9) This provides essential advice for assessment of the unit of competency and must be read in conjunction with the Performance Criteria and the Range Statement of the unit of competency and the Training Package Assessment Guidelines.

The Evidence Guide forms an integral part of this Competency Standard Unit and shall be used in conjunction with all component parts of this unit and, performed in accordance with the Assessment Guidelines of this Training Package.

Overview of Assessment

9.1)

Longitudinal competency development approaches to assessment, such as Profiling, require data to be reliably gathered in a form that can be consistently interpreted over time. This approach is best utilised in Apprenticeship programs and reduces assessment intervention. It is the Industry’s preferred model for apprenticeships. However, where summative (or final) assessment is used it is to include the application of the competency in the normal work environment or, at a minimum, the application of the competency in a realistically simulated work environment. It is recognised that, in some circumstances, assessment in part or full can occur outside the workplace. However, it must be in accord with Industry and, Regulatory policy in this regard.

Methods chosen for a particular assessment will be influenced by various factors. These include the extent of the assessment, the most effective locations for the assessment activities to take place, access to physical resources, additional safety measures that may be required and the critical nature of the competencies being assessed.

The critical safety nature of working with electricity, electrical equipment, gas or any other hazardous substance/material carries risk in deeming a person competent. Hence, sources of evidence need to be ‘rich’ in nature so as to minimise error in judgment.

Activities associated with normal every day work have a bearing on the decision as to how much and how detailed the data gathered will contribute to its ‘richness’. Some skills are more critical to safety and operational requirements while the same skills may be more or less frequently practiced. These points are raised for the assessors to consider when choosing an assessment method and developing assessment instruments. Sample assessment instruments are included for Assessors in the Assessment Guidelines of this Training Package.

Critical aspects of evidence required to demonstrate competency in this unit

9.2)

Before the critical aspects of evidence are considered all prerequisites shall be met.

Evidence for competence in this unit shall be considered holistically. Each element and associated Performance Criteria shall be demonstrated on at least two occasions in accordance with the “Assessment Guidelines – UET12”. Evidence shall also comprise:

A representative body of Performance Criteria demonstrated within the timeframes typically expected of the discipline, work function and industrial environment. In particular this shall incorporate evidence that shows a candidate is able to:

Implement Occupational Health and Safety workplace procedures and practices including the use of risk control measures as specified in the Performance Criteria and range; and

Apply sustainable energy principles and practices as specified in the Performance Criteria and range; and

Demonstrate an understanding of the essential knowledge and associated skills as described in this unit to such an extent that the learner’s performance outcome is reported in accordance with the preferred approach; namely a percentile graded result, where required by the regulated environment; and

Demonstrate an appropriate level of employability skills; and

Conduct work observing the relevant Anti discrimination legislation, regulations, policies and workplace procedures; and

Demonstrated performance across a representative range of contexts from the prescribed items below:

Range of tools/equipment/materials/procedures/workplaces/other variables

Group No

The minimum number of items on which skill is to be demonstrated

Item List

A

Demonstration of at least two (2) downloads from protection relays or recording equipment from each of the following:

Relay panel

Remote location

B

Development of five (5) evaluation reports on power system events including the following:

Interpretation of targets in a substation

Interpretation of fault reports

Interpretation of downloaded event data

Development of valid conclusions and recommendations.

C

At least one occasion

Dealing with an unplanned event by drawing on essential knowledge and associated skills to provide appropriate solutions incorporated in the holistic assessment with the above listed items.

Context of and specific resources for assessment

9.3)

This unit should be assessed as it relates to normal work practice using procedures, information and resources typical of a workplace. This should include:

OHS policy and work procedures and instructions.

Suitable work environment, facilities, equipment and materials to undertake actual evaluation of power system events.

