NZQA registered unit standard
26019 version 3
Page 1 of 7
Title
Demonstrate knowledge of introductory concepts in power system
protection
Level
4
Credits
10
Purpose
People credited with this unit standard are able to: demonstrate
a basic knowledge and understanding of the power system in
operation within New Zealand; demonstrate knowledge and
understanding of basic protection concepts; demonstrate
knowledge and understanding of the fault types identifiable in
power system protection systems; draw a single line diagram
showing circuit characteristics; demonstrate knowledge and
understanding of basic low voltage (LV) protective devices;
demonstrate knowledge and understanding of the types, ratios,
and classes for CTs, capacitive voltage transformers (CVTs)
and VTs, and the calculation of secondary currents from
theoretical full load currents for CTs and their ratios;
demonstrate knowledge of the danger of open circuit operation
of a CT and precautions and safe working practices; and
demonstrate knowledge of safety and safe working practices
when operating in a HV environment.
Classification
Electricity Supply > Electricity Supply - Power System
Maintenance
Available grade
Achieved
Entry information
Critical health and
safety prerequisites
Unit 14287, Use and maintain test instruments used within the
high voltage electrical industry, or demonstrate equivalent
knowledge and skills.
Explanatory notes
1
This unit standard is intended for off-job assessment. The range statements across
the unit standard can be applied according to industry-specific equipment,
procedures, and processes.
2
Protection systems may include those associated with prime movers, generators,
transformers, bus work and distribution networks including: fault detection systems,
shutdown and alarm initiation systems, electrical protective relays, voltage and
current transformers, field devices, transducers, programmable logic controllers,
computers, and alarm annunciation systems.
Electricity Supply Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
26019 version 3
Page 2 of 7
3
Sources of information include but are not limited to the International Electrotechnical
Commission (IEC), the Institution of Engineering and Technology (IET), the American
National Standards Institute (ANSI), and the Deutsches Institut für Normung e. V. (DIN).
4
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 regulations and codes of practice recognised under that statute; the
Health and Safety in Employment Act 1992; and the Resource Management Act
1991. Electricity supply industry codes of practice and documented industry
procedures include the Safety Manual – Electricity Industry (SM-EI) (Wellington:
Electricity Engineers’ Association, 2010). A full list of current legislation and industry
codes of practice is available from the Electricity Supply Industry Training
Organisation, PO Box 1245, Hamilton 3240.
5
The outcomes of this unit standard are equivalent to the learning outcomes of the
New Zealand Board of Engineering Diplomas (NZBED) course component DE5413
Power Protection Systems 1 Level 5. If a candidate has completed the NZBED
course component related to this standard then they can apply to the ITO for
Recognised Prior Learning (RPL). Further information about this process may be
obtained from the Electricity Supply Industry Training Organisation, PO Box 1245,
Hamilton 3240.
Outcomes and evidence requirements
Outcome 1
Demonstrate a basic knowledge and understanding of the power system in operation
within New Zealand.
Evidence requirements
1.1
The importance of the power system to New Zealand is described.
Range
1.2
The structure of the National Grid and the distribution networks through to
consumer is described.
Range
1.3
generation, High Voltage Direct Current (HVDC) link, transmission
voltages, major exit points.
The types of generation, load patterns, and basic operational constraints are
described.
Range
1.4
current loads, projected demand.
introduction to HV transmission, HV substations, distribution
substations.
The role of components in the power system is described.
Range
circuit breakers, switch gear, transformers, voltage transformers
(VT), current transformers (CT), protection equipment.
Electricity Supply Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
1.5
26019 version 3
Page 3 of 7
The ability to read and understand single line diagrams is demonstrated.
Outcome 2
Demonstrate knowledge and understanding of basic protection concepts.
Evidence requirements
2.1
The physiological effects of electric shock on humans are described.
2.2
The need for protection equipment is explained.
Range
2.3
Basic circuit break fundamentals are identified.
Range
2.4
time/current characteristics, short circuit and overload, prospective
short circuit currents (PSCC).
bulk oil, air blast, vacuum, sulphar hexafluoride (SF6), kilovolt
amps (kV) ratings, current interruptions, containment and levels of
faults, different types of faults, arc quenching mechanisms.
Point-on-Wave circuit breakers are described.
Outcome 3
Demonstrate knowledge and understanding of the fault types identifiable in power system
protection systems.
Range
includes but is not limited to – transient faults, high resistance faults, incidence
of faults on power system equipment.
Evidence requirements
3.1
The origins of faults are identified and named.
3.2
The types of earthing systems are identified and the phase to earth fault is
described.
