Fans - Efficiency classification for fans (ISO 12759:2010, including Amd 1:2013)

This International Standard establishes a classification of fan efficiency for all fan types driven by motors with
an electrical input power range from 0,125 kW to 500 kW. This International Standard is applicable to bare
shaft and driven fans, as well as fans integrated into products. Fans integrated into products are measured as
stand-alone fans.
This International Standard is not applicable to:
a) fans for smoke and emergency smoke extraction;
b) fans for industrial processes;
c) fans for automotive application, trains and planes;
d) fans for potentially explosive atmospheres;
e) box fans, powered roof ventilators and air curtains;
f) jet fans for use in car parks and tunnel ventilation.

Ventilatoren - Effizienzklassifizierung für Ventilatoren (ISO 12759:2010, einschließlich Amd 1:2013)

Diese Internationale Norm legt Anforderungen für die Klassifizierung von Wirkungsgraden für alle motorbetriebenen Ventilatortypen mit einer elektrischen Eingangsleistung im Bereich von 0,125 kW bis 500 kW fest. Diese Internationale Norm ist anwendbar auf Ventilatoren mit freiliegender Welle und angetriebene Ventilatoren, sowie produktintegrierte Ventilatoren. Produktintegrierte Ventilatoren werden als eigenständige (stand-alone) Ventilatoren behandelt.
Diese Internationale Norm gilt nicht für:
a)   Brandgas  und Entrauchungsventilatoren;
b)   Ventilatoren für industrielle Verfahren;
c)   Ventilatoren für die Anwendung in Fahrzeugen, Zügen und Flugzeugen;
d)   Ventilatoren für den Einsatz in explosionsgefährdeten Bereichen;
e)   Kastenventilatoren, Dachventilatoren und Luftschleiergeräte;
f)   Strahlventilatoren für den Einsatz in Parkhäusern und zur Tunnelbelüftung.

Ventilateurs - Classification du rendement des ventilateurs (ISO 12759:2010, y compris Amd 1:2013)

L'ISO 12759:2010 établit une classification du rendement de tous les types de ventilateurs entraînés par des moteurs dont la puissance électrique absorbée est comprise entre 0,125 kW et 500 kW. Elle est applicable aux ventilateurs à arbre nu et à entraînement, ainsi qu'aux ventilateurs intégrés à des produits. Ces derniers sont mesurés en tant que ventilateurs autonomes.
Elle n'est pas applicable aux ventilateurs utilisés pour l'extraction des fumées et le désenfumage; aux ventilateurs pour les procédés industriels; aux ventilateurs pour les applications automobiles, les trains, les avions, etc.; aux ventilateurs placés en atmosphères potentiellement explosives; aux ventilateurs en caisson, aux tourelles d'extraction motorisées, aux rideaux d'air; ni aux ventilateurs utilisés dans les parkings et pour la ventilation des tunnels.

Ventilatorji - Klasifikacija učinkovitosti za ventilatorje (ISO 12759:2010, vključuje dopolnilo A1:2013)

Ta mednarodni standard določa klasifikacijo učinkovitosti za ventilatorje za vse vrste ventilatorjev z motorji z razponom električne vhodne moči od 0,125 kW do 500 kW. Ta mednarodni standard se uporablja za ventilatorje z golo gredjo in pogonom ter ventilatorje, vgrajene v izdelke. Ventilatorji, vgrajeni v izdelke, se merijo kot samostojni ventilatorji.
Ta evropski standard ne velja za:
a) ventilatorje za dim in odstranjevanje plina v izrednih razmerah;
b) ventilatorje za industrijske procese;
c) ventilatorje za avtomobilsko uporabo, vlake in letala;
d) ventilatorje za potencialno eksplozivne atmosfere;
e) ventilatorje v pravokotnem ohišju, napajane strešne ventilatorje in zračne zavese;
f) potisne ventilatorje za uporabo na avtomobilskih parkiriščih in za prezračevanje v predorih.

General Information

Status
Withdrawn
Public Enquiry End Date
09-Apr-2015
Publication Date
09-Sep-2015
Withdrawal Date
05-Jan-2020
Technical Committee
Current Stage
9900 - Withdrawal (Adopted Project)
Start Date
30-Dec-2019
Due Date
22-Jan-2020
Completion Date
06-Jan-2020

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 12759:2015
01-oktober-2015
9HQWLODWRUML.ODVLILNDFLMDXþLQNRYLWRVWL]DYHQWLODWRUMH ,62YNOMXþXMH
GRSROQLOR$
Fans - Efficiency classification for fans (ISO 12759:2010, including Amd 1:2013)
Ventilatoren - Effizienzklassifizierung für Ventilatoren (ISO 12759:2010, einschließlich
Amd 1:2013)
Ventilateurs - Classification du rendement des ventilateurs (ISO 12759:2010, y compris
Amd 1:2013)
Ta slovenski standard je istoveten z: EN ISO 12759:2015
ICS:
23.120 =UDþQLNL9HWUQLNL.OLPDWVNH Ventilators. Fans. Air-
QDSUDYH conditioners
SIST EN ISO 12759:2015 en,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 12759:2015

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SIST EN ISO 12759:2015

EUROPEAN STANDARD
EN ISO 12759

NORME EUROPÉENNE

EUROPÄISCHE NORM
July 2015
ICS 23.120
English Version
Fans - Efficiency classification for fans (ISO 12759:2010,
including Amd 1:2013)
Ventilateurs - Classification du rendement des ventilateurs Ventilatoren - Effizienzklassifizierung für Ventilatoren (ISO
(ISO 12759:2010, y compris Amd 1:2013) 12759:2010, einschließlich Amd 1:2013)
This European Standard was approved by CEN on 16 July 2015.

