This thesis presents a development of a device as an improvement of an already existing machine for spreading hay in a hayloft. At the beginning the original means of its control, the way of setting the operating area is presented. This is accomplished by using contactors, limit switches and mechanical limiters that trip them and whose position is set by the user. Problems that arise using such control means are introduced, mainly slowness of the spreader when moving to its starting position where access to mechanical limiters is possible. High summer temperatures and dust in a hayloft are also unpleasant to the user. There certainly are ways of improving that in means of remotely setting the machine’s working area from a separate and cleaner room. Possible ways of detecting position are presented, mainly using encoders and inductive proximity switches. These means are evaluated and the best option is chosen.
The device consists of control and movable unit. The control unit serves mainly as a user interface using a LCD display and a rotary encoder. User uses it to set the working area or to monitor both current positions and the set operating mode of the spreader. Main parts of the movable unit are the power part for switching on the contactors, the part for monitoring supply voltage and connectors for inductive sensors. Common part of both units is communication using RS485 and the Modbus protocol. This thesis also presents the main parts of software of both units in greater detail.
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