Clear inputs. Visible assumptions.
How we use evidence and what our calculations can tell you.
Source selection
The knowledge vault supplies topic relationships, not automatic publishable facts. A selected record is checked for identity, quality state and field-level evidence. Its path and content hash are stored in an internal audit snapshot. Numerical catalogue claims are excluded from the site’s editorial import.
Guides link to manufacturer instructions, university extension publications or original engineering references where they support a statement. A manual for one product is not treated as a specification for all products. Imported, inferred, missing and conflicting information is never silently upgraded to verified.
Original planning content
Our job briefs, scenario worksheets and checklists organize decisions a user must resolve. They do not copy full vault entries or publish permutations of model and task names. The sources below each guide distinguish the underlying reference material from our planning structure.
Field capacity
In metric units, theoretical capacity in ha/h is working width in metres multiplied by speed in km/h, divided by 10. Effective capacity applies the user’s efficiency fraction. US customary capacity uses feet and mph with the 8.25 conversion factor. Hours equal area divided by effective capacity.
Efficiency is entered as a percentage and converted to a decimal for the formula. Overlap should be counted once. The cost result multiplies working hours by a user-entered hourly rate; the site does not supply prices or convert currencies.
Iowa State Extension: machinery selection and field capacity.
PTO torque
The torque calculation follows the power identity P = Tω. With power in kW and speed in rpm, torque in Nm is P × 1000 ÷ (2π × rpm ÷ 60). It describes a steady operating point. It does not account for shock loads, starts or component ratings.
Hydraulic power
Theoretical hydraulic power in kW is flow in L/min multiplied by pressure differential in bar, divided by 600. Applying the supplied total efficiency estimates output at that assumed point. The tool does not model a complete circuit.
Parker Hannifin: motor formulas.
Unit definitions and display precision
- 1 foot = 0.3048 m; 1 mile = 1.609344 km.
- 1 acre = 0.40468564224 ha.
- 1 US liquid gallon = 3.785411784 L.
- Mechanical horsepower = 0.7456998715822702 kW; metric horsepower is not used.
- 1 psi = approximately 0.06894757293168361 bar; 1 lb-ft = approximately 1.3558179483314004 Nm.
Internal calculations retain precision; normal displays use up to two decimal places. Unit switching converts the stored quantity rather than repeatedly rounding the display value. Very small results use scientific notation so they are not presented as zero.
Review and updates
A displayed update date identifies an editorial change, not a field test or expert sign-off. Changes to content or formulas require rebuilding the static site. Where exact requirements remain unresolved, use the correct machine manuals and obtain a documented answer from the equipment supplier.
Illustrations
The homepage tractor scene is AI-generated and labelled as illustrative. It is not a photograph of a tested machine combination and is not used as technical evidence.