CEN 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 CEN-CENELEC Management Centre or to any CEN 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 CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.

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





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 12759:2015 E
worldwide for CEN national Members.

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SIST EN ISO 12759:2015
EN ISO 12759:2015 (E)
Contents Page
European foreword .3

2

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SIST EN ISO 12759:2015
EN ISO 12759:2015 (E)
European foreword
The text of ISO 12759:2010, including Amd 1:2013, has been prepared by Technical Committee ISO/TC 117
“Fans” of the International Organization for Standardization (ISO) and has been taken over as EN ISO
12759:2015 by Technical Committee CEN/TC 156 “Ventilation for buildings” the secretariat of which is held by
BSI
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by January 2016, and conflicting national standards shall be withdrawn at
the latest by January 2016.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 12759:2010, including Amd 1:2013, has been approved by CEN as EN ISO 12759:2015
without any modification.
3

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SIST EN ISO 12759:2015

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SIST EN ISO 12759:2015

INTERNATIONAL ISO
STANDARD 12759
First edition
2010-12-15


Fans — Efficiency classification for fans
Ventilateurs — Classification du rendement des ventilateurs





Reference number
ISO 12759:2010(E)
©
ISO 2010

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
PDF disclaimer
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All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
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Published in Switzerland

ii © ISO 2010 – All rights reserved

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
3.1 Fans — General .2
3.2 Fan or test installation categories according to the arrangement of ducting .3
3.3 Fans — Definitions relating to calculations.3
3.4 Definitions relating to fan efficiency .5
3.5 Fan efficiency grades.6
4 Symbols and units.6
5 Fan installation, efficiency and tolerance.7
5.1 General .7
5.2 Use of installation categories .9
5.3 Calculation of efficiency .9
5.4 Tolerances.10
6 Ratings.10
6.1 General .10
6.2 Bare shaft fans.10
6.3 Driven fans .13
Annex A (normative) Energy efficiency grades for bare shaft fans .20
Annex B (normative) Calculation method to determine efficiency of component parts.21
Annex C (informative) Variation of fan performance between installation categories.26
Annex D (informative) Input power calculation for driven fans at design point.27
Annex E (informative) Selection of fans for best efficiency .35
Annex F (informative) Determination of efficiency grade for a driven fan.38
Annex G (informative) Explanatory note .40
Bibliography.42

© ISO 2010 – All rights reserved iii

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 12759 was prepared by Technical Committee ISO/TC 117, Fans.
iv © ISO 2010 – All rights reserved

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
Introduction
The last decade has seen not only an escalation in the price, but also an increasing recognition of the finite life
of many of the fossil fuels in use. There is also a belief that climatic change is due to an increase in the levels
of carbon dioxide in the atmosphere. This has lead to many nations reviewing methods of energy generation
and usage.
Therefore, there is a need to promote energy efficiency in order to maintain economic growth. This requires
better selection of equipment by users and better design of this equipment by manufacturers.
Fans of all types are used for ventilation and air conditioning, process engineering (drying, pneumatic
conveying), combustion air supply and agriculture, etc. Indeed, the energy usage by fans has been calculated
as nearly 20 % of worldwide demand.
The fan industry is of a global nature, with a considerable degree of exporting and licensing. To ensure that
defined fan performance characteristics are common throughout the world, a series of International Standards
has been developed. It is the belief of the industry that there is a need for the recognition of minimum
efficiency standards. To encourage their implementation, a classification system is proposed which
incorporates a series of efficiency bands. With improvements in technology and manufacturing processes, the
minimum efficiency levels can be reviewed and increased over time.
This International Standard can be used by legislators or regulatory bodies for defining future energy saving
targets.

© ISO 2010 – All rights reserved v

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SIST EN ISO 12759:2015

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SIST EN ISO 12759:2015
INTERNATIONAL STANDARD ISO 12759:2010(E)

Fans — Efficiency classification for fans
1 Scope
This International Standard establishes a classification of fan efficiency for all fan types driven by motors with
an electrical input power range from 0,125 kW to 500 kW. This International Standard is applicable to bare
shaft and driven fans, as well as fans integrated into products. Fans integrated into products are measured as
stand-alone fans.
This International Standard is not applicable to:
a) fans for smoke and emergency smoke extraction;
b) fans for industrial processes;
c) fans for automotive application, trains and planes;
d) fans for potentially explosive atmospheres;
e) box fans, powered roof ventilators and air curtains;
f) jet fans for use in car parks and tunnel ventilation.
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.
ISO 5801:2007, Industrial fans — Performance testing using standardized airways
ISO 13348:2007, Industrial fans — Tolerances, methods of conversion and technical data presentation
ISO 13349:2010, Fans — Vocabulary and definitions of categories
IEC 60034-2-1, Rotating electrical machines — Part 2-1: Standard methods for determining losses and
efficiency from tests (excluding machines for traction vehicles)
IEC 60034-30, Rotating electrical machines — Part 30: Efficiency classes of single-speed, three-phase, cage-
induction motors
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 13349 and the following apply.
NOTE See, in particular, ISO 13349:2010, Tables 4 and 5, as well as the associated equations in Clause 5 of this
International Standard and ISO 5801.
© ISO 2010 – All rights reserved 1

