This system investigates the operating and standstill behaviour of an electric asynchronous machine with squirrel-cage rotor. Special attention is paid to the termination, the rated values, the efficiency determination and the machine characteristic curve.
Experimental procedures are carried out with industrially manufactured machines. All test machines have a special base for termination to the machine test CASSY 0.3. All measured values of the alternating current machines are recorded with the machine test CASSY. The measured values can be shown directly on the built-in display as a single value, table of a measurement series or diagram. The measurements can be taken without additional software and the measurement data can be saved locally on the device. The machine test CASSY is used to record the characteristics of the test machines. The power supply for the test machines is partly provided directly from the public supply network.
Learning objectives
- Protective measures and electrical safety.
- Setup and commissioning of electrical machines.
- Use of starting circuits.
- Machine efficiency.
- Assessment of characteristic curves of electrical machines.
Asynchronous machines a squirrel cage rotors are widely used. These are particularly low-maintenance motors. They are increasingly replacing direct current machines with frequency converters. Asynchronous machines with squirrel cage rotors are used as motors and rarely as generators. The asynchronous motor in this configuration has the suffix 230 / 400 V, which corresponds to the rated voltage of the motor. Only with this voltage does the motor have to be duty cycled in a 230 V / 400 V star and therefore no starting can take place in the star-delta starting.
Asynchronous machines as squirrel cage rotors are widely used. These are particularly low-maintenance motors. They are increasingly replacing direct current machines with frequency converters. Asynchronous machines with squirrel cage rotors are used as motors and rarely as generators. The asynchronous motor in this configuration has the suffix 230 / 400 V, which corresponds to the rated voltage of the motor. Only with this voltage does the motor have to be duty cycled in a 230 V / 400 V star and therefore no starting can take place in the star-delta starting.
Asynchronous machines as squirrel cage rotors are widely used. These are particularly low-maintenance motors. They are increasingly replacing direct current machines with frequency converters. Asynchronous machines with squirrel cage rotors are used as motors and rarely as generators. The asynchronous motor in this configuration has the suffix 230 / 400 V, which corresponds to the rated voltage of the motor. Only at this voltage must the motor be clocked in a 230 V / 400 V star and therefore no star-delta starting is possible.
Highlights
- To protect against overheating, the stator windings of the test machines are equipped with thermal detectors.
- In the event of overheating, the machine test CASSY 0.3 system switches off the load of the test machine, thus maintaining air cooling. This prevents damage to the test machines.
- The test machines have a didactic terminal board with the winding diagram printed on it.
- All winding ends are led out to safety sockets (4 mm) on the terminal board.
- Computer-aided data acquisition provides meaningful measurement results.
- The arrangement of the 4 mm safety sockets complies with the standards for industrial motors.
Measuring and media system
Machine Test CASSY
The machine test CASSY 0.3 can be quickly operated in all functions directly via the display, the rotary knob and the buttons on the device. All settings and measurement results can be saved on the device and quickly called up again later or simply downloaded.
In addition, the machine test CASSY 0.3 can be fully controlled in real time via the RJ45 Ethernet, W-LAN and USB-C interfaces.
These interfaces can be used by the following software:
- CASSY Lab 2 for drive and energy technology,
- MATLAB and LabVIEW,
- Lab Docs Editor Advanced.
The following integrated servers are available in the machine test CASSY 0.3 for the local media connection of at least four end devices simultaneously.
Further information can be found in the product documentation 7731901 machine test CASSY 0.3.
Target group
The target group is industrial trainees and students specialising in electrical engineering. The course offers tests at an intermediate level for the vocational school and at the same time provides the necessary insights into the machine behaviour for a scientific interpretation in the bachelor training. The media connection makes the experiments suitable for demonstration in the classroom or a lecture theatre.
The following equipment includes extended experiments with asynchronous machines.
- E2.2.4.2 Squirrel cage rotor 230/400.
- E2.2.4.3 Squirrel cage motor 230/400 IE3.
- E2.2.4.4 Slip ring rotor.
- E2.2.4.5 Squirrel cage rotor D.
- E2.2.4.6 Multifunction machine.
- E2.5.3.3 Drives with didactic frequency inverter.
- E2.5.3.4 Drives with industrial frequency inverter.
- E2.5.4.2 Direct starting or starting with a soft starter of an asynchronous motor under load.
- E2.5.4.4 Operating behaviour of variable-speed asynchronous motors under load.
- E2.6.2.2 AC servo with industrial asynchronous machine.
