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SMT electronics assembly manufacturing forum.


Quad 4C pickup limit error

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#76219

Quad 4C pickup limit error | 25 August, 2016

We have been having a recurring error on one of our Quad 4Cs. When it picks up the first of 8 47uF SMT capacitor it stops with a limit error. If we do 2 consecutive function 30s, the problem goes away until the next board. The first function 30 results in height 1 and center 12438, second function 30 (normal value) function 30 is height 204 and center 12440. MOD code 15, soft home for z is 25. The extent for the cap 211 by 207 both at 25% tolerence, z height 170, alighn 4, delay 16. Any ideas on how to fix this problem? Thanks

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#76221

Quad 4C pickup limit error | 25 August, 2016

If I have to guess then I would say the machine is first picking up a larger nozzle to pick up this part.....the nozzle is not seating on the z-rod correctly and causing a problem. Check to make sure the nozzle is being mounted correctly. You may also want to put some superlube on the z rod bellows.

If you need more help....contact me at my email at: www.precision-repairs.com

Bob

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#76308

Quad 4C pickup limit error | 8 September, 2016

Hello Bob, we changed the nozzle z parameter until we got limit errors and backed up 1 mil. There was a slight reduction in the limit errors on the pickup of the component but it is still a problem. With the mod code we adjust the soft z height to about 201 . Is it possible at that position the laser and the z rod are mis-alighed? Should we try to change it to lets says 240?

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#76311

Quad 4C pickup limit error | 8 September, 2016

If its a tall part and you are trying to scan it lower than 200 or so...you can have this problem (limit error). Thinking of things to look at.....Is your z-rod spring sticking? Push up on it and it should spring back with NO hesitation...if it does....buy a new z-rod. I don't understand why you are playing with the z soft home and changing the mod code. That's usually set on the machine and not changed.

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#76312

Quad 4C pickup limit error | 8 September, 2016

Thanks Bob, I will change the z-rod just to make sure. It is a tall part read at 180. The nozzle height bugs me because we have 3 machines and the first one has a nozzle height of 238 while the 2 others around 200. I am thinking this parameter may adjusts the nozzle height with respect to the laser window.

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