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
3.1 Fans — General
3.1.1
fan
rotary bladed machine which receives mechanical energy and utilizes it by means of one or more impellers
fitted with blades to maintain a continuous flow of air or other gas passing through it and whose work per unit
mass does not normally exceed 25 kJ/kg
NOTE 1 Fans are defined according to their installation category, function, fluid path and operating conditions.
NOTE 2 Adapted from ISO 13349:2010, definition 3.1.1.
3.1.2
fan size
maximum impeller tip diameter, D, on which the design of the fan is based
3.1.3
drive
〈transmission and motor/control system〉 device used to power the fan, including motor, mechanical
transmission and motor/control system
NOTE 1 Examples of mechanical transmission are belt drive and couplings.
NOTE 2 Examples of a motor or control system are variable frequency controller and electronic commutator.
3.1.4
bare shaft fan
fan without drives, attachments or accessories (appurtenance)
See Figure 1.
NOTE Adapted from ISO 13349:2010, definition 3.1.2.
3.1.5
driven fan
one or more impellers fitted to or connected to a motor, with or without a drive mechanism, a housing and a
means of variable speed drive
See Figure 2.
NOTE Adapted from ISO 13349:2010, definition 3.1.3.
3.1.6
air
abbreviated term for the expression “air or other gas”
[ISO 13349:2010, definition 3.2]
3.1.7
standard air
3
atmospheric air having a density of exactly 1,2 kg/m
NOTE 1 Atmospheric air at a temperature of 16 °C, a pressure of 100 000 Pa and a relative humidity of 65 %, has a
3
density of 1,2 kg/m , but these conditions do not form part of the definition.
NOTE 2 Adapted from ISO 13349:2010, definition 3.3.
2 © ISO 2010 – All rights reserved

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
3.2 Fan or test installation categories according to the arrangement of ducting
See Figure 3 and ISO 13349.
3.2.1
installation category A
installation with free inlet and free outlet
3.2.2
installation category B
installation with free inlet and ducted outlet
3.2.3
installation category C
installation with ducted inlet and free outlet
3.2.4
installation category D
installation with ducted inlet and ducted outlet
3.3 Fans — Definitions relating to calculations
3.3.1
average density at fan inlet
ρ
1
fluid density calculated from the absolute pressure and the static temperature
3.3.2
atmospheric pressure
p
a
pressure, measured with respect to absolute zero pressure, which is exerted at a point at rest relative to the
air around it
3.3.3
fan pressure
p
f
difference between the stagnation pressure at the fan outlet and the stagnation pressure at the fan inlet
3.3.4
fan static pressure
p
sf
conventional quantity defined as the fan pressure minus the fan dynamic pressure at the fan outlet corrected
by the Mach factor
3.3.5
absolute stagnation pressure at a point
p
sg
absolute pressure which would be measured at a point in a flowing gas, if it were brought to rest via an
isentropic process
3.3.6
conventional dynamic pressure at a point
p
d
pressure calculated from the velocity and the density of the air at the point
© ISO 2010 – All rights reserved 3

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
3.3.7
fan dynamic pressure at the fan outlet
p
d2
conventional dynamic pressure at the fan outlet calculated from the mass flow rate, the average gas density at
the outlet and the outlet area
3.3.8
mass flow rate
q
m
mean value, over time, of the mass of air which passes through the specified airway cross-section per unit of
time
3.3.9
inlet volume flow rate
q
v1
mass flow rate at the inlet divided by the corresponding mean value, over time, of the average density at the
inlet
3.3.10
fan work per unit mass
W
m
increase in mechanical energy per unit mass of fluid passing through the fan
3.3.11
compressibility coefficient
k
p
ratio of the mechanical work done by the fan on the air to the work that would be done on an incompressible
fluid with the same mass flow, inlet density and pressure ratio
3.3.12
fan air power
P
u
conventional output power which is the product of the mass flow rate and the fan work per unit mass, or the
product of the inlet volume flow rate, the compressibility coefficient and the fan pressure
3.3.13
fan static air power
P
us
conventional output power which is the product of the mass flow rate and the fan static work per unit mass, or
the product of the inlet volume flow rate, the compressibility coefficient and the fan static pressure
3.3.14
impeller power
P
r
mechanical power supplied to the fan impeller
NOTE This is applicable to direct driven impellers which are open (as in, for example, a plenum fan) or enclosed in a
housing.
3.3.15
nominal motor power
P
N
rated output power of an electric motor
3.3.16
fan shaft power
P
a
mechanical power supplied to the fan shaft
4 © ISO 2010 – All rights reserved

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
3.3.17
motor output power
P
o
shaft power output of the motor or other prime mover
3.3.18
motor input power
P
e
electrical power supplied to the fan's motor
3.3.19
drive/control electrical input power
P
ed
electrical power supplied to the motor's drive or control
3.4 Definitions relating to fan efficiency
3.4.1
fan impeller efficiency
η
r
fan air power divided by the impeller power, P
r
3.4.2
fan shaft efficiency
η
a
fan air power divided by the fan shaft power, P
a
3.4.3
overall efficiency
η
e
fan air power divided by the input power for the fan and motor
3.4.4
overall static efficiency
η
es
fan static air power divided by the input power for the fan and motor
3.4.5
overall efficiency drive
η
ed
〈transmission and motor/control system〉 fan air power divided by the input power for the fan and motor
combination which include transmission or variable speed controls to take account of all losses within the fan
assembly
3.4.6
overall static efficiency drive
η
esd
〈transmission and motor/control system〉 fan static air power divided by the input power for the fan and motor
combination which include transmission or variable speed controls to take account of all losses within the fan
assembly
NOTE 1 The efficiency can be referred to the installation category (see Figure 3 and ISO 13349).
NOTE 2 Efficiency can be expressed as a proportion of unity. To obtain a per cent value, multiply the efficiency result
by 100.
© ISO 2010 – All rights reserved 5

