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Thank you for selecting the R-Tech MIG321 Digital Inverter MIG Welder. The MIG321 Digital has many benefits over traditional MIG welders, including EASY SETUP, infinite power control and spool gun option for easy aluminium welding. We want you to take pride in operating our MIG321 Digital as much pride as we have taken in making this product for you.
Welding Capability – Duty Cycle The R-Tech MIG321 Digital is rated at 320 Amps at 35% duty cycle on a ten minute basis. If the duty cycle is exceeded a thermal protector will shut machine off until the machine cools.
Safety Precautions Read entire section before starting installation. Warning! Electric Shock can kill – Only qualified personnel should perform this installation. Turn off input power at the fuse box before working on this equipment. Do not touch electrically live parts. Always connect the machine to an earthed mains supply as per national recommended standards.
Electrical installation WARNING ELECTRIC SHOCK CAN KILL Electric Shock can kill – Only qualified personnel should perform this installation. Turn off input power at the fuse box before working on this equipment. Do not touch electrically live parts. Always connect the machine to an earthed mains supply as per national recommended standards.
Electrical installation cont. Input Connections Make sure the voltage, phase and frequency of input power is as specified on machine rating plate located at rear of machine. Have a qualified electrician provide suitable input power as per national electrical codes. Make sure machine is earthed / grounded.
Connections Front panel connections MIG mode + positive 7 pin socket for MIG mode - connect connector for earth spool on gun. earth lead (negative) lead for gasless flux when welding with cored wire only. GAS. MMA mode - connect MMA mode - connect electrode holder.
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Rear panel connections cont.. Gas connector & Extra earth connection On/Off Fuse for 240V aux output switch for water cooler 240V Aux output for water cooler Mains input cable - comes 3/8 BSP male connector with 2.5m cable fitted. for gas input Extra earth connection, used if you experience local interference (not normally used)
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Wire feed assembly, wire reel holder & gasless wire 1 - Wire reel retainer. Screw in to retain wire roll adaptor onto wire reel. 2 - Wire Feed Drive Assembly. To change roller size release retaining screw, remove roller and turn roller around and slide onto shaft making sure the right size groove is in line with wire and refit re- taining screw.
Front panel Digital Colour Screen with easy to navigate menu system EASY SET mode - pre-programmed weld settings MIG & MMA 1 - Wire feed speed - Turn to change setting in small steps, press and turn to change in larger steps 2 - Welding voltage - Turn to change setting in small steps, press and turn to change in larger steps 3 - SELECT button - Press to cycle through four welding modes 4 - Left arrow button - use to scroll left in menus...
MMA (STICK) in Manual mode MIG EASY MODE - With gas R-Tech Easy mode takes the guesswork out of MIG welding. You normally had to enter wire speed and welding voltage to weld on manual welders, we have done this for you.
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EASY SET MIG 0.6mm continued Once you have selected 0.6mm wire size and material thickness the suggested wire speed and voltage will be shown in the display, you are now ready to weld. If you want to fine tune the weld characteristics to suit your personal preference. You can trim the wire speed by 1 m/min by turning wire speed knob.
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MIG EASY MODE - Gasless wire (Flux cored) Press select button to Flux-Cored indicator. TO ENTER EASY MODE - PRESS EASY SET BUTTON ON FRONT PANEL Press left arrow to switch between 0.8mm,0.9mm & 1.0mm wire diameter, the selected size will flash Now press right arrow to switch between material thickness, the selected size will flash Once you have selected wire size and material thickness the suggested wire speed and voltage will be shown in the display, you are now ready to weld.
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MIG Manual mode In manual MIG mode you have full control of welding wire feed speed, welding voltage, 2T/4T trigger options, Burnback control and spool on gun operation. Use select button to select 95% ARG Mode, ensure EASY SET is off, the following screen will be shown. Set wire feed speed using left side knob, adjustable between 1.5 - 15 m/min.
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Burnback control Burnback is how long the welding power will continue after wire feed has stopped, this stops the wire from sticking to workpiece when weld finished, if Burnback is set too long you can experience wire burning back to tip. You can adjust Burnback by pressing left or right arrow buttons until Burnback is flashing, then use left knob to adjust from 0s to 2.0s For most applications a setting of 0.3s is advised.
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MMA (STICK) EASY R-Tech EASY SET mode takes the guesswork out of MMA welding. You normally had to enter required amperage to weld on manual welders, we have done this for you. You simply select the following from the easy to understand screen.
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MMA (STICK) EASY cont.. Note: When in MMA mode the welding terminals are constantly LIVE. Ensure electrode / electrode holder are not touching workpiece / earth when switching to MMA mode. MMA EASY SET SETTINGS. Electrode Type Electrode Size Material thickness 6013 2.5mm 1.5, 2, 3, 3, 4, 5mm...
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MMA (STICK) Manual mode Note: When in MMA mode the welding terminals are constantly LIVE. Ensure electrode / electrode holder are not touching workpiece / earth when switching to MMA mode. To enter MMA manual mode, use select button to move indicator to MMA then ensure EASY SET is turned off.
Troubleshooting No output - Display is not lit Check machine on/off switch is in the ‘on’ position Check Input power to machine Check plug wiring Check mains trip / fuses No output - Fan runs - Display is lit Check torch connections are secure and torch switch operation, try replacing MIG torch. No output –...
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