SIST EN 62006:2011

SLOVENSKI STANDARD
01-april-2011
Vodni stroji - Prevzemni preskusi majhnih hidroelektrarn (IEC 62006:2010)
Hydraulic machines - Acceptance tests of small hydroelectric installations (IEC
62006:2010)
Hydraulische Maschinen - Abnahmemessungen an Kleinwasserkraft-Anlagen (IEC
62006:2010)
Machines hydrauliques - Essais de réception des petits aménagements hydroélectriques
(CEI 62006:2010)
Ta slovenski standard je istoveten z: EN 62006:2011
ICS:
27.140 Vodna energija Hydraulic energy engineering
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 62006
NORME EUROPÉENNE
February 2011
EUROPÄISCHE NORM
ICS 27.140
English version
Hydraulic machines -
Acceptance tests of small hydroelectric installations
(IEC 62006:2010)
Machines hydrauliques -  Hydraulische Maschinen -
Essais de réception des petits Abnahmemessungen an Kleinwasserkraft-
aménagements hydroélectriques Anlagen
(CEI 62006:2010) (IEC 62006:2010)

This European Standard was approved by CENELEC on 2011-01-02. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2011 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62006:2011 E
Foreword
The text of document 4/254/FDIS, future edition 1 of IEC 62006, prepared by IEC TC 4, Hydraulic
turbines, was submitted to the IEC-CENELEC parallel vote and was approved by CENELEC as
EN 62006 on 2011-01-02.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN and CENELEC shall not be held responsible for identifying any or all such patent
rights.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
(dop) 2011-10-02
national standard or by endorsement
– latest date by which the national standards conflicting
(dow) 2014-01-02
with the EN have to be withdrawn
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 62006:2010 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60994 NOTE  Harmonized as EN 60994.
IEC 61116 NOTE  Harmonized as EN 61116.
IEC 61260 NOTE  Harmonized as EN 61260.
ISO 4373 NOTE  Harmonized as EN ISO 4373.
ISO 5167 series NOTE  Harmonized in EN ISO 5167 series (not modified)
__________
- 3 - EN 62006:2011
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

IEC 60041 1991 Field acceptance tests to determine the EN 60041 1994
hydraulic performance of hydraulic turbines,
storage pumps and pump-turbines

IEC 60193 - Hydraulic turbines, storage pumps and EN 60193 -
pump-turbines - Model acceptance tests

IEC 60308 - Hydraulic turbines - Testing of control EN 60308 -
systems
IEC 60609 Series Hydraulic turbines, storage pumps and EN 60609 Series
pump-turbines - Cavitation pitting evaluation

IEC 60651 - Sound level meters EN 60651 -

IEC 61362 - Guide to specification of hydraulic turbine EN 61362 -
control systems
ISO 1680 - Acoustics - Test code for the measurement EN ISO 1680 -
of airborne noise emitted by rotating electrical
machines
ISO 1940-1 2003 Mechanical vibration - Balance quality - -
requirements for rotors in a constant (rigid)
state -
Part 1: Specification and verification of
balance tolerances
ISO 3746 - Acoustics - Determination of sound power EN ISO 3746 -
levels of noise sources using sound pressure -
Survey method using an enveloping
measurement surface over a reflecting plane

ISO 4412 Series Hydraulic fluid power - Test code for - -
determination of airborne noise levels

ISO 5168 - Measurement of fluid flow - Estimation of - -
uncertainly of a flow-rate measurement

ISO 7919-5 - Mechanical vibration - Evaluation of machine - -
vibration by measurements on rotating shafts -
Part 5: Machine sets in hydraulic power
generating and pumping plants
ISO 10816-3 - Mechanical vibration - Evaluation of machine - -
vibration by measurements on non-rotating
parts -
Part 3: Industrial machines with nominal
power above 15 kW and nominal speeds
between 120 r/min and 15 000 r/min when
measured in situ
Publication Year Title EN/HD Year

ANSI/IEEE 810 - Hydraulic Turbine and Generator Integrally - -
Forged Shaft Couplings and Shaft Runout
Tolerances
IEC 62006 ®
Edition 1.0 2010-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Hydraulic machines – Acceptance tests of small hydroelectric installations

