ELM Basic machines for extra-low voltage

The experiments use the components of the Electrical Machine Teaching Model system and operate with protective extra-low voltage. All machines are mounted on a base unit that is arranged vertically in the experiment frame.

Objectives

• Recognising basic physical principles
• Recording machine characteristics
• Introduction to drive technology
• Use of simple tools (spanners, oil cans etc.)

With this equipment, direct current, alternating current, and three-phase current machines are assembled from a few manageable individual parts. The functional machines show the different combinations of the stators and rotors and allows for inspections of various snubber (circuit) types. Despite the example set by the electrical machine teaching model, physical processes and typical behaviours of large machines can be demonstrated. The machines are mounted on a connection base unit and with special support overlays. The open design of the machines allows the individual functional parts to be monitored during operation. All attempts are run only with non-hazardous protective extra-low voltage. As well as conventional machine types, the basic features of linear motors are also covered. Rotating field machines with permanently excited rotors from rare earth metals (high-efficiency rotors) are new.

All functions of the Power Analyser CASSY can be operated quickly and directly via the display, the rotary wheel and the buttons on the unit. All settings and measurement results can be saved on the unit and quickly called up again later or simply downloaded.

In addition, the Power Analyser CASSY is fully controllable in real time via RJ45 Ethernet, W-LAN and USB-C interfaces.

These interfaces can be used by the following software:

• CASSY Lab 2 for drives and energy systems,
• MATLAB® and LabVIEW ™
• Lab Docs Editor Advanced

The following integrated servers are available in the Power Analyser CASSY for the local media connection of at least four end devices simultaneously.

For more details, see product data of Power Analyser CASSY (catalogue no. 727100 or 727101).

The equipment includes safe laboratory experiments with safe extra-low voltage. The experiments are carried out with a manual in printed or electronic form.

The target group is trainees at vocational schools as well as students in the first semesters of engineering. The experiments are designed as an introduction at a lower to intermediate learning level.

For further deepening we recommend the following equipment:

• E2.1.1.2 ELM Linear motor for extra-low voltage
• E2.1.1.3 ELM Efficiency Machines for Extra-Low Voltage

Topics

• AC generators with permanent magnet
• How terminal voltage depends on speed and load
• Determination of neutral zone
• Three-pole rotors/twelve-pole rotors
• Generator with shunt excitation
• Compound-wound generators
• AC generators
• Three-phase generators
• Generator with load in star circuit with and without neutral conductor
• Delta circuit for a generator
• DC motors
• Commutation
• Motors with separate excitation
• Shunt-wound/series-wound/compound-wound motors
• AC motors
• Universal motors
• Single-phase synchronous and asynchronous (induction) motors
• Starting motors
• Single-phase asynchronous motor with capacitive/resistive auxiliary phase
• Rotating fields
• Reversal of rotational sense
• Three-phase motors
• Three-phase squirrel cage rotors
• Star and delta circuits
• Three-phase slip-ring rotors
• Three-phase synchronous motor