SAQA All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.
SOUTH AFRICAN QUALIFICATIONS AUTHORITY 
REGISTERED UNIT STANDARD: 

Demonstrate knowledge of capacitors, semiconductor diodes, and rectification 
SAQA US ID UNIT STANDARD TITLE
115238  Demonstrate knowledge of capacitors, semiconductor diodes, and rectification 
ORIGINATOR
SGB Aircraft Maintenance and Overhaul 
PRIMARY OR DELEGATED QUALITY ASSURANCE FUNCTIONARY
-  
FIELD SUBFIELD
Field 06 - Manufacturing, Engineering and Technology Manufacturing and Assembly 
ABET BAND UNIT STANDARD TYPE PRE-2009 NQF LEVEL NQF LEVEL CREDITS
Undefined  Regular  Level 2  NQF Level 02 
REGISTRATION STATUS REGISTRATION START DATE REGISTRATION END DATE SAQA DECISION NUMBER
Reregistered  2018-07-01  2023-06-30  SAQA 06120/18 
LAST DATE FOR ENROLMENT LAST DATE FOR ACHIEVEMENT
2024-06-30   2027-06-30  

In all of the tables in this document, both the pre-2009 NQF Level and the NQF Level is shown. In the text (purpose statements, qualification rules, etc), any references to NQF Levels are to the pre-2009 levels unless specifically stated otherwise.  

This unit standard does not replace any other unit standard and is not replaced by any other unit standard. 

PURPOSE OF THE UNIT STANDARD 
This unit standard will be useful to people employed in, or seeking employment in the aerospace industry who are required to maintain aircraft. This unit standard provides for a basic appreciation of capacitors, semiconductor diodes, and rectification for trainees in the electrical industry.

People credited with this unit standard are able to demonstrate knowledge of capacitors, semi-conductor diodes and rectification; and test semiconductor diodes.

They are able to:
  • Demonstrate knowledge of capacitors.
  • Demonstrate knowledge of semi-conductor diodes and rectification.
  • Test semiconductor diodes. 

  • LEARNING ASSUMED TO BE IN PLACE AND RECOGNITION OF PRIOR LEARNING 
    The credit calculation is based on the assumption that learners are already competent in terms of the following outcomes or areas of learning when starting to learn towards this unit standard:
  • Communications and Mathematical literacy at Level 1, or equivalent competence.
  • In addition learners need to have achieved credit for "Demonstrate knowledge of electrical and electronic components" and "Demonstrate knowledge of electrical safe working practices" or equivalent competence. 

  • UNIT STANDARD RANGE 
    Specific range statements are provided in the body of the unit standard where they apply to particular specific outcomes or assessment criteria. 

    Specific Outcomes and Assessment Criteria: 

    SPECIFIC OUTCOME 1 
    Demonstrate knowledge of capacitors. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Capacitor types are described in terms of their physical construction. 
    ASSESSMENT CRITERION RANGE 
    Capacitor types -include: stacked-plate, rolled, electrolytic, variable, ceramic.
     

    ASSESSMENT CRITERION 2 
    Capacitance is defined in terms of voltage and charge, and symbol and units are stated. 

    ASSESSMENT CRITERION 3 
    The factors influencing capacitance are stated, as is the effect of each when it is increased and decreased. 
    ASSESSMENT CRITERION RANGE 
    Factors influencing capacitance include: area, distance between plates, dielectric permittivity.
     

    ASSESSMENT CRITERION 4 
    Charge is calculated from given values of capacitance and applied voltage, and current and time. 
    ASSESSMENT CRITERION RANGE 
    Q = CV and Q = It.
     

    ASSESSMENT CRITERION 5 
    The time constant for a simple resistance-capacitance circuit is calculated from given data, and charge / discharge curves are sketched for current and voltage. 

    ASSESSMENT CRITERION 6 
    Practical applications are stated for air, paper, mica ceramic, electrolytic, and solid dielectric capacitors, according to industry practice. 

    ASSESSMENT CRITERION 7 
    Capacitance and voltage rating are identified from capacitor markings according to current practice. 

    ASSESSMENT CRITERION 8 
    Combined capacitance of series and parallel connected capacitors is accurately calculated. 

    ASSESSMENT CRITERION 9 
    The regulatory requirements relating to capacitors used for radio and television interference suppression are stated with reasons, according to the relevant national laws. 

