On Tuesday 02 August 2016 13:45:52 Rick Lair wrote: > I am wondering if it just temperature related, I will have to turn the > AC unit back on, and put a temp sensor in the cabinet, and see if I > can get a common trip temperature maybe. Dropping the cabinet temp 20 > degrees has got to make some stuff contract a little bit, maybe enough > to make a crappy connection on the circuit board if it is a cracked > resistor or capacitor?? > > > > Rick > And a high ESR (think an unwanted resistor in series with the capacitor) will often improve with a lack of adequate cooling, until such time as the cap actually over-pressures and vents, or in some cases just blows its top.
That was in fact the clue that made me think tired old caps in the first place, Rick. That might well be Leonardo's problem too. High humidity might be electrical leakage caused by the leakage products on the pcb from a failed cap, so while I am not as positive in Leonardo's case, its a possibility that should cause it to be visually inspected for such leakage. Its generally white, looking a bit like dried pancake batter. > On 08/02/2016 11:56 AM, Leonardo Marsaglia wrote: > > On the Mazak lathe I often have problems with the drives tripping > > out when there's high humidity levels (85% and up). In fact, the > > drive doesn't want to turn on at all, whenever I turn on the machine > > it's on fault state. Most of the time it happens on one of the > > drives, but if the humidity is too high, both of them are tripped. > > This one only has fans but no air conditioning system. > > > > I don't believe that a low humidity enviroment could cause the > > problem, but I'm just guessing. > > > > The same machine had a Fanuc 3 phase AC drive for the spindle. That > > one tripped out from time to time, but worked ok. One day, it > > started to trip several times on the day, until finally we never > > could make it work again. Apparently the problem was on the main > > board, because everything else on the power stage was just fine. We > > replaced the drive because a Yaskawa drive was cheaper than the main > > board only. > > > > 2016-08-02 12:39 GMT-03:00 Rick Lair <[email protected]>: > >> Hello Guys, > >> > >> I have a Fanuc triple axis servo drive on one of my machines, and > >> since last Thursday it has been randomly tripping out, and faulting > >> the cnc control. It is from roughly 1995, and has been running just > >> fine up until this point. Even while just sitting powered up, but > >> with no servo motion commands it will trip out and shut off the > >> machine. I noticed though, that when the cabinet doors are shut, it > >> trips almost all the time, when I open the cabinet doors, it has > >> been running since Friday, only tripping just once, early yesterday > >> morning. The cabinet is air conditioned, and had the thermostat set > >> at 95 degrees for the point to turn on. We turned it down, to 75 > >> thinking that would help, but I think it actually made it worse. > >> Would there be any way that on an old PCB, if something was going > >> south on it, a humidity level that was too low could cause > >> something to not work, and when it is hot and humid, it would > >> function properly? > >> > >> Here is a link to an identical PCB, > >> > >> http://www.fanucworld.com/media/image/800/0/A20B-1001-0770%20Front. > >>jpg > >> > >> -- > >> Thanks > >> > >> > >> Rick Lair > >> Superior Roll & Turning LLC > >> 399 East Center Street > >> Petersburg MI, 49270 > >> PH: 734-279-1831 > >> FAX: 734-279-1166 > >> www.superiorroll.com > >> > >> > >> > >> > >> ------------------------------------------------------------------- > >>----------- _______________________________________________ > >> Emc-users mailing list > >> [email protected] > >> https://lists.sourceforge.net/lists/listinfo/emc-users Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
