UEEEL0024 - Test and connect alternating current (a.c.) rotating machines

Unit code: UEEEL0024 | Study level: TAFE
Nominal hours
40
Location
Sunshine
Prerequisites
(Or equivalent to be determined by unit coordinator)
Co-requisites
(Corequisite units must be studied concurrently with this unit)
Overview
Enquire

Overview

This unit involves the skills and knowledge required to test and connect alternating current (a.c.) rotating machines. It includes safe working practices, ascertaining correct operation of a.c. machines and solving problems as they apply to servicing, fault finding, installation and compliance work functions
The skills and knowledge described in this unit require a licence or permit to practice in the workplace where work is carried out on electrical installations which are designed to operate at voltages greater than 50 volt (V) a.c. or 120 V direct current (d.c.).

Assessment

For Melbourne campuses

Assessment tasks will be designed to reinforce & extend knowledge and skill competence within set & controlled parameters in accordance with each unit’s learning outcomes & performance criteria requirements, including the setting of work based practical application tasks designed to provide evidence of competence outcomes, within periodic and scheduled timelines.
Students will be expected to demonstrate the following required skills:

  • applying work health and safety (WHS)/occupational health and safety (OHS) workplace procedures, including:
  • identifying and assessing hazards and risks, and implementing control measures
  • checking circuits are isolated in accordance with workplace procedures and regulatory requirements
  • applying testing and connecting techniques in alternating current (a.c.) rotating machines, including:
  • connecting, running and reversing the direction of a single phase motor and a three phase motor
  • applying testing and connecting techniques in alternating current (a.c.) roatating machines, inculding:
  • connecting three phase induction motor in both star and delta connections
  • connecting, running and reversing the direction of a three phase motor
  • determining the operating parameters of existing machines
  • altering an existing machine connection or circuit to comply with specified operating parameters
  • developing machines/circuits to comply with a specified function and operating parameters
  • determining the cause of low efficiency in an existing machine
  • performing insulation resistance, continuity and winding identification tests
  • identifying faults/faulty components in single and three phase motors
  • testing insulation resistance of a three phase induction motor prior to connection to the supply
  • testing winding resistance (ohmic value and continuity) of a three phase induction motor prior to connection to the supply
    *applying sustainable energy principles and practices
    *completing problem-solving activities documentation.

Students will also be expected to demonstrate the following knowledge:
*operating principles of three phase induction motors, including:

  • speed of rotation of a rotating magnetic field
  • relationship between the rotor speed, slip and rotor frequency
  • basic principle of operation of an induction motor
  • motor action in a generator and generator action in a motor
    *three phase induction motor construction, including:
  • basic component parts of a three phase induction motor
  • types of rotors (standard and wound) used in three phase induction motors
  • connections for three phase induction motor in both star and delta
    *three phase induction motor characteristics, including:
  • relationship between torque, speed, and power and interpretation of speed/torque curves of induction motors
  • squirrel cage motors operating characteristics conditions necessary for an induction motor to produce maximum torque
  • operating characteristics of an induction motor from nameplate information and by measurement
  • induction motors efficiency and minimum energy performance standards (MEPS)
  • full load efficiency and power factor of induction motors
    *split phase - single phase motors, including:
  • identification of split phase induction motors
  • principles of operation of a split phase induction motor
  • construction and basic characteristics of a split phase induction motor
  • applications of split phase induction motors
    *single phase motors – capacitor and shaded pole types, including identification of single phase induction motors, including:
  • capacitor start/capacitor run, permanent split capacitor (PSC) and shaded pole
  • principles of operation of each motor type listed above
  • operating characteristics and typical applications of each motor type listed above
  • reversing the direction of rotation of each of the motors listed above
    *single phase motors – series universal, including:
  • principles of operation of a series universal motor
  • identification and functions of each of the basic parts of a series universal motor
  • operating characteristics and typical uses for a series universal motor
    *motor protection, including:
  • reasons why motor protection is required
  • requirements of the AS/NZS 3000 with regards to motor protection
  • types of motor overload protection
  • operating principles of thermal cut-out devices, thermal and magnetic motor protection devices for single and three phase motors
  • electrical features of motor protection high rupturing capacity (HRC) fuses
  • effects of undervoltage and overvoltage on motors and motor circuits
  • effects of repetitive starting and/or reversing on motors
  • special requirements for motor protection in high humidity or moist environments, high temperature areas and corrosive atmospheres
  • operating principles of phase failure protection
  • selecting suitable protective devices for a given motor and starter combination
    *three phase synchronous machines- operation principles and construction, including:
  • power transfer diagram of an a.c. synchronous machine
  • generation of a sinusoidal waveform
  • operation of a synchronous alternator
  • operation of a synchronous motor
  • principles of operation of an asynchronous generator (induction generator)
  • identification of main parts of a synchronous alternator/motor
  • methods used to provide the excitation of a synchronous alternator/motor
  • block diagram of an alternator voltage regulator
  • advantages gained by the parallel operation of alternators
  • starting methods of synchronous motors
    *alternators and generators, including:
  • effects on the generated voltage of variations in excitation
  • effects on generated voltage of variations in load current and power factor
  • identification of characteristic curves of an alternator
  • types of prime movers used with single and three phase portable/standby alternators
  • manual operation of single and three phase portable/standby alternators
  • ratings of single and three phase portable/standby alternators
  • applications of single and three phase portable/standby alternators
  • construction details of single and three phase portable/standby alternators
  • common faults found in portable/standby alternators
  • parallel connection
  • load sharing
  • standby generators and associated arrangements
    *safe testing methods for locating faults in low voltage (LV) a.c machines, including:
  • insulation resistance
  • coil resistance
  • centrifugal switch
  • capacitor
  • bearing wear
  • locked rotor
  • load
  • thermal overload
  • machine controls
    *mechanical faults and associated symptoms that occur in LV a.c rotating machines, including:
  • bearings
  • fans
  • bent shaft
  • locked rotor
  • blocked air vents
  • centrifugal switches
  • environmental factors
    *faults on driven loads and couplings and their consequences, including:
  • slipping belts
  • poorly aligned coupling (shims)
  • vibration
  • loads bearing failing
  • load stalling
    *electrical faults and associated symptoms that occur in LV a.c rotating machines, including:
  • open and partially open circuit winding
  • short and partially short circuit winding
  • open circuit rotor
  • burnt out winding
  • coil shorted to frame
  • relevant manufacturer specifications.

Required reading

The qualified trainer and assessor will provide teaching and learning materials as required in the form of workbooks produced by Victoria University and/or via the Victoria University e-learning system.

As part of a course

This unit is studied as part of the following course(s):

Certificate III in Electrotechnology Electrician
UEE30820 | Certificate iii | Duration:

Refer to the course page for information on how to apply for the course. VU takes care to ensure the accuracy of this unit information, but reserves the right to change or withdraw courses offered at any time. Please check that unit information is current with the Student Contact Centre.

Search for units, majors & minors