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
3.4.7
optimum efficiency
η
opt
maximum efficiency achieved on the fan air characteristic with all operational parameters, except the air
system resistance, being fixed
3.4.8
compensation factor
C
c
factor, used in the determination of efficiencies for fans incorporating or fitted with variable speed drives
See Figure 5.
3.5 Fan efficiency grades
3.5.1
fan efficiency grade
FEG
efficiency grade for a bare shaft fan
NOTE The definitions given in 3.4.1 and 3.4.2 can apply.
3.5.2
fan motor efficiency grade
FMEG
efficiency grade for a driven fan
NOTE The definitions given in 3.4.3, 3.4.4, 3.4.5 and 3.4.6 can apply.
3.5.3
grade number
N
G
integer of the FMEG
4 Symbols and units
For the purposes of this document, the symbols and primary units in Table 1 for the parameters listed apply.
Table 1 — Symbols and units
Symbol Description Unit
C Compensation factor to account for energy savings at part load —
c
C Compensation factor to account for suboptimal matching of components —
m
D Maximum impeller tip diameter (fan size) mm
k Compressibility coefficient —
p
N Grade number (integer) of the FMEG —
G
P Fan shaft power W
a
P Power loss in bearings W
b
P Motor input power W
e
P Drive/control electrical input power W
ed
P Nominal motor power W
N
P Motor output power W
o
6 © ISO 2010 – All rights reserved

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
Table 1 (continued)
Symbol Description Unit
P Impeller power W
r
3
P Specific fan power kW/(m /s) or W/(l/s)
sf
P Fan air power W
u
P Fan static air power W
us
p Atmospheric pressure Pa
a
p Conventional dynamic pressure at a point Pa
d
p Fan dynamic pressure at the fan outlet Pa
d2
p Fan pressure Pa
f
p Fan static pressure Pa
sf
p Absolute stagnation pressure at a point Pa
sg
q Mass flow rate kg/s
m
3
q Inlet volume flow rate m /s
v1
W Fan work per unit mass J/kg
m
η Fan shaft efficiency Expressed as a decimal
a
η Fan bearing efficiency Expressed as a decimal
b
η Variable speed drive efficiency Expressed as a decimal
c
η Overall efficiency for fans without drives Expressed as a decimal
e
η Overall efficiency for fans with drives Expressed as a decimal
ed
η Overall static efficiency for fans without drives Expressed as a decimal
es
η Overall static efficiency for fans with drives Expressed as a decimal
esd
η Motor efficiency Expressed as a decimal
m
η Optimum efficiency Expressed as a decimal
opt
η Fan impeller efficiency Expressed as a decimal
r
η Drive mechanism (transmission efficiency) Expressed as a decimal
T
3
ρ Average density at fan inlet kg/m
1
NOTE Efficiency in per cent (%) divided by 100 equals the efficiency, expressed as a decimal.

5 Fan installation, efficiency and tolerance
5.1 General
Fans range from the purpose-built single fan to the series-produced certified ranges, which are manufactured
in large quantities. A fan can be an impeller on a shaft with no drive mechanism attached (i.e. bare shaft fan)
(see Figure 1), or a motor attached to a drive system attached to an impeller within an impeller housing. In
that case, it can be supplemented by a volume control, such as a variable speed control or guide vanes (i.e.
driven fan) (see Figure 2).
The variation in design has led to efficiency being defined in a number of ways to suit the demands of the fan
type and the market.
© ISO 2010 – All rights reserved 7

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SIST EN ISO 12759:2015
ISO 12759:2010(E)

Figure 1 — Example of a bare shaft centrifugal fan


Key
P fan air power
u
P drive/control electrical input power
ed
a
Variable speed device loss (heat). [The variable speed device can be fitted or not (see Clause 6).]
b
Motor losses (heat).
c
Belt losses (heat).
d
Bearing losses (heat).
e
Impeller and casing aerodynamic losses (heat).
Figure 2 — Example of a driven fan showing power losses

8 © ISO 2010 – All rights reserved

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
5.2 Use of installation categories
Fan efficiency ratings are frequently specific for each standardized test installation category.
If a fan is designed for a single installation category, its rated efficiency grade shall refer to that particular test
installation category, and this shall be clearly identified.
If a fan is suitable for use with different installation categories, the fan efficiency grade shall be based on the
efficiency ratings referring to the most suitable category, and this shall be clearly identified.
To determine the operating point of the fan, four installation categories shall be considered (see Figure 3). For
details of test methods, see the following clauses of ISO 5801:2007:
a) category A installations — Clause 30;
b) category B installations — Clause 31;
c) category C installations — Clause 32;
d) category D installations — Clause 33.
The standardized installation category used for rating the fan shall be clearly stated (see Annex C).
The motor input power and motor output power may be measured or determined using the methods given in
ISO 5801. Installation category E is not included in this International Standard.

