Key and critical concepts you will learn:

On completion of this module, you must be able to:

• Completely disassemble a three-phase motor.
• Do a complete mechanical and electrical inspection and test on all the relevant components and correct any faults that are detected.
• Re-assemble the motor correctly, test it and put it back in service

During this process you must adhere to certain specified required as listed in the Module.
You will be assessed, when you are confident that you may achieve the outcomes as listed, to determine your competence as measured against the required criteria. This assessment will be in line with accepted best practices regarding assessment.
A practical and/or theoretical test will be set at the end of the module and must be completed without using references.

• The correct procedures must be followed to clean, mark and disassemble the motor.
• Bearings must be removed and refitted, using correct procedures learned in modules BIF, BRR -1, BRR- 2 and BRR- 3.
• Cleaning, examining and testing of the components must be done correctly and in accordance with these notes.
• The motor must be reassembled, using the correct procedures and without damage to components.
• The reassembled motor must be tested and test-run and must be in good working order at the completion if the overhaul.

Tools, consumables, equipment and machinery required:

• Three phase induction motor
• Piece of wood or copper punch
• Soft hammer
• Set of spanners
• Allen key set
• Workbench

Prerequisite modules:

• Safe use of hand skills

Additional resources:

• In-company Standard Operating Procedures
• Subject matter experts

Key and critical concepts which you will learn:

• Explain the difference between auto transformers and ordinary power transformers.
• Briefly explain how transformers are cooled.
• Explain the purpose of instrument transformers and how they are usually rated.
• Explain the basic difference between a single phase and a three-phase transformer.
• Explain, with the aid of simple diagrams, the two methods of connecting the windings of a transformer, and the relationship between the voltages and currents in the two methods.
• Explain, with the aid of labelled diagrams, the four methods of connecting the primary and secondary windings of a three-phase transformer.
  • Draw the connection diagram of a three-phase auto-transformer

Tools, consumables, machinery and equipment required:

• Module book / learning material
• Pen
• Booklet to make notes
• Different types of transformers including autotransformer

Related modules:

• TT-1

Application:

• Any electrical work environment where you need to transmit power from one station to another, whenever you need to step up or down the voltage

Additional resources:

• Subject matter experts
• In-company Standard Operating Procedures

Key and critical concepts which you will learn:

• Explain the basic construction of a three-phase alternating current generator (alternator), using schematic diagrams.
• Make a schematic drawing of the voltage graph of a three-phase AC supply, showing the correct phase displacement angle.
• Briefly explain, with the aid of a schematic diagram, how power is transmitted from the power station to the end-user.
• Explain why AC supplies are transmitted at a high voltage.
• Explain, with the aid of simple diagrams, the different transformer connections used to obtain three-phase, three-wire balanced systems and three-phase, four-wire distribution systems.
• Explain how a 220-volt AC supply for domestic use is obtained from a 380-volt AC supply.

Tools, consumables, machinery and equipment required:

• Module book / learning material
• Pen
• Booklet to make notes

Related modules:

• PST-1

Application:

• Industries which generate electricity like but not limited Eskom, Roshcon, etc.

Additional resources

• Subject matter experts
• In-company Standard Operating Procedures