Carry out routine inspection and servicing on distribution instrument transformers below 33kV

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1 Page 1 of 5 Carry out routine inspection and servicing on distribution instrument transformers below 33kV Level 4 Credits 7 Purpose People credited with this unit standard are able, for distribution instrument transformers below 33kV, to: prepare for routine service; carry out routine inspections and diagnostic tests; carry out servicing; record routine inspection and servicing; and return equipment to service. Subfield Domain Status Electricity Supply Electricity Supply - Power System Maintenance Registered Status date 27 April 1998 Date version published 21 November 2008 Planned review date 31 December 2009 Entry information Accreditation Standard setting body (SSB) Prerequisites: Unit 14287, Use and maintain test instruments used within the high voltage electrical industry; Unit 14700, Apply and remove safety measures in an electricity supply environment; Unit 14701, Manage electricity supply work control systems; Unit 12296, Apply earths to and remove earths from electrical conductors, plant and equipment; or demonstrate equivalent knowledge and skills. Evaluation of documentation and visit by NZQA and industry. Electricity Supply Industry Training Organisation Accreditation and Moderation Action Plan (AMAP) reference 0120 This AMAP can be accessed at Special notes 1 This unit standard can be assessed in a workplace environment, or in a training or educational environment if simulated equipment response and examples are able to be provided, or in a combination of both environments.

2 Page 2 of 5 2 Performance and work practices in relation to the elements and performance criteria must comply with all current legislation, especially the Electricity Act 1992, and any regulations and codes of practice recognised under that statute; the Health and Safety in Employment Act 1992; and the Resource Management Act Electricity supply industry codes of practice and documented industry procedures include the Safety Manual Electricity Industry (SM-EI) (2004) Wellington: Electricity Engineers Association. A full list of current legislation and industry codes is available from the Electricity Supply Industry Training Organisation, PO Box 1245, Hamilton The phrase in accordance with industry requirements is implicit in all elements and performance criteria in this unit standard. 4 Industry requirements include all asset owner requirements; manufacturers specifications; and enterprise requirements which cover the documented workplace policies, procedures, specifications, business, and quality management requirements relevant to the workplace, training or educational environment in which assessment is carried out. 5 Core electrical theory is essential knowledge underpinning the performances required by this unit standard. 6 The range of this unit standard is limited to carrying out preventative maintenance and replacement and/or repairs to distribution instrument transformers below 33kV, normally applied at electricity distribution substations. 7 The following terms and abbreviations relate to this unit standard: CTs refers to Current transformers VTs refers to Voltage transformers. Elements and performance criteria Element 1 Prepare for routine service on distribution instrument transformers below 33kV. 1.1 The scope of work and equipment are identified and selected in accordance with servicing procedures. may include but is not limited to associated client or enterprise check and/or inspection lists and procedures for instrument transformers, CTs, VTs. 1.2 The defect history and plant history records are scrutinised for indications of servicing needs. may include but is not limited to known defects, operator reports, client special service requests, oil analysis, dissolved gas analysis, thermography tests.

3 Page 3 of The required access permit, or recognised equivalent, is received, checked, and signed. may include but is not limited to a careful check of the isolations to ensure the access permit, or recognised equivalent, provides a safe work environment. 1.4 All safety measures are in place to eliminate, minimise or control hazards in the permit area. includes inspection of the safe working zone to ensure the safe work area has been correctly delineated and provides a safe work environment. 1.5 The work party is fully briefed on the equipment to be worked on, work to be done, safe working zone and safety features in place, and has signed the access permit or its approved equivalent. includes the ability to resolve any concerns the work party may have over the isolations and the delineation of the safe work area. All communication with the work party must be clear and unambiguous. Element 2 Carry out routine inspections and diagnostic tests. 2.1 People and equipment are resourced for the required work. may include but is not limited to people, tools, spares, materials, inspection sheets, procedure sheets, diagnostic test equipment. 2.2 Inspection and diagnostic tests are completed in accordance with the selected procedures. may include but is not limited to resistance of winding, primary injection test, insulation resistance. 2.3 All diagnostic test results are interpreted and analysed for compliance with standard. may include but is not limited to results that are outside of enterprise, client or international standards and where corrective action is required. Interpretation of results may include recommendations for servicing action.

4 Page 4 of 5 Element 3 Carry out servicing. 3.1 All required servicing is carried out consistent with guidelines and procedures. may include but is not limited to the following activities cleaning ceramic or cast resin bushings, oil replace or top up, terminal connections checked, seismic constraints are secure, special care of hydrophobic surfaces. 3.2 All equipment is reinstated on the instrument transformers. may include but is not limited to all restored equipment is fitted correctly in the proper order and secured ready for service, connections tight and electrically correct, oil levels or gas pressure are to required level. Element 4 Record routine inspection and servicing. 4.1 The as left conditions are recorded in the plant history or defect history. may include but is not limited to analysis and reporting of any defects, correct completion of the plant history including items replaced. 4.2 The equipment condition status is recorded in accordance with client requirements. may include but is not limited to cyclo recorder, number of trial operations noted, pressures and auxiliary service quantified, replacement spares fitted. Element 5 Return equipment to service. 5.1 Work party is withdrawn and warned the equipment is no longer safe to work on. includes notification to the work party to regard the equipment as live when they have signed off.

5 Page 5 of All tools and recipient-applied safety measures are removed in accordance with client requirements. includes all access devices, for example, work platforms, scaffold, cherry pickers. 5.3 All equipment worked on is inspected and set for return to service. includes confirming all equipment and the work party are clear, all operational equipment which has been worked on is now set ready for service. 5.4 Return of access permit, or approved equivalent, is confirmed. includes confirming all members of the work party have signed off. The equipment is returned to service without incident. Please note Providers must be accredited by NZQA, or an inter-institutional body with delegated authority for quality assurance, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment. Industry Training Organisations must be accredited by NZQA before they can register credits from assessment against unit standards. Accredited providers and Industry Training Organisations assessing against unit standards must engage with the moderation system that applies to those standards. Accreditation requirements and an outline of the moderation system that applies to this standard are outlined in the Accreditation and Moderation Action Plan (AMAP). The AMAP also includes useful information about special requirements for organisations wishing to develop education and training programmes, such as minimum qualifications for tutors and assessors, and special resource requirements. Comments on this unit standard Please contact the Electricity Supply Industry Training Organisation info@esito.org.nz if you wish to suggest changes to the content of this unit standard.