Broken Welder

[50cal]

Hello,I am having a problem with my welder it is a Hobart TR 250 HF.I bought it new about 25 years ago and it has served well.I have never used it much on the HF side,because most every thing I do is stick.Now the problem,just tried to use it today and it would barely strike an arc turned it up same thing only a little better but still not good enough to weld anything.Got out my meter and checked power coming in 240 volts good.Took apart the leads and checked continuity all was good,put everything together still the same.Is there any one here that could give me an idea where to go next?Thanks 50cal

[50cal]

I,took the top panel off for a look see,no rats nest mouse nest or obvious problem.blew a small amount of dust out still the same problem.any ideas?Checked the Hobart lineup for new machine the offerings have really shrank.50cal

[bhoward]

Does the fan come on? Does it have any weld output in AC? Try changing the range switch a few times to remove any corrosion. Do NOT use your meter (if digital) with the HF on. (It will fry)
From here on we need to go inside. Are you comfortable with that? Do you have a code #?

[50cal]

The fan comes on and the relay operates everything sounds as it has for years just not enough current to weld.I havent tried it in AC or HF just DC.Thanks for the tip on the meter.50cal

[bhoward]

Probably the fine adjust pot or the control diode bridge. From the diagram, it's a pretty simple welder. I'll know better when you do the other tests.
Brian

[50cal]

Ok,I had already tried working the range and polarity controls to remove corrosion.but I tried it agian to be sure same results not enough power to weld.I tried it on AC same as DC.Switched on the HF and it sounds as it always did with the extra buzz.Tried the tig torch there seems to be more arc there.50cal

[bhoward]

Probably the fine adjust pot or the control diode bridge. From the diagram, it's a pretty simple welder. I'll know better when you do the other tests.
Brian

Sounds like this.
Brian

[bhoward]

See if this helps.

[50cal]

Allright,I am not very electronic minded.I do have the origional owners manual can you tell me where to find these parts,as in near to which major component?Could not find anything with that exact names.50cal

[bhoward]

My book calls it "fine current control" and "control rectifier" There is also a 15A "control circuit fuse" to check.
The " fine current control" is the amperage adjustment in the center of the front panel (# 33 in your book)
The "control rectifier " is a block about 1" square and 3/8" thick mounted to the back of the front panel (#31 in your book)
Remember, power off and unhooked before any covers are removed. Capacitors can hold voltage for a long time after power is removed. Don't go any farther if you are not comfortable and competent in this area

[vicegrip]

ventureline or enelpac

or ???? will see this eventually.

H.F. rely's on capacitors that may leak by now.
Or try cleaning the gaps if they are dirty or have accumulated a film of
some kind.

VG

[50cal]

Looks like you guys were up a lot later than I was.I checked the fuses early on into this they were ok.The picture you sent was pretty blury.I dont know if I could tweek the resolution to clean it up.My book shows the fine control but not at that # it looks like it is #20 potentiometer.The control rectifier doesnt show up at all.I will get some # off of the data plate when I go out to the shop today and post them.Thanks for the safety tips and help I will be very careful.50cal

[bhoward]

The 100K limit on files has me stumped. I cannot figure how to shrink a print and have it clear. If you PM me with your email, I'll send you a PDF of a very good testing manual.

[acwd1950]

50cal,
Where are you located?

Steve

[50cal]

Hello,finaly got time to get back to this spent some time working on my grading tractor today replacing the water pump,I sure do miss that welder.Right now if I want to weld I have to use the 110 miller mig,no contest.The spec # is 6088-1 model is TR 250 HF nearest city with weld supliers is Omaha NE.Thanks for everyones help 50cal