Page 1 of 4
Title / Demonstrate knowledge of electric switchboard testing
Level / 4 / Credits / 3
Purpose / This unit standard is intended for the training and assessment of people engaged in the manufacture of electric switchboards and covers electric switchboard testing theory.
People credited with this unit standard are able to:
–describe switchboard test equipment;
–demonstrate knowledge of switchboard inspection and testing methods;
–demonstrate knowledge of anticipated results of switchboard tests; and
–explain the application of thermal imaging to switchboard testing.
Classification / Electrical Engineering > Electric Switchboards
Available grade / Achieved
Explanatory notes
1This unit standard has been developed for learning and assessment off-job.
2References
Electricity Act 1992;
Electricity (Safety) Regulations 2010;
Health and Safety in Employment Act 1992 and associated regulations;
Accident Compensation Act 2001;
AS/NZS 3000:2007,Electrical installations (known as the Australian/New Zealand Wiring Rules), including Amendment 1;
AS/NZS 3439.4:2009, Low-voltage switchgear and controlgear assemblies – Particular requirements for assemblies for construction sites (ACS);
New Zealand Electrical Codes of Practice (NZECP), ISSN 0114-0663 (available from the Ministry of Business, Innovation and Employment);
and all subsequent amendments and replacements.
3Definitions
CT – current transformers.
HV – high voltage.
Industry practice – practice used and recommended by organisations involved in the electrotechnology industry.
Switchboard – low-voltage switchgear and controlgear assemblies, the rated voltage of which does not exceed 1000 V a.c. at frequencies not exceeding 1000 Hz, or 1500 V d.c.
VT – voltage transformers.
4Range
All knowledge demonstrated is to be conducted in accordance with applicable specifications, documented enterprise, legislative and/or regulatory requirements, and local bylaws.
Outcomes and evidence requirements
Outcome 1
Describe switchboard test equipment.
Rangetest equipment includes – insulation tester, HV tester, current injection test set, ductor set, CT, polarity test set.
Evidence of five instruments is required.
Evidence requirements
1.1The purpose of each piece of equipment is described.
1.2The method of use of each piece of equipment is explained in relation to specific test requirements.
1.3Calibration needs and safety precautions appropriate to the use of each piece of equipment is described.
Outcome 2
Demonstrate knowledge of switchboard inspection and testing methods.
Evidence requirements
2.1A typical sequence of inspections and tests, which provides for efficiency and safety, is described.
Rangeinspections – layout, busbars;
tests – CT, VT, wiring, insulation, potential, functional.
2.2CT tests, polarity testing, and current injection testing are described in terms of procedure and instruments used.
2.3The test voltages to be used for common nominal switchboard voltages are stated.
2.4One method of systematically testing the operating voltages of all circuits in the switchboard is explained in accordance with industry practice.
2.5One method of calibrating and testing circuit breakers is described in accordance with industry practice.
2.6The safe working clearances for high-voltage testing and operational testing are stated in accordance with industry practice.
Outcome 3
Demonstrate knowledge of anticipated results of switchboard tests.
Evidence requirements
3.1Typical tolerances for test results are stated.
3.2Flashover and/or puncture occurring during insulation and HV tests are explained.
3.3Reasons for acceptable pass/fail criteria for insulation tests carried out at the test voltages defined in AS/NZS 3439.1:2002 Table 10 are stated.
3.4Primary VT ratio and its relevance to test results are described.
Outcome 4
Explain the application of thermal imaging to switchboard testing.
Evidence requirements
4.1The term thermal imaging is explained with reference to the operation and use of thermal imaging equipment.
4.2Thermal imaging is explained in terms of how it detects hot spots on the switchboard.
4.3Types of fault that may be detected with thermal imaging technology is explained.
Replacement information / This unit standard was replaced by unit standard 29762.This unit standard is expiring. Assessment against the standard must take place by the last date for assessment set out below.
Status information and last date for assessment for superseded versions
Process / Version / Date / Last Date for AssessmentRegistration / 1 / 31 August 1998 / 31 December 2013
Revision / 2 / 12 March 2002 / 31 December 2013
Review / 3 / 20 March 2008 / 31 December 2021
Rollover and Revision / 4 / 15 March 2012 / 31 December 2021
Revision / 5 / 15 January 2014 / 31 December 2021
Review / 6 / 17 November 2016 / 31 December 2021
Consent and Moderation Requirements (CMR) reference / 0003
This CMR can be accessed at
Please note
Providers must be granted consent to assess against standards (accredited) by NZQA, before they can report credits from assessment against unit standards or deliver courses of study leading to that assessment.
Industry Training Organisations must be granted consent to assess against standards by NZQA before they can register credits from assessment against unit standards.
Providers and Industry Training Organisations, which have been granted consent and which are assessing against unit standards must engage with the moderation system that applies to those standards.
Requirements for consent to assess and an outline of the moderation system that applies to this standard are outlined in the Consent and Moderation Requirements (CMR). The CMR 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.
The Skills OrganisationSSB Code 100401 / New Zealand Qualifications Authority 2018 / / New Zealand Qualifications Aut