Electronics Forum | Tue Jun 14 11:25:19 EDT 2005 | pr
Sounds a little tough to achieve. Math isn't my strongsuit but...If you run a million parts through the machine, you will have 200 feeder exhaust's (assuming 5000 per reel). So if you have your machine error out after 3 attempts/misspicks you will ha
Electronics Forum | Wed Jun 15 00:50:32 EDT 2005 | Frank
From my understanding: Sigma is the same as one standard deviation. So 3 sigma is the same as 3 standard deviations. It all boils down to how repeatable your machine is. Another way to look at it is the probability (or confidence) that the machin
Electronics Forum | Mon Jun 13 16:15:04 EDT 2005 | peter ng
Dear all, We faced some major issue in setting our company target to 500 points per million at machine throw rate.It might be caused by human error,machine,feeder,environment or other factor.We need some opition and advise on how to achieve this targ
Electronics Forum | Mon Jun 13 16:17:30 EDT 2005 | peter ng
Dear all, We faced some major issue in setting our company target to 500 points per million at machine throw rate.It might be caused by human error,machine,feeder,environment or other factor.We need some opition and advise on how to achieve this targ
Electronics Forum | Tue Jun 14 16:21:15 EDT 2005 | pr
My chipshooter will not "Time out", it will try to pick 3x and then alert the operator. Which would be 3 misses per empty reel. Unless I misread his post, he said 500 ppm at the placement machine. That makes a big difference.
Electronics Forum | Tue Jun 14 15:03:15 EDT 2005 | slthomas
In that the machine times out and waits for a feeder refill and doesn't just skip that part and leave the space empty, it's not a defect. I have found 500ppm *fairly* easily attained in SMT depending on the board mix and how you define (1) a defect,
Electronics Forum | Tue Jan 24 21:30:09 EST 2012 | jorge_quijano
It means the machine places another component, no missing PCBs are built. As an update I have measured this % in the newest machine and it is below 1%, but in our worst machine (old quad) it is as high as 9% for a small batch of 10 boards (~15 comp p
Electronics Forum | Wed Feb 15 10:37:19 EST 2012 | caerleon
The only way you will be able to measure it is to count the reel before you put it on the machine, count them when they come off and deduct the amount expected to be placed. you will then have the result of attrition on the machine. or.. Pick the p
Electronics Forum | Tue Jan 17 21:58:42 EST 2012 | jorge_quijano
Hello guys I hope you can help me, I had worked with machines that usually tell you how many components are dropped off, now I have some very old machines without such information, any idea how to measure if attrition rates are normal? I expect to be
Electronics Forum | Sat Feb 04 23:09:00 EST 2012 | jorge_quijano
Thanks for the info, I will check tolerances and the quadaling option. As an update I ran this past week and machine was arround 5% for a very small lot size, for a larger size lot it was less than 2%, Now I know it still higher than our newest machi
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