hobart 200 tripping main panel circuit breaker

[phoffman]

I have had my Hobart 200 mig welder since new. Recently I experienced the circuit breaker on my main panel tripping after welding 10-15 small welds. I reset the breaker and can continue on for approx. another 2-20 welds. I have the heat setting at 4 or 5 and the wire feed at 3-4. I am welding the floor in a 1979 MGB with fairly thin metal - 18 to 20 gauge steel. The breaker is a 55amp and less than 1 year old. I also changed the tip with same results.
Any ideas?
Thanks for any help, I just found this forum.

[Hobart Expert Rock]

PFOFFMAN..............WELCOME ABOARD............. I'M GOING TO GUESS THAT THIS IS A BETA MIG MACHINE..........ONE OF 7 OR 8 VERSIONS..........CAN YOU SUPPLY SERIAL NUMBER OR SPECIFICATION (SPEC) NUMBER FOR EASIER DIAGNOISIS..... ALSO IF YOU CAN TELL US WHAT YOUR OPEN CIRCUIT VOLTAGE OCV IS THAT WOULD BE USEFUL INFORMATION............. HANG IN THERE WE CAN HELP.............................ROCK............. ..........
[email protected]

[phoffman]

I am at work now. I will get the serial #, etc and respond tomorrow.
Thanks for the quick reply.

[Franz]

Another question, what manufacture and type of breaker.
Murry, Crouse Hinds, and other fully magnetic breakers of the homeowner quality line can become oversensitive and trip when they shouldn't.

[lranch]

You say that the main breaker is tripping, or is it the branch (welder outlet) circuit? Two things you should check. 1. open main breaker and check torque on branch breaker. Thermal dynamics will cause lead connections to become lose. This condtion will result in a steeper slope in I that will continue to "come on" over time. That is, breaker will start to trip sooner and sooner. 2. "Clean tight" machine connections. A "gettin green" work lead ground connection or power cord will result in a thermal runaway or over current condtion (like hearing loss, slow and unnoticeable until it becomes obvious). Also as Franz has advised, some breakers become sensitive after time or operational cycles. Any breaker that you suspect has drifted out of spec. should be replaced at once. Anyway, be careful and good luck.

[phoffman]

Here is some more information that you have requested.
The welder serial # is 83WS02083, the spec # is N6331-2. Also the open circuit voltage is 40V according to my manual.
The main panel circuit breaker is the one tripping. It is a 50 amp capacity, I will have to see what type it is. I installed it less than one year ago. I previously had only a 30amp circuit breaker running this system, that is what the sales rep from the welding store I bought it from said I needed. I had been having this same problem with the 30 amp breaker tripping and I read thru the manual and noticed it had a 50 amp circuit breaker recommended. I also replaced the wiring from the circuit breaker to my 50 amp socket with the recommended wire size.
The work lead grounding cable and clamp are the original but seem to be in good condition.
Hope this helps.
Thanks guys.

[Tom]

If you replaced a 30 amp with a 50 amp breaker it is quite possible that the wire was originaly sized for 30 amps. If this is the case the wire is overheating and causing the breaker to trip on thermal overload. Distance from the main pannel will be a determining factor in the wire size required for a 50 amp service.

Tom

[Hobart Expert Rock]

PHOFFMAN..............HERE IS WHAT THE MANUAL SAYS... 200 VOLTS INPUT EQUALS 44 FULL LOAD AMPS, APPROXIMATE LINE FUSE RATING IS 60 AMPS....COPPER WIREING IN CONDUIT NUMBER 8 FREE AIR NUMBER 10 COPPER GROUND CONDUCTOR MINIMUM SIZE IS NUMBER 10.........LINE VOLTS 230 EQUALS 38 LOAD AMPS FULL, APPROXIMATE LINE FUSE RATING IS 60, COPPER LINE WIRE SIZE IN CONDUIT NUMBER 10, FREE AIR NUMBER 10, COPPER GROUNDING CONDUCTOR MIN. SIZE IS NUMBER 10.;....................... NOW IF EVERYTHING IS CORRECT GIVE ME A CALL AND WE WILL DO SOME INVESTIGATION......ROCK........................... ..... [email protected]

