Lift Capacity
This is the maximum load the three point hitch can lift at a given point. It is not the property of a single part but a result determined jointly by hydraulic working pressure, cylinder bore, lift arm geometry and relief valve setting. In tractor hydraulics the working pressure is typically in the 180–220 bar range.
Capacity is not determined by pressure alone. The force produced by the cylinder is pressure multiplied by piston area; that force is transferred to the hitch through the leverage ratio of the lift arm and lift rod. The relief valve setting also draws the upper limit: the moment the valve opens, oil returns to the tank and lifting stops.
- Two tractors at the same pressure give different capacities if the arm geometry differs.
- Capacity varies with the measuring point; the value measured at the pin end is higher than the value taken 610 mm behind the pin.
- If the oil level is low or the pump is tired, you will not reach the catalogue value.
Electronic retrofit kits neither increase nor decrease capacity. The LFT20, LFT54 and ELF-812 electronify the control side; the lifting work is still done by the tractor's own hydraulics. If the hitch cannot lift a heavy implement, the solution is not in the kit but in hydraulic maintenance and in comparing the implement weight with the hitch capacity.
The context in which this term is used: Converting a tractor hydraulic lever to electronic control