a)  Category A b)  Category B c)  Category C d)  Category D
Figure 3 — Installation categories
5.3 Calculation of efficiency
5.3.1 The fan air power and efficiency are calculated from fan work per unit mass in accordance with
ISO 5801:2007, 14.8.1.
5.3.2 For a bare shaft fan where bearing losses are excluded, the efficiency is given by Equation (1):
η = P /P (1)
r u r
5.3.3 For a bare shaft fan where bearing losses are included, the efficiency is given by Equation (2):
η = P /P (2)
a u a
5.3.4 For a driven fan that does not include a variable speed drive, where the input power can be
determined, the overall efficiency is given by Equation (3) or (4):
η = P /P (3)
e u e
η = P /P (4)
es us e
© ISO 2010 – All rights reserved 9

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SIST EN ISO 12759:2015
ISO 12759:2010(E)
5.3.5 For a driven fan that includes a variable speed drive, where the input power can be determined, the
overall efficiency is given by Equation (5) or (6):
η = C × P / P (5)
ed c u ed
P
us
η =×C (6)
esd c
P
ed
NOTE The use of fan pressure or fan static pressure determines the appropriate efficiency grade according to the
installation category.
5.4 Tolerances
At each stage of the fan design and manufacturing cycle, including conversion from prototype performance
data or calculation, fabrication and testing of a purpose-designed fan, finite uncertainties prevail and
acceptance tolerances shall be applied.
Any test for fan performance is subject to error, and the range within which these testing errors can be
expected to lie is defined numerically as the uncertainty of measurement. In addition, the true performance of
the fan
...

SLOVENSKI STANDARD
kSIST FprEN ISO 12759:2015
01-marec-2015
9HQWLODWRUML.ODVLILNDFLMDXþLQNRYLWRVWL]DYHQWLODWRUMH ,62$
Fans - Efficiency classification for fans (ISO 12759:2010 + A1:2013)
Ventilatoren - Effizienzklassifizierung für Ventilatoren (ISO 12759:2010 + A1:2013)
Ventilateurs - Classification du rendement des ventilateurs (ISO 12759:2010 + A1:2013)
Ta slovenski standard je istoveten z: FprEN ISO 12759
ICS:
23.120 =UDþQLNL9HWUQLNL.OLPDWVNH Ventilators. Fans. Air-
QDSUDYH conditioners
kSIST FprEN ISO 12759:2015 en,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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kSIST FprEN ISO 12759:2015

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kSIST FprEN ISO 12759:2015

EUROPEAN STANDARD
FINAL DRAFT
FprEN ISO 12759
NORME EUROPÉENNE

EUROPÄISCHE NORM

January 2015
ICS 23.120
English Version
Fans - Efficiency classification for fans (ISO 12759:2010 +
A1:2013)
Ventilateurs - Classification du rendement des ventilateurs Ventilatoren - Effizienzklassifizierung für Ventilatoren (ISO
(ISO 12759:2010 + A1:2013) 12759:2010 + A1:2013)
This draft European Standard is submitted to CEN members for unique acceptance procedure. It has been drawn up by the Technical
Committee CEN/TC 156.

If this draft becomes a European Standard, CEN 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.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other language
made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

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

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2015 CEN All rights of exploitation in any form and by any means reserved Ref. No. FprEN ISO 12759:2015 E
worldwide for CEN national Members.

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kSIST FprEN ISO 12759:2015
FprEN ISO 12759:2015 (E)
Contents
Page
Foreword .3


2

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kSIST FprEN ISO 12759:2015
FprEN ISO 12759:2015 (E)
Foreword
The text of ISO 12759:2010 + A1:2013 has been prepared by Technical Committee ISO/TC 117 “Fans” of the
International Organization for Standardization (ISO) and has been taken over as FprEN ISO 12759:2015 by
Technical Committee CEN/TC 156 “Ventilation for buildings” the secretariat of which is held by BSI.
This document is currently submitted to the Unique Acceptance Procedure.
Endorsement notice
The text of ISO 12759:2010 + A1:2013 has been approved by CEN as FprEN ISO 12759:2015 without any
modification.

3

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kSIST FprEN ISO 12759:2015

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kSIST FprEN ISO 12759:2015

INTERNATIONAL ISO
STANDARD 12759
First edition
2010-12-15


Fans — Efficiency classification for fans
Ventilateurs — Classification du rendement des ventilateurs





Reference number
ISO 12759:2010(E)
©
ISO 2010

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
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All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
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Published in Switzerland

ii © ISO 2010 – All rights reserved

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
Contents Page
Foreword .iv
Introduction.v
1 Scope.1
2 Normative references.1
3 Terms and definitions .1
3.1 Fans — General .2
3.2 Fan or test installation categories according to the arrangement of ducting .3
3.3 Fans — Definitions relating to calculations.3
3.4 Definitions relating to fan efficiency .5
3.5 Fan efficiency grades.6
4 Symbols and units.6
5 Fan installation, efficiency and tolerance.7
5.1 General .7
5.2 Use of installation categories .9
5.3 Calculation of efficiency .9
5.4 Tolerances.10
6 Ratings.10
6.1 General .10
6.2 Bare shaft fans.10
6.3 Driven fans .13
Annex A (normative) Energy efficiency grades for bare shaft fans .20
Annex B (normative) Calculation method to determine efficiency of component parts.21
Annex C (informative) Variation of fan performance between installation categories.26
Annex D (informative) Input power calculation for driven fans at design point.27
Annex E (informative) Selection of fans for best efficiency .35
Annex F (informative) Determination of efficiency grade for a driven fan.38
Annex G (informative) Explanatory note .40
Bibliography.42

