Or perhaps harvesting system, but "Schemata des Ernteaufbaus" indicates that it refers to the actual physical equipment, which may be more clear using setup.

layout or configuration are other options

Does not Google well, but there is this:

As such, this method facilitates the effective clarification of crude, high-density cell culture harvests in a single-use large-scale setup.
http://www.contractpharma.com/issues/2015-06-01/view_feature...

For heart valves in this case:
Applying this criteria in our harvesting setup limits
the availability of valves dramatically, and with this study we would like to see whether perfectly suitable
valves can in selective cases be harvested up to 48 hrs after death and beyond.

http://www.mrc.ac.za/cvdmd/section2.pdf

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Note added at 1 hr (2015-06-17 16:54:49 GMT)
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The Schemata in this case includes the designations of the equipment and tubing, so it seemed to me that it would most likely be a drawing. I suppose you could still use system in this case.