A drop pan system for collecting discharge samples from combineharvesters or other conveyed machines or implements features a support housingattachable to the machine, a drop pan receivable in a nested position withinsaidhousing, and a magnetic hold/release mechanism with electro-permanent magnetsresponsive to selective energization to switch from a holding state emittingan externalmagnetic field for holding the drop pan in the nested position, to a releasestatecancelling said external magnetic field to thereby release the drop pan fromthehousing. A power supply is positioned on the housing at an area that resideswithin afootprint of the drop pan's nested position. Differently sized drop pans areincluded,and the housing features alignment guides for self-aligning the selected panduringmagnetically aided placement thereof. Electrical components of the housing arecontained in an enclosure that doubles as a support for the electro-permanentmagnets.