3.3
Proposals are provided for the protection against earth faults.
3.4
Detection and clearance of faults are described.
3.5
The effects of these types of faults on the system, system stability, overloads
and the effects of loss of supply are described.
3.6
The short circuit current of a power transformer from its capacity and
impedance is calculated.
Electricity Supply Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
26019 version 3
Page 4 of 7
Outcome 4
Draw a single line diagram showing circuit characteristics.
Evidence requirements
4.1
A simple power system single line diagram is developed.
4.2
A short circuit megavolt amperes (MVA) is calculated on the diagram.
4.3
Fault currents are calculated.
4.4
Equipment MVA fault ratings are identified.
Outcome 5
Demonstrate knowledge and understanding of basic low voltage (LV) protective devices.
Range
up to 11kV.
Evidence requirements
5.1
Fuse characteristics, ratings, and selection for overload and prospective fault
situations are described.
5.2
Circuit breaker ratings are identified.
5.3
Residual current device (RCD) operations, ratings, and testings are described.
5.4
Ring main unit (RMU) circuits are described.
Outcome 6
Demonstrate knowledge and understanding of the types, ratios, and classes for CTs,
capacitive voltage transformers (CVTs) and VTs, and the calculation of secondary currents
from theoretical full load currents for CTs and their ratios.
Evidence requirements
6.1
The different ratios and classes of CTs and VTs are described in detail.
6.2
Three examples are identified of how CT specifications, primary currents, and
circuit burden are used to calculate the secondary currents for a CT and to
determine if the results are permissible values.
Range
includes but is not limited to – magnetisation curves, knee point
saturation, protection versus metering types, ratios.
Electricity Supply Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
6.3
The examples given describe discrimination in detail and explain how it was
achieved in each case.
Range
6.4
includes but is not limited to – supply networks, motors,
transformers, generators.
The role and function of instrument transformers are described.
Range
6.5
26019 version 3
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different classes, accuracy classifications, acceptance testing,
earthing of secondaries.
Connection diagrams are drawn.
Range
CT, VT, CVT.
Outcome 7
Demonstrate knowledge of the danger of open circuit operation of a CT and precautions
and safe working practices.
Evidence requirements
7.1
Theoretical explanations for not operating a CT in an open circuit condition are
stated.
7.2
Safety issues about operating open circuit CTs are described.
7.3
Precautions and safe working practices when engaged in testing power system
protection schemes are identified and described.
Range
includes but is not limited to – step and touch voltages, safe
working distances, current loops, instrument maintenance,
applicable legislation, industry codes of practice.
Outcome 8
Demonstrate knowledge of safety and safe working practices when operating in a HV
environment.
Range
up to 400kV.
Evidence requirements
8.1
Precautions and safe working practices when engaged in electrical testing of
equipment and protection schemes are identified and described.
Range
the effect on humans of electric shock and the dangers of
electrical power arcs (relevant recent electrical industry accidents
with analysis of their cause may be included), maintenance and
repair work procedures, troubleshooting, testing on energised
electrical circuits, components, or systems.
Electricity Supply Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
8.2
Managing potential hazards in the workplace is discussed.
Range
8.3
use of appropriate personal protective equipment (PPE) for the
work environment, maintaining PPE in a safe and reliable
condition, inspection of PPE prior to use, procedures for inspection
following any incident, basic instrument and hand tool
maintenance and care.
Work authorisations are described.
Range
8.4
26019 version 3
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levels of authorisations, how to request work authorisations,
responsibilities, examples of documents in current use, typical
commissioning programs.
Electrical work hazards in the workplace are identified.
Range
defined work areas, lock and tag procedures, structure diagrams
(up to 400kV) including but not limited to proximity to higher
voltages (400kV), exposure to higher fault levels, step and touch
voltages, electrostatic charges, emergency response systems and
procedures to follow to ensure safety in the event of an incident.
Planned review date
31 December 2013
Status information and last date for assessment for superseded versions
Process
Version Date
Last Date for Assessment
Registration
1
20 November 2009
December 2012
Revision
2
22 October 2010
N/A
Revision
3
21 July 2011
N/A
Consent and Moderation Requirements (CMR) reference
0120
This CMR can be accessed at http://www.nzqa.govt.nz/framework/search/index.do.
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.
Electricity Supply Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016
NZQA registered unit standard
26019 version 3
Page 7 of 7
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 (CMRs). 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 Electricity Supply Industry Training Organisation info@esito.org.nz if
you wish to suggest changes to the content of this unit standard.
Electricity Supply Industry Training Organisation
SSB Code 101813
 New Zealand Qualifications Authority 2016