    ASSESSMENT CRITERION 10 
    The safety precautions necessary to prevent electric shock from charged capacitors are stated and comply with site policies and procedures. 

    SPECIFIC OUTCOME 2 
    Demonstrate knowledge of semi-conductor diodes and rectification. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    Diode types, and anode and cathode terminals are correctly identified. 
    ASSESSMENT CRITERION RANGE 
    Diode types include: small signal diode, zener diode, power diode.
     

    ASSESSMENT CRITERION 2 
    Diode behaviour under forward and reverse bias conditions is explained with the aid of sketches of the voltage vs. current characteristics. 
    ASSESSMENT CRITERION RANGE 
    Diode types include: small signal diode, zener diode, power diode.
     

    ASSESSMENT CRITERION 3 
    Diode terms are defined, and typical values during normal and abnormal operation are stated. 
    ASSESSMENT CRITERION RANGE 
    Diode terms include: forward bias, voltage drop, reverse breakdown, peak inverse voltage, average forward current, power dissipation, junction temperature, leakage current.
     

    ASSESSMENT CRITERION 4 
    The operation of single phase rectifier circuits is explained with the aid of diagrams, in terms of input and output waveforms, currents, and voltages, and in line with accepted industry definitions. 
    ASSESSMENT CRITERION RANGE 
    Waveforms include: half-wave, centre-tapped transformer full-wave, bridge full-wave.
     

    ASSESSMENT CRITERION 5 
    Examples of three applications other than rectification are stated. 
    ASSESSMENT CRITERION RANGE 
    Examples of applications -include: free wheeling diodes on solenoids, diode matrices in lamp test circuits, voltage reference.
     

    SPECIFIC OUTCOME 3 
    Test semiconductor diodes. 
    OUTCOME RANGE 
    Diode types include: small signal diode, zener diode, power diode. 

    ASSESSMENT CRITERIA
     

    ASSESSMENT CRITERION 1 
    The diode is tested in accordance with industry practice, and results are documented. 
    ASSESSMENT CRITERION RANGE 
    Diode tests include: forward resistance, reverse mode resistance; in-circuit testing of forward voltage drop and reverse leakage current.
     

    ASSESSMENT CRITERION 2 
    Test results are interpreted to determine serviceability in terms of measured versus expected values. 

    ASSESSMENT CRITERION 3 
    The potential for damage to diodes when carrying out insulation resistance, and the procedures employed to prevent such damage, are described in line with site procedures and accepted best practice. 


    UNIT STANDARD ACCREDITATION AND MODERATION OPTIONS 
  • Anyone assessing a learner against this unit standard must be registered as an assessor with the relevant ETQA.
  • Any institution offering learning that will enable achievement of this unit standard must be accredited as a provider through the relevant ETQA by SAQA.
  • Moderation of assessment will be overseen by the relevant ETQA according to the moderation guidelines and the agreed ETQA procedures. 

  • UNIT STANDARD ESSENTIAL EMBEDDED KNOWLEDGE 
    Essential embedded knowledge will be assessed through assessment of the specific outcomes in terms of the stipulated assessment criteria. Candidates are unlikely to achieve all the specific outcomes, to the standards described in the assessment criteria, without knowledge of the listed embedded knowledge. This means that for the most part, the possession or lack of the knowledge can be directly inferred from the quality of the candidate's performance. Where direct assessment of knowledge is required, assessment criteria have been included in the body of the unit standard. 

    UNIT STANDARD DEVELOPMENTAL OUTCOME 
    N/A 

    UNIT STANDARD LINKAGES 
    N/A 


    Critical Cross-field Outcomes (CCFO): 

    UNIT STANDARD CCFO IDENTIFYING 
    Identify and solve problems and make decisions using critical and creative thinking.
  • Note: The ability of the candidate to identify hazardous conditions, assess and take appropriate action. 

  • UNIT STANDARD CCFO WORKING 
    Work effectively with others as members of a team, group, organisation or community.
  • Note: The ability and willingness of the candidate to accept and interpret work instructions correctly and to request assistance with making safe in an appropriate manner as a team member. 

  • UNIT STANDARD CCFO ORGANISING 
    Organise and manage themselves and their activities responsibly and effectively.
  • Note: The preparation for making safe, the candidate must indicate what tools and personnel protective equipment is required and communicate to fellow workers his/her intentions. 

  • UNIT STANDARD CCFO COLLECTING 
    Collect, analyse, organise and critically evaluate information.
  • Note: The ability of the candidate to reconcile the information from the visual examination and constantly evaluate the changing situation. 