Machines hydrauliques – Essais de réception des petits aménagements
hydroélectriques
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
XE
CODE PRIX
ICS 27.140 ISBN 978-2-88912-228-8
– 2 – 62006 © IEC:2010
CONTENTS
FOREWORD.7
1 Scope.9
2 Normative references .9
3 Terms, definitions and schematic layout .10
3.1 Terms and definitions .10
3.2 Schematic layout of a hydroelectric installation .10
4 Nature and extent of guarantees.11
4.1 Grouping of classes A, B, C.11
4.1.1 General .11
4.1.2 Contract conditions.13
4.2 Scope of performance guarantee.13
4.2.1 General .13
4.2.2 Class A: Maximum power output.13
4.2.3 Class B: Index test .13
4.2.4 Class C: Turbine efficiency .13
4.2.5 Interpretation of losses .13
4.3 Scope of tests .14
4.3.1 Safety tests .14
4.3.2 Trial run and reliability tests.14
4.3.3 Performance test .14
4.4 Aptitude.15
4.5 Warranty .15
5 Safety tests (commissioning) .16
5.1 Pre-start tests .16
5.2 Closing devices .16
5.2.1 General .16
5.2.2 Intake gate or valve .17
5.2.3 Turbine inlet valve .17
5.2.4 Guide vanes (Francis and Kaplan turbines) .17
5.2.5 Needle valve and deflector (Pelton and Turgo turbines).18
5.3 First run operation and control.19
5.4 Bearing run at rated speed .19
5.5 Emergency shutdown (no load) .20
5.6 Electrical protection.20
5.7 Overspeed test.21
5.8 Runaway test .21
5.9 Overpressure, emergency trip and load rejection tests .22
5.9.1 General conditions .22
5.9.2 Testing the guide vanes or needle valves .23
5.9.3 Testing the turbine inlet valve.23
5.9.4 Testing the pressure relief valve.23
5.9.5 Pressure rise .23
5.10 Measured quantities .25
5.10.1 Pressure.25
5.10.2 Speed.25
5.10.3 Control components.25

62006 © IEC:2010 – 3 –
6 Trial operating and reliability tests (commissioning).25
6.1 General .25
6.2 Temperature stability of rotating parts .25
6.2.1 General .25
6.2.2 Temperature guarantees .26
6.3 Speed controller system .26
6.3.1 General .26
6.3.2 Unit operating without regulation .26
6.3.3 Unit operating with a speed governor.27
6.3.4 Unit operating with a voltage governor.28
6.3.5 Unit operating with a controller .28
6.3.6 Measurements when testing the control system .28
6.4 Control of cam correlation .29
7 Performance guarantees and tests .29
7.1 General .29
7.2 Maximum generator (transformer) power output as a function of net head .30
7.2.1 Guarantee .30
7.2.2 Instrumentation.30
7.3 Index test .30
7.3.1 General .30
7.3.2 Index discharge measurement .31
7.3.3 Shape control .31
7.3.4 Index plant efficiency.32
7.3.5 Optimizing cam correlation .33
7.4 Turbine efficiency.33
7.4.1 Efficiency test by absolute discharge measurement.33
7.4.2 Efficiency test by thermodynamic method .34
7.5 Correcting the efficiency using the model curve.34
8 Computation of results and comparison to the guarantee.36
8.1 General .36
8.1.1 Site data.36
8.1.2 Measured values (readings) .36
8.1.3 Scale effect due to water temperature .37
8.1.4 Shifting of the plant characteristic.37
8.2 Power output .37
8.2.1 Plant power output measurement .37
8.2.2 Generator power output measurement.38
8.2.3 Turbine power output measurement.38
8.3 Relative turbine efficiency (index test) .38
8.3.1 General .38
8.3.2 Relative discharge.38
8.3.3 Guarantee of the shape of the plant characteristics .39
8.3.4 Relative index plant efficiency .40
8.4 Absolute turbine efficiency .40
8.4.1 General .40
8.4.2 Absolute discharge .40
8.4.3 Guarantee of the plant efficiency and comparison to the results .40
9 Error analysis .40

