logo elektroda
logo elektroda
X
logo elektroda
Advanced Search
logo elektroda

Magnum MIG 200MMA IGBT Welder Feeds Wire Continuously, Display Not Working

daniel9541 17220 12
ADVERTISEMENT
Treść została przetłumaczona polish » english Zobacz oryginalną wersję tematu
Report a violation of the law
| New topic
  • #1 16818451
    daniel9541
    Level 2  
    Posts: 2
    Rate: 5
    Hello. I have a migum welder Magnum mig 200mma igbt. The problem is that the welder went on all the time after the warranty expired immediately popsula. He feeds the wire all the time. After disconnecting the "pistol" the roller is still spinning. In addition, the display on the welder does not work. After unscrewing the housing, you can see how it warms, I think ... transformer and 2 white plates that after being turned on, are hot and stink all the time. What could be the reason for the fault? What could be the cost of repair ??

    The welder looks like this
    Magnum MIG 200MMA IGBT Welder Feeds Wire Continuously, Display Not Working
    Photo plate
    Magnum MIG 200MMA IGBT Welder Feeds Wire Continuously, Display Not Working
  • ADVERTISEMENT
  • #2 16818600
    bearq
    Level 39  
    Posts: 4878
    Help: 414
    Rate: 1598
    Rather no fairies on the forum, give the welder to some service that will repair it if it is profitable at all. That this Magnum broke down right after the warranty is normal, such a company.
  • ADVERTISEMENT
  • #3 16818703
    daniel9541
    Level 2  
    Posts: 2
    Rate: 5
    I'm not looking for fairies in the forum. I'm just asking others if they had the case or they know it. .
  • #4 16818890
    bearq
    Level 39  
    Posts: 4878
    Help: 414
    Rate: 1598
    Even if someone knows each other, no one can give you an answer through the forum, looking only at the center of the welder. Something has apparently been damaged and to diagnose it you should have such a system in front of you, make the appropriate measurements and only then you can comment on the damage or possible repair costs.
  • ADVERTISEMENT
  • #5 16821788
    stasiekb100
    Level 31  
    Posts: 2031
    Help: 114
    Rate: 445
    I have 280 with this case. I'll let you know how to fix it.

    Added after 17 [hours] 28 [minutes]:

    Diagnosis - damaged motor drive transistor and motor brake transistor. I don't know any other elements yet, I'll finish it.

    Added after 19 [hours] 30 [minutes]:

    The 15 V zener diode in the motor drive transistor gate control circuit has failed. The transistor went into linear operation and burned out, I replaced the transistor and the zener diode.
  • ADVERTISEMENT
  • #6 17095239
    xavi77
    Level 11  
    Posts: 31
    Help: 1
    Rate: 13
    Hello.

    And can you ask for where are these elements and what to use?
  • #7 17099538
    stasiekb100
    Level 31  
    Posts: 2031
    Help: 114
    Rate: 445
    Magnum MIG 200MMA IGBT Welder Feeds Wire Continuously, Display Not Working
  • #8 17111459
    xavi77
    Level 11  
    Posts: 31
    Help: 1
    Rate: 13
    Hello.

    I replaced the igbt9z24 transistor, 15v zener diode and additionally a q5 8050 transistor, the welding machine fired normally, the display lit up, the engine did not run. After switching on the feed, the problem returned, i.e. the display is off, the engine is running all the time and something is popping up.
    Attachments:
    • MIG-MMA160_200-250_-1.pdf (119.27 KB) You must be logged in to download this attachment.
  • #9 17113003
    stasiekb100
    Level 31  
    Posts: 2031
    Help: 114
    Rate: 445
    And the brake transistor colleague checked?
  • #10 17114594
    xavi77
    Level 11  
    Posts: 31
    Help: 1
    Rate: 13
    I did not check the order, but if something is broken there, it causes such a symptom.
  • #11 17136804
    xavi77
    Level 11  
    Posts: 31
    Help: 1
    Rate: 13
    Hello

    I also replaced vt1 irfz 44 now the symptom is that the welding machine turns on, the display is lit, the engine is not working, but when you press the handle, listen to the gas valve while the engine is not turned on.
  • #12 17188955
    feniks_
    Level 11  
    Posts: 116
    Help: 1
    Rate: 38
    And the 7805 and 7812 stabilizers are ok? Surely it hasn't damaged or burned irf9z24 again?
  • #13 17189748
    xavi77
    Level 11  
    Posts: 31
    Help: 1
    Rate: 13
    Motor drive transistors listed. The welder works. Thanks for the help.
| New topic
Report a violation of the law

Topic summary

✨ The discussion revolves around a Magnum MIG 200MMA IGBT welder that experiences continuous wire feeding and a non-functional display after the warranty period. Users suggest that the issue may stem from damaged components, specifically the motor drive transistor and the brake transistor. One participant diagnosed a failed 15V zener diode in the motor drive circuit, which led to the replacement of the transistor and diode. Another user reported replacing several components, including the IGBT transistor and stabilizers, but continued to face issues with the welder's operation. The consensus is that a thorough diagnosis and potential component replacement are necessary for repair.
Generated by the language model.

FAQ

TL;DR: Reported fixes replace 2 transistors and a 15 V zener; “motor drive and brake transistors were damaged.” [Elektroda, stasiekb100, post #16821788]

Why it matters: This FAQ helps owners diagnose and fix continuous wire feed and dead display on Magnum MIG 200MMA/280MMA IGBT units.

