HELP.... No trigger response from my MIG Welder after Making a HUGE mistake.

[Mitch_c]

I have a Century 125GS MIG welder. Some time ago, I modified it by installing a Contactor so that the gun trigger would control power to the feeding wire (welder trigger originally only controlled power for wire feed and wire was hot when machine was turned on).

Today I made a horrible mistake. I have a 120/240 plasma cutter and without thinking, I plugged the Century welder into it's cable, which was operating on 240V.. Arc struck once, then POOF.... no wire feed or power.

The cooling fan still runs and I can get wire to feed manually by pushing the Contactor's button, but it does not activate power transfer to the feeding wire.

I see no burnt wires or components...

- How do I diagnose what component got fried?
-

[Louie1961]

I would check the diodes first. There aren't any real electronics in that thing. So if its not the diodes, you likely fried the transformer.

[BaTu]

But Wait,,,, you have a 120v receptacle with 240v in it? How does That happen?

[Mitch_c]

But Wait,,,, you have a 120v receptacle with 240v in it? How does That happen?

I have a 240V plug for my stick welder and an adapter cable to allow my 120/240v plasma cutter to use the 240V. Cutter male plug is std. 120V config and machine autosenses what the voltage is.

[albrightree]

Do you have continuity across the "thermal protector" on the white wire. ie. the white wire on the fan to the white wire on the transformer ? The fan is before the thermal protector, so the fan should still run even with protector tripped. It could also have taken out your new contactor , how is that wired ? to the trigger also ? It lists all the OCV's so it should be easy to follow the voltage to its termination, and that likely will be the faulty component.

Good Luck

[California]

Taker a single strand of 12ga insulated wire and lash that adapter semi-permanently to the plasma cutter's cable.

[GeoNOregon]

Is the wiring diagram on the inside of the lower side cover, (below the access to the wire spool and wire feed roller assembly?

I spent a bunch of time looking for a wiing diagram for my red Century, then turned red, myself, when I pulled the lower side cover and found the damn wiring diagram! LOL

Theoretically, you should have pooped/popped the circuit protector wired into the big-azz coil sitting under the rectifier. That's what it's for, over heat, overload protection. Not really understanding if you ran 240V through it, or what, since I don't understand exactly what you did, I can't say for certain.

Did anything smoke?

Look at the wiring diagram, (if it's not there, let me know, I may have one, or be able tog et you to one.) Louie1961 may have posted the correct one for you, but you didn't give the model number.

If you have the correct wiring diagram, pull all the sheet metal off the welder, and look at the wiring and the diagram until you see and understand their connection. Not the connections, the connection between the diagram and the actual wires. Cut all the zip ties off.

Once you understand what correlates between the real world and diagram world. Start labeling everything. I've been doing this since Christ was only a corporal, and I STILL use white masking tape for the white connections, and black tape for the black connections. Sometimes, a wire will be black, but make a 'white' connection. Or vice versa. Or a yellow connects to a white or black. THAT is where mistake get made. Use brown masking tape to make labels when wires connect to components.

Once you understand real world vs diagram world, have everything labeled, then,and only then disconnect anything. Make sure you can take every connector off, and put it all back together. Take before and after pics, (I'm waaaay older than the cell phone era, and never think of pics. My mid still defaults to processing film!)

Once you can take it apart and put it back together, then take everything apart. ALL connections. DO I need to tell you to unplug the effing thing, too? I doubt it... after what you did, you're likely scared to plug in your toaster, now... that will go away in a couple days.

When everything is apart, you need a piece of paper, and a volt ohm meter, and you need to check every piece of wire, every connection on every component for a continuity beep, first, then for ohmage.

You WILL find the dead stuff before you run out of things to test.

When you test the red, orange, yellow, green and white wires disappearing into the transformer, you should be checking each of the colors against the white wire, based on louie's diagram. Each should have a different ohmage.

The two vertical lines between the half round lines where the colored wires are on the left, and the Heat 1-4, reactor coil, wire feed control, etc are, means there is no direct connection between the sides divided by the two lines. It is a magnetic connection. (Notice the Reactor Coil only has one set of double lines? That's because the reactor coil is only half of a transformer. It needs to have continuity between it's two wire ends, and NOT be ground out to the big chunk of rusty metal it's in.)

If you didn't let any magic smoke out, then nothing should be ground out in the coils.

Most likely, if you sent 240VAC through things, you cooked the little wires in the wire feed, CO2 solenoid, and possibly in the control switch(es), if they have little coils of wire.

If you get to through my nickel lecture on how to troubleshoot and haven't found dead stuff, let me know. IF you have, and know what dead, or want to bench test it to make certain it's dead, (always a good idea before buying replacement parts), let me know. Louie may be right on popping the diodes, they won't smoke, but the transformer would smoke like mad.

