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# Siemens line computer

Tal

Siemens line computer | 10 March, 2002

how siemens line computer automatic calculate the tolerance for the x,y body and for the Packaging X,Y Tol ( i need a rule or formula)

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Siemens line computer | 12 March, 2002

Shoot a note to Stefan at http://www.steering-inc.com

Check out his manual Siplace for dummies

Siemens line computer | 13 March, 2002

It is a little bit sad that I know this - be prepared for some confusision - this is not as simple as it might seem.

Something tells me that the calculation of the tolerances for the nominal dimensions is a little inconsistent. As I recall the default value is 0.200mm regardless of the value entered in the nominal dimension field. This tolerance is not recalculated when you make changes to the nominal value. I haven't checked this lately. A tip, if you don't already know, is to delete the value in the tolerance field then press enter - the original default value will be restored but I believe that sometimes this will result in the value 0.300mm. This works for most tolerance fields.

The Packaging Tolerances are calculated automatically from the nominal dimensions not the body size. There are 5 values that are calculated by the system 0.5mm, 0.7mm, 0.95mm, 1.3mm and 1.8mm. Both packaging tolerances will change to the value that is appropriate for the smaller of the two nominal dimensions. If the nominal is less than 2.0mm the tolerance is 0.5mm If the nominal is greater than or equal 2.0mm less than 5.0mm the tolerance is 0.7mm If the nominal is greater than or equal 5.0mm less than 9.0mm the tolerance is 0.95mm If the nominal is greater than or equal 9.0mm less than 35.0mm the tolerance is 1.3mm If the nominal is greater than or equal to 35.0mm the tolerance is 1.8mm A maximum value of 3.0mm can be entered manually in the packaging tolerance field but that too is probably limited to some extent by the nominal dimensions. I just did a quick verification of this but I can't be sure that it works for all types PDC, FDC, BGA etc. or all versions of software, time of day or whether or not it's a leap year. Frankly I wouldn't put all my trust in this automatic calculation - it's a bit illogical. Thank goodness you didn't ask for an explanation of the the angular tolerance. Please remember that I did not invent this stuff I am merely reporting what I think I know.

Siemens line computer | 13 March, 2002

thank you, Dave, I replied to Tal's e-mail.

I am not aware of any formula used to determine the tolerances. We were collecting data from Topline, Siemens and other component supplier. On small components, the aim was to detect components on the side.

Siemens line computer | 13 March, 2002

Did we catch you napping?

Siemens line computer | 13 March, 2002

Could this be Brian Stockley??? A true Siemens God??

Cal