  • UNIT STANDARD CCFO COMMUNICATING 
    Communicate effectively, using visual, mathematical and / or language skills in the modes of oral and / or written presentations.
  • Note: The appropriate communication with the relevant personnel with regard to the reporting of hazards and sub-standard conditions will indicate his/her proficiency in effective communication. 

  • UNIT STANDARD CCFO SCIENCE 
    Use science and technology effectively and critically showing responsibility towards the environment and health of others.
  • Note: The use of science and technology is not relevant for this unit standard. 

  • UNIT STANDARD CCFO DEMONSTRATING 
    Demonstrate an understanding of the world as a set of related systems by recognising that problem-solving contexts do not exist in isolation.
  • Note: The ability of the candidate to identify hazard conditions. The effect of non-compliance and deviation from power plant procedures will indicate his/her proficiency in understanding that a specific action or decision taken has more than one effect. 

  • UNIT STANDARD ASSESSOR CRITERIA 
    Assessors should keep the following principles in mind when designing and conducting assessments against this unit standard:
  • Focus the assessment activities on gathering evidence in terms of the main outcome expressed in the title to ensure assessment is integrated rather than fragmented. Remember we want to declare the person competent in terms of the title. Where assessment at title level is unmanageable, then focus assessment around each specific outcome, or groups of specific outcomes.
  • Make sure evidence is gathered across the entire range, wherever it applies. Assessment activities should be as close to the real performance as possible, and where simulations or role-plays are used, there should be supporting evidence to show the candidate is able to perform in the real situation.
  • Do not focus the assessment activities on each assessment criterion. Rather make sure the assessment activities focus on outcomes and are sufficient to enable evidence to be gathered around all the assessment criteria.
  • The assessment criteria provide the specifications against which assessment judgements should be made. In most cases, knowledge can be inferred from the quality of the performances, but in other cases, knowledge and understanding will have to be tested through questioning techniques. Where this is required, there will be assessment criteria to specify the standard required.
  • The task of the assessor is to gather sufficient evidence, of the prescribed type and quality, as specified in this unit standard, that the candidate can achieve the outcomes again and again and again. This means assessors will have to judge how many repeat performances are required before they believe the performance is reproducible.
  • All assessments should be conducted in line with the following well documented principles of assessment: appropriateness, fairness, manageability, integration into work or learning, validity, directness, authenticity, sufficiency, systematicity, openness and consistency.

    The following particular issues should be taken into consideration when assessing against this unit standard:
    All tasks are carried out in accordance with enterprise procedures, the enterprise being the organisation carrying out the work. Enterprise procedures referred to in this unit standard are the applicable procedures found in the following:
  • Enterprise exposition;
  • Manufacturer publications;
  • Government and local body legislation;
  • Airworthiness authority requirements. 

  • REREGISTRATION HISTORY 
    As per the SAQA Board decision/s at that time, this unit standard was Reregistered in 2012; 2015. 

    UNIT STANDARD NOTES 
    N/A 

    QUALIFICATIONS UTILISING THIS UNIT STANDARD: 
      ID QUALIFICATION TITLE PRE-2009 NQF LEVEL NQF LEVEL STATUS END DATE PRIMARY OR DELEGATED QA FUNCTIONARY
    Elective  48861   National Certificate: Aircraft Maintenance and Overhaul  Level 4  Level TBA: Pre-2009 was L4  Passed the End Date -
    Status was "Reregistered" 
    2016-12-31  TETA 


    PROVIDERS CURRENTLY ACCREDITED TO OFFER THIS UNIT STANDARD: 
    This information shows the current accreditations (i.e. those not past their accreditation end dates), and is the most complete record available to SAQA as of today. Some Primary or Delegated Quality Assurance Functionaries have a lag in their recording systems for provider accreditation, in turn leading to a lag in notifying SAQA of all the providers that they have accredited to offer qualifications and unit standards, as well as any extensions to accreditation end dates. The relevant Primary or Delegated Quality Assurance Functionary should be notified if a record appears to be missing from here.
     
    NONE 



    All qualifications and part qualifications registered on the National Qualifications Framework are public property. Thus the only payment that can be made for them is for service and reproduction. It is illegal to sell this material for profit. If the material is reproduced or quoted, the South African Qualifications Authority (SAQA) should be acknowledged as the source.