Quick Facts

What causes my Magnum MIG 200MMA to feed wire continuously and show no display?

Failures in the wire-feed control path are typical. Users reported a burned motor drive transistor, a failed motor brake transistor, and a shorted 15 V zener in the gate circuit. These faults force the motor on and can drop logic rails, blanking the display. Replacing those parts restored operation. “Motor drive and brake transistors were damaged.” [Elektroda, stasiekb100, post #16821788]

How do I quickly diagnose the continuous wire-feed fault?

Check for constant voltage at the motor terminals with the trigger disconnected. Inspect the motor drive transistor, the brake transistor, and the 15 V zener in the gate network. If the zener has failed, the drive device may run linearly and overheat. Replace failed parts before power testing again. [Elektroda, stasiekb100, post #16821788]

Where are the relevant components on the control board?

A contributor shared a marked board image showing the motor drive section and associated parts. Use that diagram to locate the motor MOSFETs, brake transistor area, and protection zener. Match silkscreen designators onsite. Print the image for bench reference during probing and replacement. [Elektroda, stasiekb100, post #17099538]

What parts have users actually replaced to fix this issue?

Reported replacements include the motor drive transistor, the motor brake transistor, and a 15 V zener diode tied to the drive gate. After replacement, machines returned to normal behavior, stopping the motor and restoring the display. One user confirmed success after these swaps. [Elektroda, stasiekb100, post #16821788]

Which additional components should I test if the fault returns after partial repair?

Test VT1 IRFZ44 (motor drive MOSFET) and Q5 8050. Verify the torch trigger path and observe the gas valve click during trigger presses. A user saw the valve actuate but the motor stay off until further parts were replaced. This indicates remaining faults around the motor drive. [Elektroda, xavi77, post #17136804]

Do I need to check the 5 V and 12 V regulators?

Yes. Measure the 7805 and 7812 outputs under load. Low or unstable rails can blank the display and upset motor control. Also recheck the IRF9Z24/“igbt9z24” device if present in your board revision, as it may fail again when rails misbehave. [Elektroda, feniks_, post #17188955]

What is the motor brake transistor and why does it matter?

The brake transistor momentarily shorts the motor leads after feed to stop the wire quickly. If it fails short, the motor can behave erratically or stress the drive transistor. If it fails open, stopping becomes sluggish and control loops misread speed. Replace it with the correct rated part. [Elektroda, stasiekb100, post #16821788]

What is a zener diode in the gate circuit and how can it fail?

The zener clamps gate voltage to protect the MOSFET. A failed 15 V zener can force the MOSFET into linear mode, overheating it and causing continuous feed. Replace the zener with the same value and check the gate resistor network for collateral damage. [Elektroda, stasiekb100, post #16821788]

How can I tell if my repair worked before full reassembly?

Power the unit with the torch unplugged. The display should light, the feed motor should be stopped, and no overheating smell should appear. Then connect the torch and tap the trigger to confirm momentary feed. One user reported full recovery after transistor replacements. [Elektroda, xavi77, post #17189748]

Can a partial fix make the problem come back when I press the feed?

Yes. One case worked at idle but failed again after enabling feed: the display went off and the motor ran continuously. This indicates another bad device in the drive/brake path remained, requiring further parts replacement before stability returned. [Elektroda, xavi77, post #17111459]

What’s a safe 3-step process to replace the faulty parts?

  1. Isolate power, discharge caps, and document wiring/photos.
  2. Desolder and replace the motor drive transistor, brake transistor, and 15 V zener; inspect pads.
  3. Verify 5 V/12 V regulators, then cold-start and test feed with torch disconnected. [Elektroda, stasiekb100, post #16821788]

Does replacing the motor drive transistors alone ever resolve it?

Yes. One user replaced the motor drive transistors and confirmed the welder worked again. Always verify supporting components first, but this shows the drive devices can be the primary failure. Document part numbers before ordering replacements. [Elektroda, xavi77, post #17189748]

What are the typical user-reported symptoms before repair?

Continuous wire feeding even with the torch disconnected, a nonfunctional display, and noticeable heating with odor from internal parts. These signs point to a shorted drive path and stressed power rails. Use these cues to focus diagnostics on the motor control section. [Elektroda, daniel9541, post #16818451]

Is this issue limited to the 200MMA, or seen on other Magnum MIG models?

A 280 model exhibited the same failure set and was fixed by replacing the motor drive transistor, the brake transistor, and the 15 V zener. This suggests a shared control design across models, so methods may transfer. [Elektroda, stasiekb100, post #16821788]

What’s one expert tip to avoid repeat failures after repair?

“Replace the zener with the drive transistor; the transistor went linear and burned out when the zener failed.” Pairing these parts reduces callbacks and protects the new MOSFET during test. Check for solder bridges around the gate network. [Elektroda, stasiekb100, post #16821788]

When should I stop DIY and use a service center?

If you lack isolation tools, can’t verify 5 V/12 V rails, or the motor still runs after replacing listed parts, seek professional service. Remote diagnosis has limits; measured data on your exact board is essential for safety and accuracy. [Elektroda, bearq, post #16818890]
Generated by the language model.
ADVERTISEMENT