– 4 – 62006 © IEC:2010
9.1 General .40
9.2 Estimation of systematic (bias) uncertainties .41
9.2.1 General .41
9.2.2 Typical systematic uncertainties .41
9.2.3 Systematic uncertainty for turbines used to indicate discharge .42
9.3 Estimation of random (precision) uncertainties .42
9.3.1 Measurement at a single operation point .42
9.3.2 Measurement over a range of operating condition .44
9.4 Evaluation of the uncertainties .45
9.4.1 General .45
9.4.2 Head .45
9.4.3 Power output .47
9.4.4 Index test measurement .49
9.4.5 Efficiency test by absolute discharge measurement.51
9.4.6 Efficiency test by the thermodynamic method .51
10 Other guarantees .51
10.1 Cavitation.51
10.1.1 General .51
10.1.2 Measurement methods .52
10.1.3 Comparison with specified guarantees.52
10.2 Noise .53
10.2.1 General .53
10.2.2 Measurement methods .53
10.2.3 Comparison with specified guarantees.54
10.3 Vibration.54
10.3.1 General .54
10.3.2 Measurements and measurement methods.54
10.3.3 Comparison with specified guarantees.55
Annex A (normative) Terms, definitions, symbols and units.56
Annex B (normative) Head definition.64
Annex C (normative) Method of speed measurements .77
Annex D (normative) Power output measurement .78
Annex E (normative) Methods of discharge measurement.82
Annex F (informative) Plant condition .95
Annex G (informative) Commissioning .97
Annex H (informative) Performance test efficiency calculation .99
Annex I (informative) Cam correlation test . 106
Bibliography.109

Figure 1 – Schematic layout of a hydroelectric installation (water to wire system) .11
Figure 2 – Warranty period .16
Figure 3 – Vanes and blades servomotors force measurements (Kaplan on line) .17
Figure 4 – Evaluation of the guide vane (GV) closing characteristic .18
Figure 5 – Needle servomotor force .18
Figure 6 – Automatic start – Synchronization – No load test (Kaplan turbine).19
Figure 7 – Emergency shutdown from no load test (Kaplan turbine) .20

62006 © IEC:2010 – 5 –
Figure 8 – Runaway test (Kaplan turbine) .21
Figure 9 – Emergency shutdown due to an electrical fault.22
Figure 10 – Emergency shutdown due to a mechanical fault .23
Figure 11 – Emergency shutdown due to the governor failure .24
Figure 12 – Evaluation of the maximum overpressure .24
Figure 13 – Temperature stability, recording at no load up to stable conditions.26
Figure 14 – Speed governor check at no load .27
Figure 15 – Maximum power output: procedure to compare measured power output at
actual net head to the guarantee.30
Figure 16 – Comparison of the shape of the turbine characteristic to the guarantee.32
Figure 17 – Example of an optimized switch band for 1 and 2 turbine operation.33
Figure 18 – Efficiency test: procedure to compare guaranteed turbine efficiency to the
prototype measurement results, including the overall uncertainties .34
Figure 19 – Hill chart – Showing head loss examples with one and two units in
operation using the same penstock.35
Figure 20 – Shifting of the performance curves .37
Figure 21 – Variation of factor k and exponent x on turbine index efficiency.39
Figure 22 – Random uncertainties of a single operation point, example for penstock
pressure variation and fluctuation .43
Figure 23 – Detection of outlier errors: example to find out offset and reading errors
by plotting in linear and logarithmic form with the same data.44
Figure 24 – Example of scattered points with function of second order .44
Figure 25 – Scattered points smoothed by individual fitting on adjacent sections .45
Figure 26 – Overall uncertainty of head for free water level for low head turbines .46
Figure 27 – Overall uncertainty of head in a closed conduit .47
Figure 28 – Estimated overall uncertainties of the discharge by index measurement
versus full scale differential pressure .50
Figure 29 – Operation range and cavitation limits .52
Figure A.1 – Transient pressure fluctuation at the turbine high pressure reference
section, when a specified load is suddenly rejected .61
Figure A.2 – Transient pressure fluctuation at the turbine high pressure reference
section, when a specified load is suddenly accepted.62
Figure B.1 – High pressure reference and measuring sections.65
Figure B.2 – Measuring section at tail water.66
Figure B.3 – Measuring section at draft tube.66
Figure B.4 – Definition of measuring sections .67
Figure B.5 – Kaplan turbine with horizontal shaft .68
Figure B.6 – Kaplan turbine with vertical shaft .68
Figure B.7 – Francis open flume turbine with vertical shaft .69
Figure B.8 – Francis turbine with horizontal shaft.69
Figure B.9 – Francis turbine with vertical shaft, with stagnation probe .70
Figure B.10 – Francis turbine with horizontal shaft with pressure on suction side.70
Figure B.11 – Pelton turbine with horizontal shaft .71
Figure B.12 – Pelton turbine with vertical shaft .71
Figure B.13 – Turgo turbine with horizontal shaft .72
Figure B.14 – Turgo turbine with vertical shaft .72

