UEEEL0019 - Solve problems in direct current (d.c.) machines
Nominal hours
Location
Prerequisites
UEEEL0021 - Solve problems in magnetic and electromagnetic devices; and
UEECD0043 - Solve problems in direct current circuits; or
UEECD0044 - Solve problems in multiple path circuits; and
UEECD0046 - Solve problems in single path circuits
(Or equivalent to be determined by unit coordinator)
Co-requisites
(Corequisite units must be studied concurrently with this unit)
Overview
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
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, 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
*generators, including:
*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
*calculating generated and terminal voltage of a d.c. shunt generator
*applying Fleming’s left-hand rule for motors and right-hand rule for generators
*motors, basic operation of a motor
*circuit diagrams and characteristics of the different types of d.c. motors
*effect of back emf in d.c. motors
*equivalent circuit for the types of d.c. motors
*operation of a motor and its energy flow
*safety risks associated with using motors (including risks of series d.c. motors)
*torque as the product of the force on the conductors and the radius of the armature/rotor
*calculating force and torque developed by a motor
*types of d.c. motors and their applications
*machine efficiency, including:
*efficiency characteristic of a d.c. machine and the conditions for maximum efficiency
*losses that occur in a d.c. machine
*methods used to determine the losses in a d.c. machine
*calculating losses and efficiency of a d.c machine
*methods used to maintain high efficiency
*safety considerations for inductive loads
*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):