Let's say you have two options: First, you could send in your PC boards for assembly as individuals. Second, you could send them in a panel. That's all fine and dandy. For a few, send individuals. For a bunch, panels might make more sense. But, when you do go to quote and order, how do you count the parts?
Let's take this example. As a single, this board has 32 line items on it's bill of materials. That's 32 unique parts. Counting all of the individual part placements, there are 56 total parts: 42 smt and 14 thru-hole. So, naturally, if you quoted the assembly of 20 of this board at Screaming Circuits, you would enter your desired board quantity as 20, 32 total unique parts, 42 smt and 14 thru-hole.
But what do you do if you send it in panel form? How do you count? It's actually not as difficult as it seems. In this example, it's in a panel of four. There are still only 32 BOM line items, but there are four times as many placements. That means that if you quoted this, as a panel, you would enter 32 total unique parts, 168 smt and 56 thru-hole parts. If you still need 20 of the final boards assembled, you would enter 5 as your desired board quantity.
In the end, you will have 20 assembled boards. In case you are wondering about the cost, there won't be a difference. As long as the final number of boards (after the panel is broken apart) are the same, your cost will be exactly the same for panel vs. one up. You don't save any money by sending in singles. However, if your board is panelized and all of your parts on on reels, full or partial, you can save money by ordering Short-Run production.
50 Years ago today
Robert Rushworth flew the X-15 to Mach 5.03 at 100,400 feet altitude