Electronics Forum | Thu Apr 07 12:02:08 EDT 2011 | grahamcooper22
Clearly you are above liquidus for too long so you can either increase conveyor speed or lower some zone settings. With your current recipe you don't mention the conveyor speed or the total profile length. Also ...are your max / min slopes really so
Electronics Forum | Thu Apr 07 11:39:48 EDT 2011 | remullis
My oven profile is 155,160,165,180,220,245,255,227 Cooling Zone 132/92. This is a 8 zone CV820 Technical Devices oven. My assy profile using Datapaq Q18 - Base on one probe feedback - Positive slope (7.09), Pos Slope Time (.45), Rise Time (1.17), Me
Electronics Forum | Fri Dec 16 11:04:23 EST 2005 | chunks
Over all time will be dictated by your conveyor speed. Your conveyor speed will be dictated by your products time above liquidous. Time above liquidous is dictated by the manufacturers specification. Time and temp before reflow will have to be ach
Electronics Forum | Fri Nov 30 06:16:25 EST 2007 | aj
Hi all, What do most of you aim for when profiling BGAs ? Currently I aim for time above 60 or 70 secs but I read a report that 40 secs would be more suitable. Also peak temp - I aim for 240-245 but again this report stated 230-235. any input app
Electronics Forum | Mon May 28 09:37:02 EDT 2007 | davef
Look here: http://www.aimsolder.com/techarticles/Time%20Above%20Liquidus.pdf We have no relationship, nor receive benefit from the company referenced above.
Electronics Forum | Wed May 09 17:13:06 EDT 2007 | zanolli
Re: 63/37 paste reflow Is there a standard reccomended time (ball park) above liquidus? What are the negative ramifications if the TAL is too short or too long? Thanks in advance
Electronics Forum | Thu May 10 08:05:22 EDT 2007 | pjc
30 to 90 seconds TAL is typical.
Electronics Forum | Thu May 10 08:09:52 EDT 2007 | davef
There is no standard for time above liquidus. It is described rather broadly by the solder paste supplier. Reflow Zone: If the temperature is too high, boards may char or burn. If the temperature is too low, cold and grainy solder joints will resul
Electronics Forum | Fri May 18 12:09:20 EDT 2007 | ed_faranda
I have been TAL around 45 to 90 seconds. I prefer the longer TAL so, I set my profiles around 80 seconds. In the old days (Before RoSH), the longer times would help with wetting. But, since Lead-Free, well. We all know the story about wetting now
Electronics Forum | Fri May 25 13:38:15 EDT 2007 | mfgengr
TAL Too Long - dull solder joints, dewetting. TAL Too Short - cold solder, insufficient wetting. You want TAL to be as short as possible (but not lower than 30 seconds), but long enough for every solder joint to be above TAL for at least 30 seconds.
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