– 6 – 62006 © IEC:2010
Figure B.15 – Crossflow turbine with horizontal shaft, with draft tube.73
Figure B.16 – Crossflow turbine with horizontal shaft, without draft tube .73
Figure B.17 – Specifications for static pressure taps.74
Figure B.18 – Example: discharge versus guide vane opening.76
Figure C.1 – Overspeed and runaway .77
Figure D.1 – Typical losses of a synchronous generator .79
Figure D.2 – Asynchronous generator: typical power factor and slip factor.80
Figure D.3 – Power measurement using the two wattmeter method.80
Figure D.4 – Power measurement using the three wattmeter method .81
Figure E.1 – Typical arrangements of acoustic transducers .84
Figure E.2 – Arrangement for pressure time method .85
Figure E.3 – Example of pressure-time diagram for a uniform conduit.86
Figure E.4 – Example of pressure-time diagram for a non-uniform conduit.86
Figure E.5 – Example of pressure-time diagram for a combination of uniform and non-
uniform conduits between several sections .87
Figure E.6 – Location of taps for differential pressure method of discharge
measurement.93
Figure E.7 – Location of taps for differential pressure measurement of discharge in a
bulb turbine .93
Figure E.8 – Location of taps for Winter-Kennedy method of discharge measurement
through a turbine equipped with a steel spiral case.94
Figure H.1 – Comparison of measured index efficiency with the guaranteed values .105
Figure I.1 – Index measurement to optimize the efficiency .107
Figure I.2 – Two dimensional cam correlation .108

Table 1 – Scope of classes A, B, and C .12
Table 2 – Maximum runaway speeds (n ) expressed as a percentage of rated speed.21
run
Table 3 – Performance test parameters .29
Table 4 – Index discharge measurement methods .31
Table 5 – Site data .36
Table 6 – Systematic uncertainties at full load .41
Table 7 – Systematic uncertainties of discharge versus turbine opening .42
Table 8 – Overall uncertainties of the shape of turbine characteristics with respect to
the guaranteed efficiency.49
Table 9 – Data used in Figure 28 .51
Table 10 – Limits for cavitation damage.53
Table A.1 – Density of water .62
Table E.1 – Selection of flow measurement method .82
Table E.2 – Evaluation of the penstock factor with estimation of the systematic
uncertainty.91
Table H.1 – Plant index efficiency guarantee .99
Table H.2 – Transformer data .100
Table H.3 – Data measurements (not all tests included) .101
Table H.4 – Calculation of results .102

62006 © IEC:2010 – 7 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HYDRAULIC MACHINES – ACCEPTANCE TESTS
OF SMALL HYDROELECTRIC INSTALLATIONS

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
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agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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6) All users should ensure that they have the latest edition of this publication.
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expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 62006 has been prepared by IEC technical committee 4: Hydraulic
turbines.
The text of this standard is based on the following documents:
FDIS Report on voting
4/254/FDIS 4/257/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

– 8 – 62006 © IEC:2010
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
62006 © IEC:2010 – 9 –
HYDRAULIC MACHINES – ACCEPTANCE TESTS
OF SMALL HYDROELECTRIC INSTALLATIONS

1 Scope
This International Standard defines the test, the measuring methods and the contractual
guarantee conditions for field acceptance tests of the generating machinery in small
hydroelectric power installations. It applies to installations containing impulse or reaction
turbines with unit power up to about 15 MW and reference diameter of about 3 m. The driven
generator can be of synchronous or asynchronous type.
This International Standard contains information about most of the tests required for
acceptance of the hydraulic turbine such as safety approval tests, trial operating and reliability
tests, as well for verification of cavitation, noise and vibration conditions, if required.
This standard represents the typical methods used on smaller hydroelectric installations, and
is divided into three classes as follows (see Table 1 for more detail):
Class A Normal test program (panel measurement) Default
To determine the maximum power output of the
installation.
Class B Extended test program Recommended
To determine the performance characteristics of the
installation.
Class C Optional
Comprehensive test program
To determine the absolute efficiency of the installation.
NOTE All classes contain safety tests, trial operating tests, and reliability tests.
This standard gives all necessary references for the contract in order to execute the test,
evaluate, calculate and compare the result to the guarantee for all the classes A, B and C.
The manufacturer or consulting engineer is responsible for ensuring that standardized
connections are installed for performing these tests. This standard does not cover the
structural details of a hydroelectric installation or its component parts.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60041:1991, Field acceptance tests to determine the hydraulic performance of hydraulic
turbines, storage pumps and pump turbines
IEC 60193, Hydraulic turbines, storage pumps and pump-turbines – Model acceptance tests
IEC 60308, Hydraulic turbines – Testing of control systems
IEC 60609 (all parts), Hydraulic turbines, storage pumps and pump-turbines – Cavitation
pitting evaluation
IEC 60651, Specification for sound level meters