Operational access to relevant plant, protection equipment, event data, scheme drawings and specialised testing equipment

In addition to the resources listed above, in Context of and specific resources for assessment, evidence should show demonstrated competency working at realistic heights above ground i.e. above 3 metres, in limited spaces, with different structural/construction types and method and in a variety of environments.

Method of assessment

9.4)

This Competency Standard Unit shall be assessed by methods given in Volume 1, Part 3 “Assessment Guidelines”.

Note:

Competent performance with inherent safe working practices is expected in the Transmission, Distribution and Rail Traction Industry. This requires that the specified essential knowledge and associated skills are assessed in a structured environment which is primarily intended for learning/assessment and incorporates all necessary equipment and facilities for learners to develop and demonstrate the essential knowledge and associated skills described in this unit.

Concurrent assessment and relationship with other units

9.5)

There are no concurrent assessment recommendations for this unit.

8) Essential Knowledge and Associated Skills (EKAS): This describes the essential skills and knowledge and their level, required for this unit.

Evidence shall show that knowledge has been acquired of conducting evaluation of power system faults within a substation.

All knowledge and skills detailed in this unit should be contextualised to current industry practices and technologies.

KS01-TTS23A Power system substation faults evaluation

Evidence shall show an understanding of power system substation faults evaluation to an extent indicated by the following aspects:

T1 OHS enterprise responsibilities encompassing:

Provisions of relevant health and safety legislation

Principles and practice of effective occupational health and safety management

Management arrangements relating to regulatory compliance

Enterprise hazards and risks, control measures and relevant expertise required

Characteristics and composition of workforce and their impact on occupational health and safety management

Relevance of enterprise management systems to occupational health and safety management

Analysis of working environment and design of appropriate occupational health and safety management systems

Analysis of relevant data and evaluation of occupational health and safety system effectiveness

Assess resources to establish and maintain occupational health and safety management systems.

T2 Power distribution network documentation encompassing:

Requirements for the use of manuals, system diagrams/plans and drawings and for plans such as work method statements for the control of OHS risks

Types and application of power distribution network documentation drawings and documents - wiring and schematic diagrams, drawings and switching symbols, mechanical drawings dealing with the power distribution network, project charts, schedules, graphs, technical manuals and catalogues, instruction/worksheets sheets.

Interpretation of different diagrams and documentation on LV and HV systems - overhead distribution extensions, underground distribution extensions, distribution substation, street lighting system

T3 Measurements and the interpretation and analysis of those measurements related to the plant and/or equipment type encompassing:

Type of measurements - timing, current, voltage, capacitance, inductance, impedance, phase angle, phase shift, resistance, dielectric dissipation factor, frequency, polarisation index, ratio, vector group, temperature

Interpretation and analysis the use of techniques - digital comparison of data, extrapolation, use of graphs and charts, statistics and tables, mathematical calculation of expected values and comparison with manufacturers data and measurements

Techniques in the processes involved in follow-up actions and recommendations resulting from analysis and interpretation of results and measurements.

T4 System components and layouts encompassing:

Distribution system layouts - overhead/underground, urban/rural, HV customers, high rise building systems, three phase lines, single phase lines, SWER systems, spur, parallel and ring systems, typical substation types.

Transmission system layouts - lines, buses, transformers and cables, line/bus layouts including single, double, ring and breaker and half systems, HV crossing methods.

T5 Calculation of fault levels encompassing:

Calculation of fault levels in symmetrical and asymmetrical fault conditions - types of faults, interconnected and radial systems, symmetrical components, representation of voltages and currents, sequence impedances of system plant, calculation/determination of sequence impedance networks, determination of operative sequence impedances, fault or arc impedances, first approximation techniques

Interrupting device capabilities - determination of fault current breaking capability and let through energy capability of fuses and circuit breakers, DC offset and transient condition effects

T6 Protection system types encompassing:

