The evidence guide provides advice on assessment and must be read in conjunction with the performance criteria, required skills and knowledge, range statement and the Assessment Guidelines for the Training Package.

Overview of assessment

A person who demonstrates competency in this unit must be able to perform electro-discharge (EDM) machining operations. Competency in this unit cannot be claimed until all prerequisites have been satisfied.

Critical aspects for assessment and evidence required to demonstrate competency in this unit

Assessors must be satisfied that the candidate can competently and consistently perform all elements of the unit as specified by the criteria, including required knowledge, and be capable of applying the competency in new and different situations and contexts.

Context of and specific resources for assessment

This unit may be assessed on the job, off the job or a combination of both on and off the job. Where assessment occurs off the job, that is the candidate is not in productive work, then an appropriate simulation must be used where the range of conditions reflects realistic workplace situations. The competencies covered by this unit would be demonstrated by an individual working alone or as part of a team. The assessment environment should not disadvantage the candidate.

This unit could be assessed in conjunction with any other units addressing the safety, quality, communication, materials handling, recording and reporting associated with electro-discharge (EDM) machining operations or other units requiring the exercise of the skills and knowledge covered by this unit.

Method of assessment

Assessors should gather a range of evidence that is valid, sufficient, current and authentic. Evidence can be gathered through a variety of ways including direct observation, supervisor's reports, project work, samples and questioning. Questioning techniques should not require language, literacy and numeracy skills beyond those required in this unit of competency. The candidate must have access to all tools, equipment, materials and documentation required. The candidate must be permitted to refer to any relevant workplace procedures, product and manufacturing specifications, codes, standards, manuals and reference materials.

Guidance information for assessment

Required skills

Look for evidence that confirms skills in:

following relevant safety procedures

obtaining and interpreting relevant drawings, job instructions and specifications

selecting correct electrode to ensure that the finished product conforms to specification

determining the coordinates of the work pieces relative to the machine datum

calculating machining parameters necessary to achieve the safe, accurate and efficient machining of the work piece

calculating the surface area of the electrode

positioning work piece and electrode to enable the safe, accurate and efficient machining of the required feature(s)

producing components to specification

checking machined components for conformance with specifications

Required knowledge

Look for evidence that confirms knowledge of:

safety hazards associated with the use of electro-discharge machines

the job requirements

the sequence of operations to achieve the job requirements

the electrode type and geometry required to achieve the specified outcome

the effects of material to be machined on the electrode material and geometry

the procedures for producing electrodes for the electro-discharge machining process

the coordinates of the feature(s) to be machined

the coordinates of the electrode relative to the machine datum

the procedures for operating the electro-discharge machine to produce components

the tools, techniques and equipment appropriate to the checking of machined components

the procedures for checking machined components for conformance to specification

the reasons for selecting the tools, techniques and equipment to be used

The range statement relates to the unit of competency as a whole. It allows for different work environments and situations that may affect performance. Bold italicised wording, if used in the performance criteria, is detailed below. Essential operating conditions that may be present with training and assessment (depending on the work situation, needs of the candidate, accessibility of the item, and local industry and regional contexts) may also be included.

Electrode

Includes all types and grades of graphite electrodes

Job set up

Includes correct use of work holding devices and selection of EDM fluids, spark generation, cycle time, power settings, and dielectric fluids for the requirement of a particular job