[phoffman]

I replaced all of the wiring with #6 wire (the thickness of a #2 pencil). This is the wiring from the circuit breaker to the wall plug. I also have an extension wire that I made out of same #6 gauge that I plug the welder into. The welder has two ways of strapping the machine, a medium amp and a higher amp setting. It has always been on the lower setting. This is done by physically bolting a wire onto one terminal. ( I do not have the manual in front of me to explain better at the moment. Also I am welding .035 wire using stargon gas. I understand the need for the correct wire and breaker size, but why is this happening after I have increased the wire size and breaker size. (I was originally running 10 gauge wire and a 30amp breaker fro many years.)
I can replace the breaker with a 60amp one if necessary, I was going by what the electrical staff at Home Depot recommended.

[lranch]

Well, it sounds as if rig current draw is increasing for some reason or you have additional equipment that is exceeding total panel capacity. At this point I would suggest you get hold of a clamp meter with a peak hold feature. This will allow you to cut to the chase by recording total and individual loads. You might as well ask to borrow a kidney rather than a Fluke, but somebody might let you borrow a Greenlee. Good luck.

[Franz]

I'll let ya borrow either one of my Flules, but ya gotta find the sumbiches who stold them.
The 44 amps would only be drawn if the machine is cranked full out, what kind of amperage are you running to the wire?
I'm still betting on a defective breaker, probably a fully magnetic homeowner grade Murry.

[TheOldOne]

What kind of wire did you run? #6 aluminum or #6 copper?

[Hobart Expert Rock]

PHOFFMAN........... LET'S TALK ABOUT OCV A MINUTE I KNOW THE BOOK SAYS 40 DC VOLTS FOR OPEN CIRCUIT......... I ACTUALLY NEED YOU TO MEASURE YOURS PLEASE.......... ALSO HAVE YOU LOOKED INSIDE YOUR MACHINE YET........... DO YOU SEE ANY INDICATION OF OVERHEATING, LOOSE WIRE'S, CAPACITOR (S) DISCHARGED OR VENTED............. MEASURED YOUR DIODES, IS YOUR FAN TURNING AND COOLING THE UNIT DOWN........... IS IT REAL DIRTY INSIDE AND NEEDS CLEANED OUT........ USEING A CLAMP ON AMP METER LOOKS LIKE A GOOD IDEA TO ME..... THIS WILL ALLOW US TO SEE EXACTLY WHAT IT IS DRAWING........ CIRCUIT BREAKERS, ESPECIALLY HOUSEHOLD TYPE TEND TO DETERIORATE AFTER A FEW TRIPS........... INDUSTRIAL HIGH RESOLUTION CIRCUIT BREAKERS TEND TO LAST LONGER HOWEVER THE COST IS ABOUT 3 OR 4 TIMES THE COST OF A HOUSEHOLD TYPE....................THE NUMBER HERE IS 1-800-332-3281 AND YOU WILL GET STEVE OR MYSELF.................... YOUR CALL......................ROCK.................... [email protected]

[Hobart Expert Dave]

One thing you need to remember is there is a High inrush current when these old welders are triggered on. You could get as high as 70 amps real quick and then it drops to a normal operating amerage. This is normal for these older welders. When we first put them out we required a 50 amp fuse. (not a breaker) Breakers are a quick reacting trip and a fuse is alittle slower to melt the elemnt inside. So Breaker size should be 70 amps. (unless as Rock said you get a High resolusion breaker) This is a slow blow type breaker that will alow for this inrush current.
Thanks
Dave Evans

[phoffman]

My main panel is a Crouse Hinds and the breaker was a Murray brand. There are Bryant and General brand breakers in the panel, I will ask my local electrical supply what they recommend. I spoke to Steve this morning and I will try a new 60amp breaker of hopefully better quality this weekend if I get the time. I have a 9 month old baby boy and he keeps me and my wife very busy.