Thermostatic radiator valves - Requirements and test methods

This European Standard specifies definitions, requirements and test methods for thermostatic radiator valves (referred to hereafter as thermostatic valves).
This standard applies to two port thermostatic valves with or without pre-setting facility and thermostatic integrated valves with or without pre-setting facility for fitting to radiators in wet central heating installations up to a water temperature of 120 °C and a nominal pressure of PN 10.
This standard further specifies the dimensions, the materials and the connection details of four series of straight and angle pattern thermostatic radiator valves of nominal pressure ≤ PN 10.
This standard can be used as reference in a CEN/CENELEC Certification Mark System on thermostatic radiator valves.

Thermostatische Heizkörperventile - Anforderungen und Prüfung

Diese Europäische Norm hat den Zweck, Begriffe, Anforderungen und Prüfungen für thermostatische Heizkörperventile (nachstehend Thermostatventile genannt) festzulegen.
Die vorliegende Norm ist auf thermostatische Zweiwegeventile mit oder ohne Voreinstellung und integrierte Thermostatventile mit oder ohne Voreinstellung anzuwenden, die zur Ausrüstung von Heizkörpern in Warmwasserheizungen bis zu einer Temperatur von 120 °C und bis zu einem Nenndruck von PN 10 dienen.
Die vorliegende Norm legt ferner die Maße, Werkstoffe und Ausführungen des Anschlusses von vier Reihen von thermostatischen Heizkörperventilen in Durchgangs- und Eckform mit Nenndruck ≤ PN 10 fest.
Auf diese Norm kann in einem CEN/CENELEC-Zertifizierungssystem für thermostatische Heizkörperventile Bezug genommen werden.

Robinets thermostatiques d'équipement du corps de chauffe - Exigences et méthodes d'essai

La présente Norme européenne spécifie les définitions, les exigences et les méthodes d'essai applicables aux robinets thermostatiques d'équipement du corps de chauffe (ci-après dénommés « robinets thermostatiques »).
La présente norme s'applique aux robinets thermostatiques à deux voies avec ou sans dispositif de pré-réglage et aux robinets thermostatiques intégrés avec ou sans dispositif de pré-réglage destinés à une adaptation sur corps de chauffe dans des installations de chauffage central à eau avec une température d'eau allant jusqu'à 120 °C et une pression nominale allant jusqu'à PN 10.
La présente norme spécifie en outre les dimensions, les matériaux et les détails concernant le raccordement de quatre séries de robinets thermostatiques d'équipement du corps de chauffe droits et d'équerre présentant une pression nominale inférieure ou égale à PN 10.
La présente norme peut être utilisée comme référence pour un Système de marques de certification CEN/CENELEC sur robinets thermostatiques d'équipement du corps de chauffe.

Termostatni ventili za ogrevala - Zahteve in preskusne metode

General Information

Status
Not Published
Public Enquiry End Date
28-Feb-2017
Technical Committee
Current Stage
98 - Abandoned project (Adopted Project)
Start Date
17-Jan-2018
Due Date
22-Jan-2018
Completion Date
17-Jan-2018

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SLOVENSKI STANDARD
oSIST prEN 215:2017
01-februar-2017
Termostatni ventili za ogrevala - Zahteve in preskusne metode
Thermostatic radiator valves - Requirements and test methods
Thermostatische Heizkörperventile - Anforderungen und Prüfung
Robinets thermostatiques d'équipement du corps de chauffe - Exigences et méthodes
d'essai
Ta slovenski standard je istoveten z: prEN 215
ICS:
23.060.01 Ventili na splošno Valves in general
91.140.10 Sistemi centralnega Central heating systems
ogrevanja
oSIST prEN 215:2017 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN 215:2017

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oSIST prEN 215:2017


DRAFT
EUROPEAN STANDARD
prEN 215
NORME EUROPÉENNE

EUROPÄISCHE NORM

January 2017
ICS 91.140.10 Will supersede EN 215:2004
English Version

Thermostatic radiator valves - Requirements and test
methods
Robinets thermostatiques d'équipement du corps de Thermostatische Heizkörperventile - Anforderungen
chauffe - Exigences et méthodes d'essai und Prüfung
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 130.

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
© 2017 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 215:2017 E
worldwide for CEN national Members.

