Lincoln Electric SQUARE WAVE TIG 255 SVM100-A User Manual
Square wave tig 255, Service manual, Svm100-a
Table of contents
Document Outline
- Master TOC
- Safety
- Section A Installation
- Section B Operation
- Section C Accessories
- Section D Maintenance
- Section E Theory of Operation
- Section F Troubleshooting & Repair
- Symptoms
- Major Physical or Electrical Damage is Evident.
- Machine is Dead - No Output - No Fan No Displays.
- Fan runs - Display and control panel dark. No output from machine in either Stick or TIG modes.
- The voltmeter reads “00” in Stick Mode, and there is no output from the machine when in the TIG 2-Step Mode.
- Machine does not respond (no gas flow, no high frequency and no open circuit voltage) when arc switch or amptrol is activated...
- 115VAC Receptacle not working properly (voltage is below 108VAC). Machine has welding output - fan is running.
- Machine regularly overheats - ther-mostat opens, PL1 (yellow light on front panel) glows. The fan runs but machine has no output
- Machine makes a very loud buzzing noise in DC Stick Mode, or in DC TIG Mode when the arc start or amptrol is pressed.
- There is no current draw from machine’s output studs. (The machine is not externally loaded).
- The ammeter displays a very high value (greater than 316 amps) when the machine is not loaded. Machine may have low or no out
- The yellow light (PL1) on the front panel is not lit.
- One or more keypad lights (LEDS) are dark and cannot be lit when their respective keys are pressed -machine is operable.
- The Beeper (Piezoelectric Buzzer) cannot be heard - machine operat-ing normally.
- The control panel displays cannot be read. The characters run, display only half characters, or random dots may appear on display
- The voltmeter always reads “00” . The machine output is normal.
- The control panel display background is dark instead of red. The machine operates normally.
- AC/DC Indicator on control panel display show AC when polarity switch is in the DC position, or vice versa - machine has output
- All red keypad LEDS are dark but the control panel display is operable. The machine has output.
- Machine output is intermittently lost. Gas flow and high frequency are also interrupted.
- Arc “Flutters” when TIG welding.
- Lack of penetration in AC TIG welding.
- Black areas along weld bead.
- Black areas along weld bead at or near end of weld.
- Machine has low output when in TIG 4-Step Mode.
- Weak high frequency - machine has normal welding output.
- The display shows zero amps, but indicates open circuit voltage (approximately 53V). The arc start switch or amptrol is not...
- High frequency “Spark” is present at tungsten electrode, but operator is unable to establish a welding arc. Machine has normal...
- No high frequency. Machine is in the TIG Mode and has normal output.
- No gas or water flow when arc start switch or amptrol is activated in the TIG Mode. Machine has output - fan runs. When toggl...
- Arc rectification when AC TIG weld-ing.
- There is no gas or water flow when the arc start switch or amptrol is activated in the TIG mode. The machine has output and the..
- Stick electrode “Blasts Off” when arc is struck.
- Cannot adjust AC Wave Balance when welding in the Stick Mode.
- Machine welds at a very low output regardless of the preset current setting - arc is stable.
- Variable or sluggish welding arc when welding in the Stick Mode.
- Section G Electrical Diagrams