– 10 – 62006 © IEC:2010
IEC 61362, Guide to specification of hydraulic turbine control systems
ISO 1680 Acoustics – Test code for the measurement of airborne noise emitted by rotating
electrical machinery
ISO 1940-1:2003, Mechanical vibration – Balance quality requirements for rotors in a
constant (rigid) state – Part 1: Specification and verification of balance tolerances
ISO 3746, Acoustics – Determination of sound power levels of noise sources using sound
pressure – Survey method using an enveloping measurement surface over a reflecting plane
ISO 4412 (all parts), Hydraulic fluid power – Test code for determination of airborne noise
levels
ISO 5168, Measurement of fluid flow – Procedures for the evaluation of uncertainties
ISO 7919-5, Mechanical vibration – Evaluation of machine vibration by measurements on
rotating shafts – Part 5: Machine sets in hydraulic power generating and pumping plants
ISO 10816-3, Mechanical vibration – Evaluation of machine vibration by measurements on
non-rotating parts – Part 3: Industrial machines with nominal power above 15 kW and nominal
speeds between 120 r/min and 15 000 r/min when measured in situ
ANSI/IEEE 810, Hydraulic Turbine and Generator Integrally Forged Shaft Couplings and
Shaft Runout Tolerances
3 Terms, definitions and schematic layout
3.1 Terms and definitions
A complete list of terms and definitions is given in Annex A.
3.2 Schematic layout of a hydroelectric installation
In general, there are three connected hydraulic regimes in a hydroelectric installation as
shown in Figure 1 below. These are the upstream water passage, the turbine guarantee
domain, and the downstream water passage.

62006 © IEC:2010 – 11 –
Head water level
(HWL)
P
out
Transformer
U2
P
L,tf
Generator
U1
Exciter (P )
L,ex
electr./mech.
P
gen
P
L,gn
E- el
Auxiliary device (P )
L,ax
Sub system
P
L,ax
E-mech
Transmission (gear/belt)
P
L,tr
Turbine bearing
P
Tail water level
t
(TWL)
Turbine setting
level
Upstream
Discharge
water passage
Turbine
Turbine guarantee domain
Downstream
water passage
High pressure
reference section 1
Low pressure
Reference datum
reference section 2
NOTE The losses in the upstream and downstream water passage are not part of the turbine losses.
Nevertheless, they may influence the hydraulic conditions in the turbine guarantee domain and lower the efficiency
of the turbine. Only the energy losses in the turbine guarantee section are to be considered when measuring the
efficiency of a turbine. If it is not possible to measure the energy in the reference section 1 and 2, the measuring
section should be changed in agreement with all parties.
The definition of the reference section 1 and 2 and that of net head and specific energy for the most common small
turbines is given in Annex B.
Figure 1 – Schematic layout of a hydroelectric installation (water to wire system)
4 Nature and extent of guarantees
4.1 Grouping of classes A, B, C
4.1.1 General
The scope of the measurement classes for hydroelectric installations is shown in Table 1.
z
z
z
T
z
Hg (gross head)
z
– 12 – 62006 © IEC:2010
Table 1 – Scope of classes A, B, and C
Class A    Normal (panel measurement) test program
Class B    Extended test program

Class C    Comprehensive test program

Measurement of class C B A Clause
Safety tests (commissioning)  5
Pre-start tests (dry test) yes yes yes 5.1

Closing devices (dry and wet tests) yes yes yes 5.2
First run operation and control (wet tests) yes yes yes 5.3
Bearing run at rated speed yes yes yes 5.4
Emergency shutdown (no load) yes yes yes 5.5
Electrical protection yes yes yes 5.6
Overspeed test yes yes yes 5.7
Runaway test
...