need replacement part

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i am very new at welding and purchaced this unit from an older guy for a good deal............i have an older P&H welder(big unit 4'x3'x4') and a seperate portable wire feed that connects to the P&H....the wire feed unit is  two seperate parts 1) speed control for wire feed  and 2)drive motor for wire feed.....the speed control is a miller overhead unit that would hang above the work area...the box was damaged and a new box was made ...the system is working fine except for today smoke rose from the speed control box that houses the relays and other electrical parts that drive a seperate hobart wire feeder... like i said it works fine but there is a part that looks like a capacitor that is labeled "super pup MPY2W3 3.0 MFD 200 V.D.C."  this part is connected to the relay that drives the wire feed....i removed the burnt "super pup" and the system still works, but when the bernard trigger is released after weld , the wire feed continues for a split second....and depending on the variable speed....wire is  expelled an inch and a half....not a big deal but the wire seems to stick to the weld bead and is quite annoying......this setup is older but durable and i have no idea what this "super pup" part does nor do i know where to get a replacement......i can post pics if you likethanks for taking the time to help
Reply:pictures are always good. they may not help too much, but they might. get some pictures of the fine details (labeling) and put something next to it for size comparison. hook us up with a few picks of your set-up also. i am having a dificult time understanding how you have your machine setup. however, that may be due to my excessive sleep depervation (spelling?) lately.later,Andy
Reply:From looking at this site:http://www.sbszoo.com/ve6sbs/sale/caps2.htmIt appears it is simply a capacitor, albeit (big word score) a high voltage one. I'm guessing you could probably replace it with this 3.3uF 200v cap from digi-key:http://search.digikey.com/scripts/Dk...me=493-1400-NDBUT, you have to be sure to get the polarity correct so you don't blow it up...does the old cap have a + or - designation on it?- John
Reply:I'm also guessing that this cap is part of an arc-suppression circuit to absorb the load when the relay opens. Here is an excerpt from an article at:http://pickercomponents.com/Applicat...ntact_Life.pdfIf this is the case, if it is just a cap and resistor hanging off your relay, the 3.3 uF cap would work just as well as the original 3uF one.-------------------------------------------------------------------------Contact ProtectionPerhaps the most popular method of quenching an arc between separating contacts is with an R-C networkplaced directly across the contacts. As the contacts just begin to separate and an arc ignites, load currentfeeding the arc will be shunted into the capacitor through the series resistance, depriving the arc of some ofits energy. As a result, arc duration will be shortened and material loss will be minimized.Contact Protection Diagram(4)Theoretically, the ideal arc suppression method would simply be a capacitor placed directly across thecontacts. However, with no resistor in the circuit, when the contacts make, there is nothing to limit capacitordischarge current. This nearly instantaneous discharge current can generate a brief, but severe arc thatmay cause welded contacts, depending on contact material and characteristics. Thus, the resistor isnecessary to limit capacitor discharge current. However, there is one drawback. That is, the resistor tendsto isolate the capacitor from the very contacts the capacitor is supposed to protect. Because of this, theamount of resistance should be kept as small as possible.
Reply:i got a comparable part ordered ...maybe next week...ill replace and test and report my findings. i really appreciate all the help...and ill post some pics of this system...yooull get a laugh.....this sytem was for a dockyard production line .... it could weld a ferry....lol