[RFI] LED streetlights - Lumenistics

[nm8rmedic]

The problem with ROHS is it seems to be one factor that fosters growth of tin whiskers and dendrites.   Lead in solder prevented that.  NASA produced a good resource paper on the subject titled Basic Information on Tin Whiskers.  Dendrites and tin whiskers are not the same creatures.   ScottSent via the Samsung Galaxy S8+, an AT&T 5G Evolution capable smartphone
-------- Original message --------From: Gary K9GS <k9gs at gjschwartz.com> Date: 3/4/20  20:03  (GMT-05:00) To: rfi at contesting.com Subject: Re: [RFI] LED streetlights - Lumenistics I work in electronics manufacturing. Lead free solder for surface mount devices has been commonplace for more than 20 years.It's stable and proven technology. Higher solder temperatures are correct but nothing more than a different process variable. 73,Gary K9GS-------- Original message --------From: Ken Winterling <wa2lbi at gmail.com> Date: 3/4/20  6:17 PM  (GMT-06:00) To: KD7JYK DM09 <kd7jyk at earthlink.net> Cc: Rfi List <rfi at contesting.com> Subject: Re: [RFI] LED streetlights - Lumenistics I believe you can thank lead-free solder for many failed joints. It needshigher heat to melt than the leaded type.  I’ve been working on equipmentfor over fifty years and see more PCB solder joint failures in the recentdecades than when I was much younger.KenWA2LBIOn Wed, Mar 4, 2020 at 18:20 KD7JYK DM09 <kd7jyk at earthlink.net> wrote:> "I remember years ago when municipalities replaced incandescent traffic> lights with LED lights to save money. They discovered that in winter the> snow would cover and block the lights since they didn’t generate heat> like their predecessors.">> Another issue, both with LED traffic signals, and automotive lights,> which personally bugs the crap out of me, is the hot/cold of just the> weather alone causes the solder joints to fail quickly, and I see lamps> with various blocks, chunks, stripes, et cetera where a section no> longer illuminates.>> One would have imagined this to be resolved in initial testing, but I> still see it on a daily basis, after, what, some thirty years of> technology evolution?>> Kurt> --KenWA2LBISent from one of my mobile devices_______________________________________________RFI mailing listRFI at contesting.comhttp://lists.contesting.com/mailman/listinfo/rfi_______________________________________________RFI mailing listRFI at contesting.comhttp://lists.contesting.com/mailman/listinfo/rfi