cybertig 130 'issues'

[Jake3126]

Would anyone have some guesses as to what would make a cybertig 130 draw more than it's rated supply current as soon as the main contacts inside are engaged? After it threw the breaker I took the side off and found the main contacts stuck closed from the arcing. I haven't been able to locate any components that are obviously toasted.

I've started checking the transformers but haven't found anything so far (I think I have one more to check judging by the wiring diagram)

I'm beginning to think it's a smaller, less robust component causing this and I wondered if there were any common problems with these older machines that someone here might know about.

Thanks in advance any enlightenment.

[Hobart Expert Rock]

HI JAKE3126........... THAT IS A FAIRLY OLD VERSION...... IF MEMORY SERVES ME CORRECTLY THERE IS A POWER SUPPLY DRAWER IN THAT UNIT.........IT HAS 2 COOLING FANS ON THE SIDE....ALSO ENCLOSED INSIDE IS A HALL EFFECT PC BOARD.... THIS SUPPLY'S A +/- 15 VOLTS BACK TO THE CONTROL BOARD..... BELIEVE IT OR NOT I MIGHT HAVE THE CORRECT PC BOARD SCHEMATIC IF YOU CAN SUPPLY A SERIAL NUMBER......... I HAVE A 1 IN 3 CHANCE OF BEING CORRECT......... DIFFERENT VINTAGES OVER THE YEARS........... IF I DON'T HAVE THE CORRECT ONE I THINK WE CAN STILL GET ONE FROM ELLEN......................AND WELCOME ABOARD..........................
..................YOUR CALL..........................ROCK.............
[email protected]

[Hobart Expert Dave]

This welder also had a Fly Back diode on the control circut. Inside on the aluminum heat sink you will find 2 scr control rectifiers and 1 Diode. More than likly this diode is shorted causing the excessive draw.
Dave Evans

[Jake3126]

I think I may have provided some incorrect information.

It is a 130 series, Model CT-300, Serial 12RT-35246. I believe it might have been a 120 series, since the guy I bought it from gave me a 120 series control panel and some spare parts with it.

It has a single cooling fan and the only components that appear to be tray mounted are the electronics on the main control board/tray.

I didn't see a black diode on the AL heat sink (the sink attached to the front side of the central web inside the case under the lifting eye) There are a couple of white cylindrical links I took for fuseable links, but they may be something like what you're talking about.

I appreciate the quick response, if you both were refering to another model I hope you have the same kind of knowledge with this one.

Thanks

[Jake3126]

Ok, I figured out that the cyldrical unit about an inch long mounted to the center of the heat sink is the diode (It's labeled with the proper symbol). I assume the units mounted above and below it are the rectifiers. I'll pop it off and check the resistance each way, hopefully that's it (as long as that part or an equivilent is still available).

Thanks again

[Jake3126]

Unfortunately not the diode

I checked the diode. According to my cheap multimeter it's OK with a step voltage of about 340 (I believe this is mV on this meter). (also is open in the correct direction)

Thanks for the tip.

[Jake3126]

I found the problem, it was actually really obvious if I had looked at the capacitors a little more. Rock, if you can get that schematic I'd still be interested...the DC volt, DC amp, and AC amp meters don't seem to be working properly.

I think this might have been a case of sabotage. I bought this welder from an auction house that was selling off items from a snow-mobile dealership. I have a feeling this might have been a bankruptcy auction where the previous owner didn't want the bank to get too much from anything.

Anyway, the two capacitors that are wired in parallel and are supposed to connect two primary windings were bypassed. The wires going to the two primaries were wired to the same terminal on one capacitor. I suppose you would see this same high amperage draw issue if a capacitor shorted, though they say they are internally fused. I'm not quite sure how one 10 or 1 ga wire can make that big of a difference by connecting two primaries, but it did.

Thanks to both of you for your help, I'll keep your advice in mind if I have any other issues in the future.

[Hobart Expert Rock]

HI JAKE3126......... I'LL LOOK AT THE SERIAL NUMBER LATER ON THIS MORNING AND TELL YOU HOW OLD THE UNIT IS....... AS I RECALL THOSE WERE POWER FACTOR CAPACITORS ON THE BACK WALL OF THAT UNIT AND JUST HELD THE VOLTAGE CONSTANT..... THE SLIDE IN CONTROL UNITS KNOWN AS DRAWERS WERE IN SERIES SUCH AS PROGRAMMER 100, 120, 200, ALL THE WAY UP TO 800 SERIES PROGRAMMERS.......... THERE WILL BE A 6 DIGIT NUMBER INSIDE THAT IS THE SPECIFACATION NUMBER OF THE PROGRAMMER.............................. I MIGHT??????????? HAVE A DRAWING I CAN TRY AND FAX WE'LL SEE.................ROCK..... [email protected]