new owner of a l-tec 250 hf

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ok so i just picked this old l-tec 250 tig been practicing away but ive noticed that even when im not on the pedal at all there still is a lil current goin through the torch so if i touch it to the work piece theres a lil spark and you can hear the machine slight hum until you break connection i thought that if i dont have my foot on the pedal that the torch is spose to be dead am i mistaken ?
Reply:on most TIG welders you are right. Look for a large contactor, it might be stuck closed. should have voltage to the coil when foot control is pushed. turn the HF off when using a voltmeter around a TIG welder. Does the HF turn on and off with the foot control? If it is a heliarc 250 HF. No large contactor. Welder is SCR controlled. Check the spark gap and make sure it is not arcing. then check out put with a meter see what is there with out pushing foot control. You can go to www.ESABNA.com Look for manual F-14-316. If you can't find it. send me your e-mail by PM Post a picture of the welder front.
Reply:yea its a heliarc 250 hf  took the covers off today crazy amount of dust in there so cleanin up and figure i should set the spark gap
Reply:ok so i set the spark gap to .o25 like it says it was at about 30  cleaned the whole machine out put the covers back on and tryed it torch still stays live not enough to hold a arc just enough the cause a lil spark when you touch the work piece and then the machine hums like when shes workin and if ya dont shut it down to pull the tungsten out it will give ya a lil tickle lol so when you say check out put with a meter with out pushing the foot control you just want me to put a mulitimeter on thework leads comin out or somewhere else and do you want amps or volts sorry for all the questionsLast edited by deutzman; 10-31-2013 at 11:31 AM.Reason: spelling
Reply:also i noticed that when i start welding i hit the pedal initiate an arc start to get a puddle and its like the metal wicks up onto the tungsten  at first i thought i was diping the tungsten in the puddle but after grinding a tip and restarting like bunch of times i could actually watch the metal wick up onto it and the tungsten it never dipped into the puddle it always stayed above it and with 2%thoriated after it did that the arc would still stay pretty steady and i could keep going but with 2%lanthanated  it would start an arc way easyer but it would wick that metal up and ball up the end right away and the arc would wander so bad you couldnt weld with it also im in DCSP am i doing something wrong is something not set right or does it have something to do with the torch staying live thanks for any help
Reply:Are you running it DCEP (electrode positive) instead of DCEN as it should be?MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:The tiny spark sounds like the HF is in start or continuous. Even though the torch is "dead", the HF is there ready to initiate the arc. What you describe is common, especially with machines that have a lift start function..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:i have it in hf start mode for the mild steel im trying to practice on i just thought that the hf start was only initiated when i hit the pedal but if its normal than cool beans i wont worry about it lol but on my machine it has AC     DC straight polarity and DC reverse polarity im assuming the DCSP is the same as DC electrode negative right this is my machineLast edited by deutzman; 10-31-2013 at 09:49 PM.
Reply:Originally Posted by deutzmanon my machine it has AC     DC straight polarity and DC reverse polarity im assuming the DCSP is the same as DC electrode positive right
Reply:it says on the tag esab welding and cutting products type FC-4 serial 1-96
Reply:i just put my muiltimeter on the work and electrode coming out of the machine and in DCSP i have 40 volts if that helps at all
Reply:What do you get when you unplug the foot peddle?  If OCV goes away, the switch in the peddle is either misadjusted or failed close.MM200 w/Spoolmatic 1Syncrowave 180SDBobcat 225G Plus - LP/NGMUTT Suitcase WirefeederWC-1S/Spoolmatic 1HF-251D-1PakMaster 100XL '68 Red Face Code #6633 projectStar Jet 21-110Save Second Base!
Reply:i unpluged both plugs for the foot pedal  and left it on tig remote  setting and still had juice to the torch so would that mean that somewhere inside theres a contactor stuck inside the machine?