I have a 170 mig Chicago electric welder and I need to replace the bridge rectifier but I am having trouble finding a replacement. Any ideas of where I can find one?
Nathan, I have a Firepower FP120 and the rectifier shown in this video appears to be the same as the one in my unit. I am getting no DC output at all and am wondering if I need to replace the rectifier.
Thank you for the video. one of the better how-to's /walk-thru's I've seen everything was very well explained, you didn't skip any important parts, and you didn't rush through anything
Also I have a Clarke 130en mig, the diode bridge actually smokes when I turn it on, the whole set up is very similar to your firepower. My only question is where did you get your new rectifier, and how much did it set you back?
Anthony Filipski Thanks for the comments! You can get welder parts at NAPA (I know, I was surprised too!) If memory serves, I believe this rectifier bridge was around 60 bucks? The old one also smoked when I turned it on.
Great! Thanks! I have been going back and forth on a forum with a tech and he said I needed to check the AC to the rectifier and now I know what he is talking about. Very good!
Matt, I've got a situation w/ a Century 170GS (220 unit). Can you assist? Not getting any power to the torch end. Using w/ a Generac 5500 and when I trigger the torch the generator lug down as though I'm welding but nothing at the torch tip. Seems to be grounding internally. Anything?
Hi On my millermatic 251 . I just notice when my ground clamp is grounded to a piece and then turn on the machine it sets off a high 4 code, when I remove ground clamp it clicks and then goes to a normal display and then I can clamp the ground again and proceed as normal to wield , It only does this when the ground clamp is clamped on start up, this unit never did this before. What might be the problem ( a short may be ) Thanks for the informative vid.
Great video, I have a mig pal 100 all the sudden stoped working, I made it work by by passing the overload and it worked good for the rest of the day. Next day I turned the switch to start working, no power at all. It won't turn on. (It's not the on-off switch). Any idea? Thx.
The overload is your duty cycle if you bypass overload you could not only burn up Transformer but burn up capacitors transistors anything affiliated with that circuit and burn your house or your garage down where you're working because after the machine starts to see too many amps that is what the overload is there for I think of it like this think of a breaker in your fuse box that breaker if it's 2:20 or 1:20 either or has a load rate limit of amps and wire that must not exceed the amperage of the fuse or breaker cuz that defeats the whole purpose now more likely your limit switch was bad and there's a way that you can test a certain limit switch is not all of them so if you ran that welder and bypassed its duty cycle whether it's a plasma cutter or a welder or some type of machine that creates AC or DC output them Transformers and all them components that are included with it can heat up and most of your rectifiers in welder certain welder and plasma cutters will have a thermal disc which is housed in the rectifier they call it like a hockey puck summer big summer small depending on whatever they designed that machine and that rectifier to use and a lot of times they have to be depressed within a certain torque value to get the correct ohms readings out of them and depending how the circuitry goes they could be leading up to a control panel or board with multiple different components and if you bypass that switch you could burn all that stuff up and it's hard to tell what went bad on a PC board even if there's no signs of burnt because they are varnished with a special substance so you cannot test them now you can scrape back the varnish and proceed with your testing depending on what the diagram wiring allows you to test within that circuit if you got 10 things in one circuit they're all incoherent of each other if one thing is bad it's hard to test that exact part because you're going to get false readings because they're nine other circuits in that 10 circuits completion so another way that you could do it as you could do an oscilloscope and find your power and ground to the board without actually being hooked up to the machine and put power directly into the PC board while it's live under current then test the wave pattern on your DC out to see if it's giving out a direct current from the board at which part it is supposed to give out DC now testing all the other components within that circuit you would have to scrape off each a little bit to test if they are in the right ohms or amperage a would have to be done with power going to the machine or bored and possibly under a load so there can be quite inclusive and conclusive testing has to be done and troubleshooting is to find the exact problem
Thanks for your interesting demo on the rectifier replacement. I may have such a problem on an older Henning Hansen 160, and I was wondering if just the diodes could be replaced since the metal plates are just for a heat sink aren't they? Any advice... I think the H. Hansen may have alot of good life left in it. I might have exceeded its duty cycle rating which was about 35%. Thanks again. Rational on Alaska
my wire feed stopped working and I took the gun apart and everything looks good there. the welder seems fine if I have excess wire out of the tip and pull the trigger, it has power and zaps the metal but wire feed wheels inside unit just don't turn. any ideas about what I can try?
Kevinvansea Does the motor make any noises when you press the trigger? If it does, something is making the wire very hard to push through the gun. If it doesn't then the motor may be bad.
+MattsMotorz hi I have a duel mug welder that the power button turns on but it doesn't feed wire or anything there's a little fan in the back that turns on but nothing else
Excellent video Matt. Thank you for posting. I have a FirePower Fp-120 which I have put to great use except a week ago it suddenly stopped working. It odd because the last time I used it my spool ran out so I decided to stop for the day . The next time I went to use it I installed a new spool and when I pulled the trigger on the torch - nothing! No relay clicking inside the unit as it should and the wire feed motor doesn't spin. The cooling fan runs and the main power switch indicator light is lit showing there is power to the unit. I've gone over the entire control board and can find nothing wrong. I am getting no DC output off the rectifier so perhaps this is the problem.
Hi You seem to know alot about welders, I have a wsme 200 ac/dc with Pulse Tig Welder everything works, except the pulse, I cant get the pulse to become active. any idea what pc board controls the pulse or if you have any suggestions on what I can try.
Seems like you can do nothing. It must be pcb or microchip controller malfunction. Only control board replacement will help. Or maybe its just potentiometer failure if you have it for pulse control.
![Fixing a MIG Welder [Rectifier Replacement]](/img/logo.svg){kind=logo}