Requirements of a protection scheme - relationship to primary system design, purpose of protection, safety of persons, protection of plant, system instability, system break up, loss of customers, loss of revenue, protection zones, restricted schemes, unrestricted schemes, duplicate protection, local backup protection, remote backup protection, selectivity, discrimination, stability, sensitivity, reliability

Components of a protection scheme - current transformers, potential transformers, summation current transformers, interposing transformers, multitapped transformers, all-or-nothing relays, induction relays, balanced beam relays, directional relays, biased relays, solid state relays, microprocessor based relays, gas relays, thermal sensors, hardwired communication, powerline carriers systems, microwave systems, fibre optic systems, need for isolation, need for interfacing

Protection applied to buses - overload, differential, earth leakage, structure leakage, combined schemes, protection overlap

Protection applied to transformers - biased differential, gas, winding temperature, oil temperature

Protection applied to single/radial lines - overcurrent, earth leakage, slow earth leakage, distance, auto reclose, sectionalising, over voltage

Protection applied to interconnected lines - overcurrent, pilot wire, directional, directional overcurrent, current differential, phase comparison, current comparison, distance, impedance, admittance, offset

T7 Detailed operation and setting of discrete protection systems encompassing:

Earth fault protection - master earth leakage schemes, sensitive earth fault relays and schemes, residual earth fault scheme, core balance earth fault scheme, frame/structure earth leakage scheme, time graded discrimination, backup protection

Overcurrent protection - feeder overcurrent protection, instantaneous overcurrent schemes, inverse timed overcurrent schemes, types and location of components of an overcurrent scheme, CT summation, time graded discrimination, backup protection

Alarms and controls - auxiliary relays, voltage regulating relays, line drop compensation, gas relay types, gas relay scheme operation and setting, over temperature schemes

T8 Detailed operation of interdependent protection systems encompassing:

Overcurrent and earth leakage schemes including intertripping, interlocking and blocking - logic mapping, master control, electromechanical, electronic, shading coils

Pilot wire, phase comparison - opposed voltage schemes, circulating current schemes, location of components of a scheme, pilot supervisory techniques,

Load shedding, voltage control, parallel operation, load rejection

Busbar Protection and CB failure protection

Reclose systems - applications, single shot, multishot, blocking schemes, synchronisation checking.

T9 Detailed operation of complex protection systems encompassing:

Distance - characteristics, electromechanical, electronic, impedance, mho, offset mho, switched schemes, non-switched schemes, blocking schemes, bus zone

Differential, transformer differential, bus overcurrent - principles, feeder protection, transformer protection, bias systems, harmonic restraint, CT connections, bus protection, low impedance schemes, high impedance schemes, bus overcurrent schemes, generator protection, CT connections, special considerations, digital systems

Types of revenue metering

Applications of SCADA

Complex protection systems for communications

Harmonic control

Point on wave switching

10) This relates to the unit of competency as a whole providing the range of contexts and conditions to which the Performance Criteria apply. It allows for different work environments and situations that will affect performance.

This Competency Standard Unit shall be demonstrated in relation to evaluating power system events that effect substation equipment and may include the following: secondary equipment, feeder outage, disturbance recorders, alarms, transformers, circuit breakers, DC supplies, SCADA and busbars.

The following constants and variables included in the element/Performance Criteria in this unit are fully described in the Definitions Section 1 of this volume and form an integral part of the Range Statement of this unit:

Appropriate and relevant persons (see Personnel)

Appropriate authorities

Appropriate work platform

Assessing risk

Assessment

Authorisation

Confined space

Diagnostic, testing and restoration

Documenting detail work events, record keeping and or storage of information

Drawings and specifications

Emergency

Environmental and sustainable energy procedures

Environmental legislation

Environmental management documentation

Established procedures

Fall prevention

Hazards

Identifying hazards

Inspect

Legislation

MSDS

Notification

OHS practices

OHS issues

Permits and/or permits to work

Personnel

Quality assurance systems

Requirements

Testing procedures

Work clearance systems