The contacts could be cooked in the gun, or anywhere else you see switch symbols, (those are two dots with angled line NOT connecting the dots.) They will cook just like points in a car... oh yeah, cars don't have points, any more... LOL BUt, you'll see, from the diagram, below, the gun does have point contacts. Too much current/voltage WILL cook them. Connect your continuity beeper to each of the connections to the MIG gun. When you push the button, it should beep. Test the voltage ('heat') selection switch the same way, between the black terminal and each colored terminal connection.

My advice is don't check this, then check that, based on what anyone tells you. Follow a set method and protocol for disassembly, re-assembly, then testing. When you get the thing apart, and don't get a replacement part for several weeks/months, you don't want to be lost when you put it back together. You want it to be like getting together with an old friend.



GeoD

[Welder Dave]

What plasma cutter do you have that uses a 120 volt plug for 240 volts? Something doesn't seem right and actually seems like it could create a dangerous situation. Lots of inverter machines automatically adjust to the voltage but sure don't do it with a 120 volt plug. Be glad all you did was damage or burn out your Mig welder.

[Broccoli1]

What plasma cutter do you have that uses a 120 volt plug for 240 volts? Something doesn't seem right and actually seems like it could create a dangerous situation. Lots of inverter machines automatically adjust to the voltage but sure don't do it with a 120 volt plug. Be glad all you did was damage or burn out your Mig welder.

A few of the import machines actually come with this backward arse adapter plug

[Broccoli1]

You can see one in this photo

YES Welder Plasma cutter 124/240v machine

[Josey]

My cheap hitbox tig came with a dual voltage adapter like that. Its a 200 amp supposed to be
60% at 200 amps. I have never even tried it yet

[California]

Chevy Bolt is dual-voltage like that welder. Owners make or buy that adapter (and one for a dryer outlet) to charge twice as fast at 240.

[danielplace]

My cheap hitbox tig came with a dual voltage adapter like that. Its a 200 amp supposed to be
60% at 200 amps. I have never even tried it yet

That adapter should have never been made. The company that thought that up was just plain stupid. That is a VERY irresponsible way to engineer a multi voltage design. Safe to say that there is no UL listing or other approval from any testing agency.

[Denis G]

That adapter should have never been made. The company that thought that up was just plain stupid. That is a VERY irresponsible way to engineer a multi voltage design. Safe to say that there is no UL listing or other approval from any testing agency.

Agree. Usually a 120VAC plug uses a neutral. There's no neutral on the three prong 240VAC plug, so the only way that adapter can work is if it uses the ground on the 240VAC plug as a neutral.
Using the ground wire to carry current is what makes that adapter dangerous.

[danielplace]

Agree. Usually a 120VAC plug uses a neutral. There's no neutral on the three prong 240VAC plug, so the only way that adapter can work is if it uses the ground on the 240VAC plug as a neutral.
Using the ground wire to carry current is what makes that adapter dangerous.

Not what you think. 240 in 240 out. Ground stays ground. It isn't 120 out and them using one leg and ground for it.

Still two hots. One is on what is normally the neutral side of 120 volt female making that end a 240.
It is to run machine on 240 volt outlet. It is a 240 volt welder too so no need to ever pull 120 from a 240.

Everybody thinks that is what is going on there. You missed it. That isn't 120 volt in the female plug. It is 240 in and 240 out. They used a 120 volt configuration to feed the machine 240 volt so you use te same 120 cord/plug and use this and run on 240.

So if someone plugged anything 120 into it KABOOOM !!! Imagine stretching out a 120 cord to extend your reach to the welder on 120 which someone could easily do. Then you have your 120 cord for your grinder and you grab wrong extension cord. KABOOOM goes the grinder.

Lots of ways that could go wrong. You just never send 240 out a common 120 volt configuration and any manufacturer should KNOW this and never design something the way they did. It is horrible engineering to say the least.

In order to use same cord this was the answer they came up with. Engineer should have had someone smarter checking the design for obvious flaws.

Most proper multi voltage units like Miller, Lincoln and even Harbor Freight all have a cord system that prevents you from feeding your machine the wrong voltage nor are there adapters that are unsafe in design used to switch the machine from 120 to 240.

[Denis G]

Not what you think. 240 in 240 out. Ground stays ground. It isn't 120 out and them using one leg and ground for it.

Still two hots. One is on what is normally the neutral side of 120 volt female making that end a 240.
It is to run machine on 240 volt outlet. It is a 240 volt welder too so no need to ever pull 120 from a 240.

Everybody thinks that is what is going on there. You missed it. That isn't 120 volt in the female plug. It is 240 in and 240 out. They used a 120 volt configuration to feed the machine 240 volt so you use te same 120 cord/plug and use this and run on 240.

