NZQA registered unit standard
23896 version 3
Page 1 of 4
Title
Demonstrate knowledge of electrical circuit protection for distribution
networks
Level
4
Purpose
Credits
4
This unit standard is intended for distribution line mechanics
and substation maintenance in the electricity supply industry.
People credited with this unit standard are able to demonstrate
knowledge of: electrical circuit protection terms and principles
for electricity supply networks; and circuit protection devices
used for electricity supply networks; and of practical electrical
faults causing operation of protective devices.
Classification
Electricity Supply > Electricity Supply - Distribution Networks
Available grade
Achieved
Explanatory notes
1
This unit standard is intended for assessment off-job. The range statements across
the unit standard can be applied according to industry specific equipment,
procedures, and processes.
2
Safety of personnel and plant must be a priority throughout the assessment. If the
safety requirements are not met the assessment must stop and the candidate will be
assessed as not yet competent.
3
Performance and work practices in relation to the outcomes and evidence
requirements must comply with all current legislation, especially the Electricity Act
1992 and any subsequent amendments, and any regulations, codes of practice
recognised under that statute, Health and Safety in Employment Act 1992, the
Resource Management Act 1991, and their subsequent amendments, electricity
supply industry codes of practice and documented enterprise procedures. These
include the latest version of, Safety Manual – Electricity Industry (SM-EI) (2004)
Wellington: Electricity Engineers’ Association.
A full list of current legislation and industry codes is available from:
Infrastructure Industry Training Organisation
PO Box 1245
HAMILTON.
4
The phrase in accordance with industry requirements is implicit in all outcomes and
evidence requirements in this unit standard.
Infrastructure Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
23896 version 3
Page 2 of 4
5
Definitions
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 in which assessment is carried out.
Asset owner refers to the owner of an electricity supply network that takes its point of
supply from Transpower NZ, and delivers electricity to industrial, commercial and
residential customers.
Asset owner standards are the approved documented work site methods for carrying
out work on an electrical supply network to the standard required by the asset owner.
6
This unit standard is intended for use in the assessment of line mechanics and
substation maintenance, and all terminology should be related to that sector of the
industry.
Outcomes and evidence requirements
Outcome 1
Demonstrate knowledge of electrical circuit protection principles and terminology for
electricity supply networks.
Evidence requirements
1.1
The need for circuit protection in electricity supply networks is explained.
Range
1.2
Circuit protection terms are explained.
Range
1.3
cable ampacity, conductor insulation, circuit isolation, overloads
and short circuits.
may include but is not limited to – current rating, voltage rating,
utilisation category, interrupting capacity (breaking capacity),
fusing and tripping factor, excess current protection (coarse and
close), prospective short circuit current (pscc);
evidence of four is required.
Relationship between current rating, interrupting capacity and utilisation
category for a protection device is stated and explained.
Outcome 2
Demonstrate knowledge of circuit protection devices used for electricity supply networks.
Evidence requirements
2.1
Protection devices used in an electricity supply network are described with the
aid of drawings showing construction and operating principles in simple terms.
Range
devices (high voltage HV and low voltage LV) – rewirable fuses,
open fuses, liquid fuses, high rupturing capacity (HRC) fuses,
fusible links, HV expulsion fuses (EDO), circuit breakers (oil filled,
Infrastructure Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
23896 version 3
Page 3 of 4
gas, vacuum), protection relays (voltage, current, differential,
phase-failure, directional), auto-reclosers;
evidence of three is required.
2.2
Fuse link types used for protection in electricity supply networks are identified
physically and by product references.
Range
at least three different types.
Outcome 3
Demonstrate knowledge of practical electrical faults causing operation of protective
devices.
Evidence requirements
3.1
Effects of electrical faults are described in terms of the danger to people,
property and Electricity Network components.
may include but is not limited to – insulation breakdown, leakage
current, over current, short circuit, physical damage (bird strike,
fallen tree, possums, accidents, lightning strikes and switching
surges) damage to cables, conductors, equipment due to over
heating, or mechanical forces, non-operation of protection
equipment in fault and accidents;
evidence of three is required.
Range
3.2
Importance of time in relation to the isolation of faults is explained in terms of
industry requirements.
3.3
The purpose, function, and location where auto-recloser and sectionalisers are
used in the Electricity network are described.
Planned review date
31 December 2019
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
25 October 2007
31 December 2016
Review
2
20 March 2014
31 December 2016
Rollover and
Revision
3
18 September 2014
N/A
Consent and Moderation Requirements (CMR) reference
0120
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
Infrastructure Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
23896 version 3
Page 4 of 4
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.
Comments on this unit standard
Please contact the Infrastructure Industry Training Organisation
qualification@infrastructureito.org.nz if you wish to suggest changes to the content of this
unit standard.
Infrastructure Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016