Contactor chatters when cold

[rlitman]

found this thread while searching , too bad it has all the water marks on the pictures

Unless it's your exact contactor, I'm not sure how much the watermarks will matter, because there are lots of styles out there. But that flash rust was exactly what we were saying could cause chattering, and simply taking it off with some scotchbrite so the pieces of the core can come together and make good electrical contact can make a big difference. I don't think I would bother to take it much past that though, and reapplying lacquer and paper gaskets is almost certainly way more effort than a universal replacement is worth.

Unfortunately, if it's spent much time chattering (and arcing while doing so), there's a decent chance the contacts are eroded, and those too are generally not worth replacing in small contactors (like replacing carb jets nowadays).

 

[RPH]

found this thread while searching , too bad it has all the water marks on the pictures

Pretty good idea of what needs to be done. Get the part number and we should be able to AB technical pdf.

 

[micromind]

added to my TDL list . inspect contactor on lathe .
not much experience wit them. are they obvious how they come apart? all I know is it's Allen Bradley

If it's an Allen Bradley 500 or 509, it's pretty easy to take apart and put back together again.

Since it's on a machine tool, lots of oil everywhere, it's possible that cold oil is keeping it from closing completely and after the oil warms up a bit and gets thinner, the noise disappears.