.png?height=120&name=CalcuQuote%20Logo_Blue@2x%20(1).png)
These two figures represent an estimate of the materials that are lost during setup and running of the job.
In order to more accurately reflect the cost of components during the RFQ process, CalcuQuote uses Lead Quantity and Attrition Rate on the Bill of Material tab.Lead Quantity
"Lead Quantity" as it appears on the BOM and Material Costing tab is a figure that represents the approximate number of components (or other materials) that are lost during the setup of the job. For example,you may lose 25 pieces as part of loading a reel of 0201 resistors into a pick and place machine.
Attrition Rate
"Attrition Rate" as it appears on the BOM and Material Costing tab is a percentage that represents the approximate ratio of components (or other materials) that are lost during the run. For example, if there are 1000 placements of an 0201 resistor by a pick and place machine, the machine may lose 5% of the components (50 pieces) during that activity.
Example
For an 0402 resistor, the lead quantity is set at 20, and attrition rate is set at 5%. This resistor has 2 placements on each assembly for a total of 500 assemblies. Here is how the system would determine the Required Quantity for the material costing screen:
= (20 pieces of leader) + [(500 assemblies) x (2 pieces per assembly) x (1 + 0.05 attrition)]
= 20 + [500 x 2 x 1.05]
= 20 + [1000 x 1.05]
= 20 + [1050]
= 1070 Required Total Quantity