A new sensing shelf for the high-speed VPrep Pipetting Station (Velocity11, Menlo Park, CA) expands system versatility. Versatile shelf configurations enable the workstation to perform complex pipetting sequences, while at the same time achieving high throughput. This new shelf configuration can be used to sense if a microplate is present prior to processing eliminating the possibility of costly pipette head crashes. Other shelf configurations include an Alignment Shelf that ensures precise positioning of labware on the VPrep. It is used primarily for 1536-well, and low volume (small diameter) 384-well microplates. Its design actively holds the plate while it is under the pipette head, releasing the plate once the processing is completed. The VPrep Vacuum Alignment Shelf utilizes vacuum to hold a wide range of plates down flat to ensure reliable pipetting in every well. The VPrep Weigh Shelf provides precise liquid level control for auto-filling reagent reservoirs. The VPrep Pipetting Station features a choice of interchangeable 96-, 384-, 8- or 16-channel pipetting heads.