In Automation we also need to manage and control the motors in AC and DC and to monitor some industrial plant.
For that reason De Lorenzo has developed trainers to also deepen this field realizing special ones with safety low voltage that allow the final user to learn how to manage different kinds of three-phase AC motors, how to control a DC motor complete with a brake in open and closed-loop and how to protect them using devices of the most used in the industrial field.
These trainers are recommended for high schools.
With this board, the students can perform experiments with components normally used in industrial electrical environment.
The components on the front panel can be wired together through 2 mm terminals for what concerns the low voltage controls, and through 4 mm safety terminals for the connections to the mains or for further applications.
All the components are identified through clear synoptic diagrams showing their types and symbols.
On the rear side of the board, there are switches to allow for the introduction of faults by the teacher.
The board, allowing the simulation of starting systems for the motors with squirrel cage rotor, is equipped with a clear synoptic diagram that shows through terminals: the push-buttons, the thermal relay contacts, the contactor coils and the signaling lamps.
The system, besides the board, includes a three-phase asynchronous motor supplied at the reduced voltage of 42 V, complete with educational base and terminals that make easy the connection to the simulation panel.
The speed meter, connected to an opto-encoder, allows measuring the rotation speed of the motor.
Besides, a magneto-thermal switch and an emergency key allow the immediate interruption of the supply circuit in case of overload or short-circuit.
The system has been designed for the study of programmable logic control techniques in the control of the speed of a separately excited dc motor. The speed regulation includes two control loops: hardware current loop with overcurrent limiting and speed loop with external PLC control. Speed measuring with a tacho generator or with an opto-encoder via frequency/voltage converter.
Speed reference set by means of potentiometer or selector switches and under PLC control. The PI controller modulates the PWM circuit that drives the power stage consisting of switching transistor. Possibility of acceleration and deceleration ramps programming. Pointer meters for motor speed, voltage and armature current; connection to PLC through terminals or connectors.