TIG welder help

Date 05-23-2009 03:53

I have a singe phase Hobart TR-250 HF that is not giving any current.
I have spark with the HF on but not with it off, but the spark I have is like having static.....no power.
The welder was at a company and set at 440. I changed the links according to the book to 230. I have a arc and mig welder that work in the shop so I don't think it has anything to do with the wiring in the shop.
Is there more to changing the welder over from 440 other than changing the links?
The welder was in a shop for 10 years without being used, but was working great up till then.
I cleaned and wire brushed the connections on the torch and ground. Also reset and cleand the plugs.
Any idea's?

Thanks,

By DaveBoyer (*****)

Date 05-23-2009 04:17

Can You hear the contactor click when You try to initiate the weld if using the foot pedal? There should be a standard/remote contactor switch, do You have it in the proper position? Check for fuses or circut breakers that operate the control circut, they might be inside the housing. Is there no output on the AC and DC settings? Check the rheostat that controlls the amperage, it might be coroded or burned out.

It sounds to Me like You have HF output only, but no weld output. If You set the contactor to the ON or STANDARD position can You stick weld with it? Try it on AC & DC.

By wiskybuck (*)

Date 05-23-2009 16:22

Yes I can hear the click when I intiate weld with the foot pedal.
I have the switch in the correct position.
Fuses are good.
I get the same result with it on AC or DC straight or DC reverse polarity. along with hi, med and low range.
I will check the anp control next.(how do I check to see if it's burned out?)
I have had the contactor in the On and srandard positions
Don't have stick setup.

By Lawrence (*****)

Date 05-23-2009 17:10

Does your welding power supply have a voltage meeter?

If it does.. When you set it on SMAW mode or depress the foot pedal in GTAW mode the open circuit voltage should jump to between 40 and 90 volts.

You don't need a SMAW torch... Just set the machine for SMAW... Remote contactor control in the off positon... When this is done you should have current and it will be indicated (if you have a meeter) as soon as you flip the switch.

Just remember that if your GTAW torch is hooked to the machine the electrode will be hot when the OCV is active.

If it has OCV during SMAW mode than the problem probably lies in your foot pedal or solonoid in the machine... Both relatively small problems.

By wiskybuck (*)

Date 05-24-2009 01:02

There is not a voltage meter on the machine.
I will try a different pedel.

Thanks guys

By DaveBoyer (*****)

Date 05-24-2009 03:13

I havn't seen inside oue of those Hobarts, but the old Millers I am familliar with have a wire wound rheostat for the amperage controll and a similar linear unit in the foot pedal. There is resistance wire wound around a ceramic insulator, You can see if there is a burned off section on it. A carbon brush rides in these wires, it needs to make good contact too.

The contactor You hear clicking needs to make proper contact too. If dirt, insect nests, etc. got between the contacts while in storage, that could cause the problem You are having.