© ISO 2010 – All rights reserved iii

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies
(ISO member bodies). The work of preparing International Standards is normally carried out through ISO
technical committees. Each member body interested in a subject for which a technical committee has been
established has the right to be represented on that committee. International organizations, governmental and
non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the
International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. ISO shall not be held responsible for identifying any or all such patent rights.
ISO 12759 was prepared by Technical Committee ISO/TC 117, Fans.
iv © ISO 2010 – All rights reserved

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
Introduction
The last decade has seen not only an escalation in the price, but also an increasing recognition of the finite life
of many of the fossil fuels in use. There is also a belief that climatic change is due to an increase in the levels
of carbon dioxide in the atmosphere. This has lead to many nations reviewing methods of energy generation
and usage.
Therefore, there is a need to promote energy efficiency in order to maintain economic growth. This requires
better selection of equipment by users and better design of this equipment by manufacturers.
Fans of all types are used for ventilation and air conditioning, process engineering (drying, pneumatic
conveying), combustion air supply and agriculture, etc. Indeed, the energy usage by fans has been calculated
as nearly 20 % of worldwide demand.
The fan industry is of a global nature, with a considerable degree of exporting and licensing. To ensure that
defined fan performance characteristics are common throughout the world, a series of International Standards
has been developed. It is the belief of the industry that there is a need for the recognition of minimum
efficiency standards. To encourage their implementation, a classification system is proposed which
incorporates a series of efficiency bands. With improvements in technology and manufacturing processes, the
minimum efficiency levels can be reviewed and increased over time.
This International Standard can be used by legislators or regulatory bodies for defining future energy saving
targets.

© ISO 2010 – All rights reserved v

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kSIST FprEN ISO 12759:2015

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kSIST FprEN ISO 12759:2015
INTERNATIONAL STANDARD ISO 12759:2010(E)

Fans — Efficiency classification for fans
1 Scope
This International Standard establishes a classification of fan efficiency for all fan types driven by motors with
an electrical input power range from 0,125 kW to 500 kW. This International Standard is applicable to bare
shaft and driven fans, as well as fans integrated into products. Fans integrated into products are measured as
stand-alone fans.
This International Standard is not applicable to:
a) fans for smoke and emergency smoke extraction;
b) fans for industrial processes;
c) fans for automotive application, trains and planes;
d) fans for potentially explosive atmospheres;
e) box fans, powered roof ventilators and air curtains;
f) jet fans for use in car parks and tunnel ventilation.
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.
ISO 5801:2007, Industrial fans — Performance testing using standardized airways
ISO 13348:2007, Industrial fans — Tolerances, methods of conversion and technical data presentation
ISO 13349:2010, Fans — Vocabulary and definitions of categories
IEC 60034-2-1, Rotating electrical machines — Part 2-1: Standard methods for determining losses and
efficiency from tests (excluding machines for traction vehicles)
IEC 60034-30, Rotating electrical machines — Part 30: Efficiency classes of single-speed, three-phase, cage-
induction motors
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 13349 and the following apply.
NOTE See, in particular, ISO 13349:2010, Tables 4 and 5, as well as the associated equations in Clause 5 of this
International Standard and ISO 5801.
© ISO 2010 – All rights reserved 1

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
3.1 Fans — General
3.1.1
fan
rotary bladed machine which receives mechanical energy and utilizes it by means of one or more impellers
fitted with blades to maintain a continuous flow of air or other gas passing through it and whose work per unit
mass does not normally exceed 25 kJ/kg
NOTE 1 Fans are defined according to their installation category, function, fluid path and operating conditions.
NOTE 2 Adapted from ISO 13349:2010, definition 3.1.1.
3.1.2
fan size
maximum impeller tip diameter, D, on which the design of the fan is based
3.1.3
drive
〈transmission and motor/control system〉 device used to power the fan, including motor, mechanical
transmission and motor/control system
NOTE 1 Examples of mechanical transmission are belt drive and couplings.
NOTE 2 Examples of a motor or control system are variable frequency controller and electronic commutator.
3.1.4
bare shaft fan
fan without drives, attachments or accessories (appurtenance)
See Figure 1.
NOTE Adapted from ISO 13349:2010, definition 3.1.2.
3.1.5
driven fan
one or more impellers fitted to or connected to a motor, with or without a drive mechanism, a housing and a
means of variable speed drive
See Figure 2.
NOTE Adapted from ISO 13349:2010, definition 3.1.3.
3.1.6
air
abbreviated term for the expression “air or other gas”
[ISO 13349:2010, definition 3.2]
3.1.7
standard air
3
atmospheric air having a density of exactly 1,2 kg/m
NOTE 1 Atmospheric air at a temperature of 16 °C, a pressure of 100 000 Pa and a relative humidity of 65 %, has a
3
density of 1,2 kg/m , but these conditions do not form part of the definition.
NOTE 2 Adapted from ISO 13349:2010, definition 3.3.
2 © ISO 2010 – All rights reserved

