Some Bogballe spreaders provide start-up and con- tinuous calibration checks to maintain the correct flow and application rate. An accelerometer elimi- nates ‘false’ readings caused by a rough field surface.
GPS boundary on/off control
Judging by eye when it’s best to manually switch on the spinners of a fertiliser broadcaster is no easy task. The same applies when switching them off again approaching the headland. After all, a spinner broadcaster throws fertiliser to the rear as far as to the side, so the switch off point when reaching a headland is different from the switch on
point when starting the next run. Over-dosing on headlands and or under-dosing parts of the crop is the inevitable consequence. GPS-guidance optimises this, with software capable of shifting the on-off point when necessary to take account of the differing spreading characteristics of differ- ent fertilisers. At angled head- lands, some adjustment of
Monitoring individual discs
One shortcoming of weighing systems on gravity-fed broad- casters, is that they cannot take account of variation in flow rate on just one side of the spreader. Caused by a partial blockage of the outlet, for example. When that occurs, both hopper outlets will be adjusted. This results in one side under-dosing slightly and the other side over-dosing. The Electronic Mass Flow Control (EMC) system developed by Rauch overcomes that limitation. EMC monitors and controls the flow to each disc individually. It exploits the fact that fertiliser
flow rate is proportional to the drive torque of the spreading discs, regardless of the type of fer- tiliser involved. On Rauch (and Kuhn) spreaders with hydraulic disc drive, the system measures hydraulic pressure either side of the motor. Where a mechanical disc drive is used, sensors proven on battery-assisted bicycles meas- ure the torque at the drive shaft of each spreading disc. In both cases, EMC software detects any varia- tions and then makes a correction to the relevant hopper slide, as often as once a second. When tested at the Saaten Union
On spread- ers with me- chanical disc drive, the Rauch EMC system measures torque at the drive shaft to de- tect and cor- rect changes in fertiliser flow rate.
research station in France, the system delivered less than 1%
variation from the required application rate.
▶ FUTURE FARMING | 24 May 2019 23
working width minimises over- appli cation. Either by slowing and thereby reducing the throw of hy- draulically-driven discs, or by al- tering the feed-on point where discs are driven mechanically. Apart from fertiliser savings there is the attraction of reduced opera- tor workload and fatigue over a long day.
Spread pattern from a Vicon twin disc broadcaster showing the ref- erence point for turning the spreader on and off at head- lands.
PHOTO: RAUCH
PHOTO: KVERNELAND
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52
