Two years ago, we visited Schweitzer Engineering Laboratories (SEL) to better understand its new captive greenfield PCB facility. We recently returned, this time to discuss how this bold vision has transformed the industry. Barry Matties met with John Hendrickson, engineering director, and Jessi Hall, vice president of vertical integration, to discuss the transformative capabilities of Factory Core, SEL’s custom manufacturing execution system (MES), which allows for real-time monitoring of workflow and machine performance, and has led to impressive improvements in quality and cost efficiency.
This interview profiles several of SEL’s amazing supplier partners and outlines a living, breathing example of the most critical PCB processes, equipment, and business methodologies for printed circuit board manufacturers today.
Barry Matties: John and Jessi, it is great to talk with you both. I’d like to start by talking about how you manage your workflow through the factory.
John Hendrickson: We run everything through Factory Core, our internally developed MES. You can see a whole-factory view on our big monitors; click any work area and you’ll see current work in progress (WIP), completed units, machine status, and more in real time.
Matties: Why was building your own platform smarter than buying an off-the-shelf package?
Hendrickson: It’s part of our strategic plan. About six or seven years ago, we started Factory Core in one of our other plants, knowing we could leverage the existing foundation and tailor it for this workflow instead of starting from scratch. We wanted to own the MES layer and tie it tightly to the business systems.
Matties: What information matters most when viewing the dashboard?
Hendrickson: There are two things: Is our WIP healthy, and is product flowing? I watch the WIP count per area for bottlenecks. I check for when a station isn’t producing. For example, with Rout/V-score, they hit goal yesterday, but their WIP dried up because upstream didn’t deliver enough panels. The problem was flow, not productivity.
We do the same for the lab queue. For example, we can see the cross-sections they cut yesterday for copper-thickness checks vs. final and backup tests. It’s all about keeping the line balanced.
We now have an organic-contaminant tester. We use it to analyze the DI water. Because we recycle that water, monitoring organic build-up is critical. At first, we outsourced the testing, but it proved too important, so we brought it in-house for real-time data.
To continue reading this interview, which originally appeared in the August 2025 edition of PCB007 Magazine, click here.