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
3.2 Fan or test installation categories according to the arrangement of ducting
See Figure 3 and ISO 13349.
3.2.1
installation category A
installation with free inlet and free outlet
3.2.2
installation category B
installation with free inlet and ducted outlet
3.2.3
installation category C
installation with ducted inlet and free outlet
3.2.4
installation category D
installation with ducted inlet and ducted outlet
3.3 Fans — Definitions relating to calculations
3.3.1
average density at fan inlet
ρ
1
fluid density calculated from the absolute pressure and the static temperature
3.3.2
atmospheric pressure
p
a
pressure, measured with respect to absolute zero pressure, which is exerted at a point at rest relative to the
air around it
3.3.3
fan pressure
p
f
difference between the stagnation pressure at the fan outlet and the stagnation pressure at the fan inlet
3.3.4
fan static pressure
p
sf
conventional quantity defined as the fan pressure minus the fan dynamic pressure at the fan outlet corrected
by the Mach factor
3.3.5
absolute stagnation pressure at a point
p
sg
absolute pressure which would be measured at a point in a flowing gas, if it were brought to rest via an
isentropic process
3.3.6
conventional dynamic pressure at a point
p
d
pressure calculated from the velocity and the density of the air at the point
© ISO 2010 – All rights reserved 3

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
3.3.7
fan dynamic pressure at the fan outlet
p
d2
conventional dynamic pressure at the fan outlet calculated from the mass flow rate, the average gas density at
the outlet and the outlet area
3.3.8
mass flow rate
q
m
mean value, over time, of the mass of air which passes through the specified airway cross-section per unit of
time
3.3.9
inlet volume flow rate
q
v1
mass flow rate at the inlet divided by the corresponding mean value, over time, of the average density at the
inlet
3.3.10
fan work per unit mass
W
m
increase in mechanical energy per unit mass of fluid passing through the fan
3.3.11
compressibility coefficient
k
p
ratio of the mechanical work done by the fan on the air to the work that would be done on an incompressible
fluid with the same mass flow, inlet density and pressure ratio
3.3.12
fan air power
P
u
conventional output power which is the product of the mass flow rate and the fan work per unit mass, or the
product of the inlet volume flow rate, the compressibility coefficient and the fan pressure
3.3.13
fan static air power
P
us
conventional output power which is the product of the mass flow rate and the fan static work per unit mass, or
the product of the inlet volume flow rate, the compressibility coefficient and the fan static pressure
3.3.14
impeller power
P
r
mechanical power supplied to the fan impeller
NOTE This is applicable to direct driven impellers which are open (as in, for example, a plenum fan) or enclosed in a
housing.
3.3.15
nominal motor power
P
N
rated output power of an electric motor
3.3.16
fan shaft power
P
a
mechanical power supplied to the fan shaft
4 © ISO 2010 – All rights reserved

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
3.3.17
motor output power
P
o
shaft power output of the motor or other prime mover
3.3.18
motor input power
P
e
electrical power supplied to the fan's motor
3.3.19
drive/control electrical input power
P
ed
electrical power supplied to the motor's drive or control
3.4 Definitions relating to fan efficiency
3.4.1
fan impeller efficiency
η
r
fan air power divided by the impeller power, P
r
3.4.2
fan shaft efficiency
η
a
fan air power divided by the fan shaft power, P
a
3.4.3
overall efficiency
η
e
fan air power divided by the input power for the fan and motor
3.4.4
overall static efficiency
η
es
fan static air power divided by the input power for the fan and motor
3.4.5
overall efficiency drive
η
ed
〈transmission and motor/control system〉 fan air power divided by the input power for the fan and motor
combination which include transmission or variable speed controls to take account of all losses within the fan
assembly
3.4.6
overall static efficiency drive
η
esd
〈transmission and motor/control system〉 fan static air power divided by the input power for the fan and motor
combination which include transmission or variable speed controls to take account of all losses within the fan
assembly
NOTE 1 The efficiency can be referred to the installation category (see Figure 3 and ISO 13349).
NOTE 2 Efficiency can be expressed as a proportion of unity. To obtain a per cent value, multiply the efficiency result
by 100.
© ISO 2010 – All rights reserved 5

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
3.4.7
optimum efficiency
η
opt
maximum efficiency achieved on the fan air characteristic with all operational parameters, except the air
system resistance, being fixed
3.4.8
compensation factor
C
c
factor, used in the determination of efficiencies for fans incorporating or fitted with variable speed drives
See Figure 5.
3.5 Fan efficiency grades
3.5.1
fan efficiency grade
FEG
efficiency grade for a bare shaft fan
NOTE The definitions given in 3.4.1 and 3.4.2 can apply.
3.5.2
fan motor efficiency grade
FMEG
efficiency grade for a driven fan
NOTE The definitions given in 3.4.3, 3.4.4, 3.4.5 and 3.4.6 can apply.
3.5.3
grade number
N
G
integer of the FMEG
4 Symbols and units
For the purposes of this document, the symbols and primary units in Table 1 for the parameters listed apply.
Table 1 — Symbols and units
Symbol Description Unit
C Compensation factor to account for energy savings at part load —
c
C Compensation factor to account for suboptimal matching of components —
m
D Maximum impeller tip diameter (fan size) mm
k Compressibility coefficient —
p
N Grade number (integer) of the FMEG —
G
P Fan shaft power W
a
P Power loss in bearings W
b
P Motor input power W
e
P Drive/control electrical input power W
ed
P Nominal motor power W
N
P Motor output power W
o
6 © ISO 2010 – All rights reserved

