, and pulse frequency and average current calculations. This unit also provides manual gas flow control. B. Weld Sequence Initial Slope Initial Current Preflow Weld/Peak Current Final Slope Final Current Postflow Final Slope: The ramping down of weld/peak current to the programmed final current level. Final Current: The end current level just before the arc is extinguished. Postflow: The period during which shielding gas flows after the arc has been extinguished. 6-2. Modes Of Operation The control unit has four modes of operation: Automatic, Semi-Automatic, Manual GTAW, and SMAW. In abbreviated form, the modes function as follows: A. Automatic Mode (Figure 6-2) A program that is created in the Automatic mode uses programmed information to control each step of the weld sequence. Pressing the Start/Increase push button begins the sequence, with no more input required from the operator. The operator has the ability to increase or decrease the weld amperage during weld/peak current within the defined amperage adjustment limits (see Section 3-2). This change does not affect the programmed values. Pressing the Stop push button at any time during the weld sequence halts program execution and sends the sequence directly to postflow. Figure 6-1. Weld Sequence Ref. SB-139 983 In order to effectively use the control unit, it is necessary to understand the weld sequence as it is shown in Figure 6-1. In most cases, some form of this weld sequence is used in programming the control. Which steps are programmable and what initiates each step varies from mode to mode. The steps in the weld sequence are defined as follows: Preflow: The period during which shielding gas flows before an arc is established. Start Level (Not Shown): A current level that can be programmed to ease arc starting. Initial Current: The beginning maintained current level. Initial Slope: The ramping of the initial current up to the programmed weld/peak current level. Weld/Peak Current: The programmed weld current level (divided into peak and background current levels when pulsing is enabled). Initial Slope Initial Current Preflow A Weld/Peak Current Final Slope Final Current Postflow A: Momentary closure of Start/Increase push button begins sequence. 1. Preflow: Time programmed/volume set by gas meter. 2. Start Level (Not Shown): Time & level programmed. 3. Initial Current: Time & level programmed. 4. Initial Slope: Time programmed/slope calculated by control unit. 5. Weld/Peak Current: Time & level programmed. 6. Final Slope: Time programmed/slope calculated by control unit. 7. Final Current: Time & level programmed. 8. Postflow: Time programmed/volume set by gas meter. Stop push button functions throughout sequence. Weld/peak current can be increased and/or decreased during welding. Ref. SB-139 983 Figure 6-2. Automatic Mode Sequence OM-2803 Page 23