Hobart 135 wierd problem

[bkrantz]

I have a 135 mig that is about one year old. In the middle of some auto fender repair (aren't vacations great?) it is acting strange. When I clamp the ground cable to the car chassis, the wire feed motor runs slow, intermittent, or not at all. With the ground clamp free, the wire feed runs fine. I have tried grounding to other big masses of metal, and the result is the same. 3 days ago, the welder worked fine. Any ideas of what could be wrong or what to check? Thanks, Bob.

[cope]

Check with Mitrowski in South Houston. They are a warranty center I believe.

Larry
Mitrowski
1315 College
South Houston, TX 77587
713-943-8032

[Paychk]

With the ground connected to what ever you want to weld, but without striking an arc, does the wire feed consistently? If so maybe the feed knob was bumped and is now set wrong and needs re-adjusting. Another possiblity is the welder plugged into an extension cord? is it damaged and not putting out full power to the welder? If the speed isn't consistently or not at all, then some thing is wrong and you'll need to have it checked.

[bkrantz]

Re: Hobart 135 wierd problem

Thanks for the replies. Latest update: when plugged directly to wall outlet, it seems to work fine. Extension cord is 25 ft 14 gauge, and has always worked before. I do have some concerns about electrical service in our new subdivision: not sure if we are getting rated voltage. How sensitive to input voltage are these welders?
Bob

[Paychk]

you may want to take a meter to the outlet and check for 115v, while you're at it maybe check the extension cord. One last thing would be to pull the outlet from the wall (circut shutoff) and check the wiring method at the outlet. Sometimes the wires are just back stabbed into the outlet, it is better if the screw terminals are used and properly tightened.

[horseman1]

Hi,

I would use a 12 ga extension cord for a 115 V welder, not 14 ga. Actually, I would stop using that one altogether since you have proven it works OK without the cord. It could be a fire hazard at some point if it really is bad. Many of my tools are adversly effected by cheap extension cords (table saw, drill press, compressor etc. ) Just my experience. Good luck!

Kurt

[echo8287]

Ext cord

Since you now know its the cord,Cut the ends off the extension cord and re-attach. If you have an ohm meter or could borrow one you could ohm each lead on the cord out and check for resistance on each wire. You might do this before you cut the ends off and re-attach and then again after. If you have a question on your electrical power, an ohm meter(on volts) might give you a little information on that. At least you would know your voltage on both legs.(you would need a 240 volt outlet for that or take panel cover off if you are comfortable doing that). You could check the dryer outlet,or an A/C disconnect or anything 240volt that is accessable. Is this an outlet you regularly use? or a seldom used one? Is the outlet wired correctly? You might have to check for loose connections in your panel. I agree with Paychk above. David

[cutter]

I sure think you need to do as David, Kurt & Paychk all suggest, Bob. I have run across plenty of odd behaviour involving weak connections in circuits. One fairly common 240v problem is aluminum wiring in breaker boxes & service entrances which often results in the wires "shrinking" away from the screw lugs. This causes poor contact resulting in high current drain (heat) as well as unequal voltages on one leg vs. the other. I have seen several situations where ovens either would heat erratically or would trip breakers & the solution was simply to tighten the connections all the way from the meter base to the first copper wire. And of course, this can affect your 120v circuits too if there is a weak connection to the buss bar of either incoming leg & such a fault can occur on the power company's side of the supply, too. I find a bad connection somewhere between the transformer and the service entrance once or twice a year and electrical troubleshooting is only about 10 -15 % of my little repair business.

Those stabbed-in connections on wall outlets often cause similar faults on 120v lines & in My not-so Humble Opinion, should be outlawed as a public nuisance. They are certainly a frequent nuisance to me. I have often wondered just whose bright idea it was to allow them to pass code in the first place & just who lobbied (bribed) whom to get that ruling passed? They nearly all fail sooner or later if they are used very much, especially in the very common situations where several outlets are run in parallel around a room, each one adding to the total load on the little copper strips that barely pinch the wires. Jeez, I hate those things. They'd have to be improved a whole lot just to suck.

Okay, end of rant. My point is that since you have isolated the extension cord as the rotten apple, check with a volt meter to see where the weak connection or bad wire is & eliminate that problem. BUT bear in mind that you could have more than one weak point in the supply so check the voltage at the outlet and even in the breaker box if you're up to it. And be certain that you are using a dedicated circuit. Just having a couple of light bulbs running on the same circuit can cause problems. What gauge wire runs the circuit to your outlet? It should be at least 12 gauge.

And finally as Kurt said, I personally would not use a 14 ga. extension cord for my HH135 because I think it's just too skinny for a 20 amp circuit even in its best & newest condition. Any questionable component in your circuit can cause high current drain & that causes heat and HEAT is the killer of all electrical devices.
A 115 volt welder is marginal in its very concept and welders are merchants in heat by nature so we're starting off with one foot on a banana peel anyway. Using a borderline cord is adding stress to the little machine when we need to be making life as easy for it as we possibly can.

[horseman1]

I've used this trick: measure the line voltage while the circuit is under load. This is a much better indicator of a problem than just measureing the voltage. You want to see if you get a voltage drop accross your wireing. As an example, 22 gauge wire can provide enough current at 115 volts to run your meter. It will not run your drill press though.

A cheaters way to check this without a meter is to hook up a light bulb to the same plug as the load device. You get some idea of the current capacity of the circuit when the bulb dims and stays that way. This assumes that the load device is running at it's rated current and is not broken. This has worked for me in proving there was a problem with one of those blasted pug ins on the back of a duplex in the barn.