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
Table 1 (continued)
Symbol Description Unit
P Impeller power W
r
3
P Specific fan power kW/(m /s) or W/(l/s)
sf
P Fan air power W
u
P Fan static air power W
us
p Atmospheric pressure Pa
a
p Conventional dynamic pressure at a point Pa
d
p Fan dynamic pressure at the fan outlet Pa
d2
p Fan pressure Pa
f
p Fan static pressure Pa
sf
p Absolute stagnation pressure at a point Pa
sg
q Mass flow rate kg/s
m
3
q Inlet volume flow rate m /s
v1
W Fan work per unit mass J/kg
m
η Fan shaft efficiency Expressed as a decimal
a
η Fan bearing efficiency Expressed as a decimal
b
η Variable speed drive efficiency Expressed as a decimal
c
η Overall efficiency for fans without drives Expressed as a decimal
e
η Overall efficiency for fans with drives Expressed as a decimal
ed
η Overall static efficiency for fans without drives Expressed as a decimal
es
η Overall static efficiency for fans with drives Expressed as a decimal
esd
η Motor efficiency Expressed as a decimal
m
η Optimum efficiency Expressed as a decimal
opt
η Fan impeller efficiency Expressed as a decimal
r
η Drive mechanism (transmission efficiency) Expressed as a decimal
T
3
ρ Average density at fan inlet kg/m
1
NOTE Efficiency in per cent (%) divided by 100 equals the efficiency, expressed as a decimal.

5 Fan installation, efficiency and tolerance
5.1 General
Fans range from the purpose-built single fan to the series-produced certified ranges, which are manufactured
in large quantities. A fan can be an impeller on a shaft with no drive mechanism attached (i.e. bare shaft fan)
(see Figure 1), or a motor attached to a drive system attached to an impeller within an impeller housing. In
that case, it can be supplemented by a volume control, such as a variable speed control or guide vanes (i.e.
driven fan) (see Figure 2).
The variation in design has led to efficiency being defined in a number of ways to suit the demands of the fan
type and the market.
© ISO 2010 – All rights reserved 7

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)

Figure 1 — Example of a bare shaft centrifugal fan


Key
P fan air power
u
P drive/control electrical input power
ed
a
Variable speed device loss (heat). [The variable speed device can be fitted or not (see Clause 6).]
b
Motor losses (heat).
c
Belt losses (heat).
d
Bearing losses (heat).
e
Impeller and casing aerodynamic losses (heat).
Figure 2 — Example of a driven fan showing power losses

8 © ISO 2010 – All rights reserved

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
5.2 Use of installation categories
Fan efficiency ratings are frequently specific for each standardized test installation category.
If a fan is designed for a single installation category, its rated efficiency grade shall refer to that particular test
installation category, and this shall be clearly identified.
If a fan is suitable for use with different installation categories, the fan efficiency grade shall be based on the
efficiency ratings referring to the most suitable category, and this shall be clearly identified.
To determine the operating point of the fan, four installation categories shall be considered (see Figure 3). For
details of test methods, see the following clauses of ISO 5801:2007:
a) category A installations — Clause 30;
b) category B installations — Clause 31;
c) category C installations — Clause 32;
d) category D installations — Clause 33.
The standardized installation category used for rating the fan shall be clearly stated (see Annex C).
The motor input power and motor output power may be measured or determined using the methods given in
ISO 5801. Installation category E is not included in this International Standard.

a)  Category A b)  Category B c)  Category C d)  Category D
Figure 3 — Installation categories
5.3 Calculation of efficiency
5.3.1 The fan air power and efficiency are calculated from fan work per unit mass in accordance with
ISO 5801:2007, 14.8.1.
5.3.2 For a bare shaft fan where bearing losses are excluded, the efficiency is given by Equation (1):
η = P /P (1)
r u r
5.3.3 For a bare shaft fan where bearing losses are included, the efficiency is given by Equation (2):
η = P /P (2)
a u a
5.3.4 For a driven fan that does not include a variable speed drive, where the input power can be
determined, the overall efficiency is given by Equation (3) or (4):
η = P /P (3)
e u e
η = P /P (4)
es us e
© ISO 2010 – All rights reserved 9

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kSIST FprEN ISO 12759:2015
ISO 12759:2010(E)
5.3.5 For a driven fan that includes a variable speed drive, where the input power can be determined, the
overall efficiency is given by Equation (5) or (6):
η = C × P / P (5)
ed c u ed
P
us
η =×C (6)
esd c
P
ed
NOTE The use of fan pressure or fan static pressure determines the appropriate efficiency grade according to the
installation category.
5.4 Tolerances
At each stage of the fan design and manufacturing cycle, including conversion from prototype performance
data or calculation, fabrication and testing of a purpose-designed fan, finite uncertainties prevail and
acceptance tolerances shall be applied.
Any test for fan performance is subject to error, and the range within which these testing errors can be
expected to lie is defined numerically as the uncertainty of measurement. In addition, the true performance of
the fan (if it can be ascertained) would be found to differ from that of another nominally identical fan, owing to
inevitable variations in manufacture. The expected range of this manufacturing variation shall be added to the
uncertainty of measurement to determine the minimum tolerance required for a performance specification.
The tolerances given in ISO 13348:2007, Clause 5 (performance tolerances for purpose-designed fans and
series-produced non-certified fans), and ISO 13348:2007, Clause 6 (performance tolerances for series-
produced fans in certified ratings pro
...

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