So if someone plugged anything 120 into it KABOOOM !!! Imagine stretching out a 120 cord to extend your reach to the welder on 120 which someone could easily do. Then you have your 120 cord for your grinder and you grab wrong extension cord. KABOOOM goes the grinder.

Lots of ways that could go wrong. You just never send 240 out a common 120 volt configuration and any manufacturer should KNOW this and never design something the way they did. It is horrible engineering to say the least.

In order to use same cord this was the answer they came up with. Engineer should have had someone smarter checking the design for obvious flaws.

Most proper multi voltage units like Miller, Lincoln and even Harbor Freight all have a cord system that prevents you from feeding your machine the wrong voltage nor are there adapters that are unsafe in design used to switch the machine from 120 to 240.

Inconcievable!
(to quote Vizzini)

[danielplace]

I read what I wrote maybe wasn't written correctly.

I meant if you were using the 240 adapter and strung out a 120 volt type of normal extension cord to extend your 240 volt to the machine which you could do and then grabbed the wrong end thinking it was your grinder extension cord. Fry the grinder or whatever you might mistakenly plug in or someone else might.

The Harbor Freight multi volt most use two cords so maybe if you didn't set the voltage correct on switch not sure if there is something preventing you from smoking the machine but at least there are not crazy mixed voltage adapters used which is the real issue with that other design.

[Denis G]

I read what I wrote maybe wasn't written correctly.

I meant if you were using the 240 adapter and strung out a 120 volt type of normal extension cord to extend your 240 volt to the machine which you could do and then grabbed the wrong end thinking it was your grinder extension cord. Fry the grinder or whatever you might mistakenly plug in or someone else might.

The Harbor Freight multi volt most use two cords so maybe if you didn't set the voltage correct on switch not sure if there is something preventing you from smoking the machine but at least there are not crazy mixed voltage adapters used which is the real issue with that other design.

I was just joking (movie quote). I have no direct experience with that adapter, but if it is as you describe, then I completely agree with you about the danger of it.

[CAVEMANN]

Danilplace said:

"That isn't 120 volt in the female plug. It is 240 in and 240 out. They used a 120 volt configuration to feed the machine 240 volt so you use te same 120 cord/plug and use this and run on 240."

That's just freakin' stupid IMO, is it even legal under electrical code??

[California]

Danilplace said:

"That isn't 120 volt in the female plug. It is 240 in and 240 out. They used a 120 volt configuration to feed the machine 240 volt so you use the same 120 cord/plug and use this and run on 240."

That's just freakin' stupid IMO, is it even legal under electrical code??

Not legal. You can't buy that adapter in the US according to discussion in the Chevy Bolt user group online. (Some appear on Ebay).

But people build that, or one similar, for themselves, to charge their car from a welder or dryer outlet twice as fast.

The US Bolts are made to accept 120 or 240. Because the European Bolts have the identical charging circuit, and 240 is the standard there.

I expect we'll eventually see US Customs, per an order of OSHA or somebody, halt import of the cheap welders if they include that adapter.

[CAVEMANN]

Not legal. You can't buy that adapter in the US according to discussion in the Chevy Bolt user group online. (Some appear on Ebay).

But people build that, or one similar, for themselves, to charge their car from a welder or dryer outlet twice as fast.

The US Bolts are made to accept 120 or 240. Because the European Bolts have the identical charging circuit, and 240 is the standard there.

I expect we'll eventually see US Customs, per an order of OSHA or somebody, halt import of the cheap welders if they include that adapter.

It should be stopped, IMO anything that allows that to happen is UNSAFE!

[Done right fabricati]

No. No one is stopping any form of unsafe import sales into America just because it’s dangerous as all hell…. In fact I still see tons of these welders for sale and just today went to harbor freight and seen both male and female versions of this adapter being sold (they even put it on the first set of shelves so EVERY dumb *** can find/buy/use this thing).also I’m sure just as u can charge ur multi volt machines twice as fast with it, Im sure some retard thinks he can cook his meth or crack twice as fast using this adapter with his 120 stove/microwave…… god bless America and the ever winning Democratic Party (short bus drivers anonymous)!!

[StandarDyne]

That adapter should have never been made. The company that thought that up was just plain stupid. That is a VERY irresponsible way to engineer a multi voltage design. Safe to say that there is no UL listing or other approval from any testing agency.

No doubt it was made by the same "electrical engineer" who said, "If you blow a fuse, just stick a penny into the fuse holder! No more blown fuses!"

[Welder Dave]

It shouldn't have been able to be sold in N. America without meeting ULC or CSA standards. That said I knew a guy that worked for a trucking company and a big customer sold mostly really cheap Chinese products in their stores. Apparently it was worth it to have to pay fines and take stuff off the shelves when customers had issues and/or it was discovered they didn't meet the required codes like CSA. Things like $10 trouble lights with tiny wires that would burn out in short order.