Depth Repeatability
The same control command giving the same working depth on every pass. When repeatability drops, depth differences appear from row to row in the field; emergence uniformity in seeding, and fuel consumption and work quality in tillage, are directly affected.
The factors that spoil repeatability are mostly mechanical: worn pin sockets, a lift rod with play, a slackened quadrant spring and the increased internal leakage of hot hydraulic oil. On the electronic side, what is decisive is whether the command produces the same position every time.
- With a manual quadrant, repeatability depends on the operator putting the lever in the same notch.
- As the oil heats up the linkage settles slightly lower under load; the depth measured in the morning and in the afternoon can differ.
- Always measure from the same reference: for example the distance between the wheel track surface and the implement tip.
The contribution of electronic control here is that it takes the command out of the operator's hand. The LFT20 and LFT54 pull the cable to the same stroke every time (60 mm / 50 mm); the ELF-812, in position mode, aims to return to the selected height. This does not eliminate mechanical play, but it clearly reduces operator-induced deviation.
Context in which this term is used: Converting a tractor hydraulic lever to electronic control