This unit involves the skills and knowledge required to determine correct operation of direct current (d.c.) machines and provide solutions as they apply to electrical installations and equipment.
It includes working safely, the use of testing and measuring devices, and providing solutions derived from measurements and calculations to predictable problems in d.c. machines.
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) alternating current (a.c.) or 120 V d.c.
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, incl 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:
*complying work health and safety (WHS)/occupational health and safety (OHS) requirements, including:
*identifying safety risks associated with using generators, motors. rotating machinery and inductive loads
*confirming isolation of circuits
*connecting and testing a direct current (d.c.) machine
*identifying of faults in a machine from electrical measurements
*recording electrical measurements and comparing with nameplate ratings
*reversing the direction of rotation of a d.c motor
*ensuring all work complies with relevant industry standards and legislation
*completing required documentation and reporting
Students will also be expected to demonstrate the following knowledge:
*rotating machine construction, testing and maintenance, including:
*care, maintenance and testing processes for rotating machines
*components of a d.c. machine
*difference between a generator and a motor in terms of energy conversion
*nameplate of a machine
*safety risks associated with using rotating machinery
*types of faults in electric machines
*basic operation of a d.c. generator
*equivalent circuit for a d.c. generator
*importance of residual magnetism for a self-excited generator
*load characteristics of a d.c. generator
*methods of excitation used for d.c. generators
*open circuit characteristics of d.c. generators
*prime movers, energy sources and energy flow used to generate electricity
*reversing the polarity of a d.c. generator
*types of d.c. generators and their applications
The qualified trainer and assessor will advise students of class notes, reading materials produced by VU Polytechnic and further support via VU Polytechnic e-learning system and/or in person.
This unit is studied as part of the following course(s):