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Contents Page
European foreword . 4
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Symbols and abbreviations . 13
5 Requirements . 14
5.1 Dimensions . 14
5.2 Mechanical properties . 14
5.2.1 Resistance to pressure, leak-tightness of the valve body assembly . 14
5.2.2 Leak-tightness of the stem seal . 14
5.2.3 Resistance of the valve body assembly to a bending moment . 14
5.2.4 Resistance of the temperature selector to a torque . 14
5.2.5 Resistance of the temperature selector to a bending moment . 14
5.2.6 Exchange of the stem seal. 14
5.3 Operating characteristics . 14
5.3.1 Nominal flow rate and flow rate at S-1 . 14
5.3.2 Characteristic flow rate at the minimum and maximum setting of the temperature
selector . 14
5.3.3 Characteristic flow rate for thermostatic valves having a pre-setting facility. 14
5.3.4 Sensor temperature at the minimum and maximum setting of the temperature
selector . 15
5.3.5 Hysteresis at the nominal flow rate . 15
5.3.6 Differential pressure influence . 15
5.3.7 Influence of the static pressure . 15
5.3.8 Temperature difference between temperature point S and the closing and opening
temperature respectively . 15
5.3.9 Influence of ambient temperature on thermostatic valves with transmission
elements . 15
5.3.10 Water temperature effect. 15
5.3.11 Response time . 15
5.4 Endurance and temperature resistance . 15
5.4.1 Mechanical endurance . 15
5.4.2 Thermal endurance . 16
5.4.3 Temperature resistance . 16
6 Test apparatus and methods . 16
6.1 Test apparatus. 16
6.1.1 Apparatus to obtain the hydraulic data . 16
6.1.2 Apparatus for testing the thermostatic valve and the integrated thermostatic valve
in the water bath . 18
6.1.3 Apparatus for testing the thermostatic valve in the air stream . 19
6.2 Characteristic curves of thermostatic valves . 20
6.2.1 Determination of the characteristic curves . 20
6.2.2 Plotting of the theoretical curve . 22
6.3 Testing of mechanical properties . 23
6.3.1 Resistance to pressure, leak-tightness of the valve body assembly . 23
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6.3.2 Leak-tightness of the valve closed mechanically by means of the protection cap. . 24
6.3.3 Leak-tightness of the stem seal . 24
6.3.4 Resistance of the valve body assembly to a bending moment . 25
6.3.5 Resistance of the temperature selector to a torque . 26
6.3.6 Resistance of the temperature selector to a bending moment . 27
6.4 Testing of operating characteristics . 27
6.4.1 Characteristic data . 27
6.4.2 Endurance tests and temperature resistance test . 30
6.5 Test schedule . 31
7 Technical information to be published by the manufacturer . 33
Annex A (normative) Thermostatic Radiator Valves - Dimensions and details on connection . 35
A.1 General . 35
A.2 Dimensions . 35
A.3 Connection details . 37
A.4 Materials for body, tailpiece and nut . 37
A.5 Designation . 38
A.6 Marking (This marking does not cover possible certification marking) . 38
A.7 CA Value Calculation . 38
Annex B (informative) Degree of turbulence of the air current in a room . 39
Annex C (informative) Test block for thermostatic integrated valves . 40
Bibliography . 41

3

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European foreword
This document (prEN 215:2017) has been prepared by Technical Committee CEN/TC 130 “Space
heating appliances without integral heat sources”, the secretariat of which is held by UNI.
This document is currently submitted to the CEN Enquiry.
This document will supersede EN 215:2004.
This European Standard can be used as a reference for a CEN/CENELEC Certification Mark System on
radiator valves.
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1 Scope
This European Standard specifies definitions, requirements and test methods for thermostatic radiator
valves (referred to hereafter as thermostatic valves).
This standard applies to two port thermostatic valves with or without pre-setting facility and
thermostatic integrated valves with or without pre-setting facility for fitting to radiators in wet central
heating installations up to a water temperature of 120 °C and a nominal pressure of PN 10.
This standard further specifies the dimensions, the materials and the connection details of four series of
straight and angle pattern thermostatic radiator valves of nominal pressure ≤ PN 10.
This standard can be used as reference in a CEN/CENELEC Certification Mark System on thermostatic
radiator valves.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
EN 1982, Copper and copper alloys - Ingots and castings
EN 12164, Copper and copper alloys - Rod for free machining purposes
EN 12168, Copper and copper alloys - Hollow rod for free machining purposes
EN 12420, Copper and copper alloys - Forgings
EN 12449, Copper and copper alloys - Seamless, round tubes for general purposes
prEN 15316-2, Heating systems and water based cooling systems in buildings - Method for calculation of
system energy requirements and system efficiencies - Part 2: Space emission systems (heating and cooling)
EN ISO 228-1, Pipe threads where pressure-tight joints are not made on the threads - Part 1: Dimensions,
tolerances and designation (ISO 228-1)
ISO 7-1, Pipe threads where pressure-tight joints are made on the threads - Part 1: Dimensions, tolerances
and designation
ISO 965-1, ISO general purpose metric screw threads - Tolerances - Part 1: Principles and basic data.
ISO 7268, Pipe components - Definition of nominal pressure.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
thermostatic radiator valve
thermostatic head assembly and thermostatic valve assembly or the thermostatic integrated valve
assembly
Note 1 to entry: See Figure 1 for components of the thermostatic radiator valve.
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Key
A thermostatic head assembly 5 valve seat
B valve body assembly 6 union nut
1 sensor 7 tailpiece
2 temperature selector 8 valve stem
3 temperature selector scale 9 stem seal
4 valve disc 10 flow direction arrow
Figure 1 — Schematic drawing of the assembly of a thermostatic valve with integral sensor
3.1.1
sensor
part of the thermostatic valve that senses the temperature (controlled value)
Note 1 to entry: See Figure 2.
3.1.2
transmission unit
part of the thermostatic valve that converts a change of temperature or pressure of the sensor into a
linear movement of the valve stem
Note 1 to entry: See Figure 2.
3.1.3
transmission element
part of the thermostatic valve (e.g. capillary) that transmits the volume or pressure changes from the
sensor or temperature selector to the transmission unit
Note 1 to entry: See Figure 2.
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3.1.4
thermostatic element
section containing all parts that are filled with the expansion medium
EXAMPLE Sensor, transmission element and transmission unit, shown as cross hatched parts in Figure 2.


Key
1 sensor
2 transmission element
3 transmission unit
Figure 2 — Thermostatic element
3.1.5
protection cap
device that protects the valve stem and thread before the initial fitting of the thermostatic head
assembly
3.2
types of thermostatic head assembly
3.2.1
thermostatic valve with integral sensor
valve where the sensor, transmission unit and temperature selector constitute an assembly which is
incorporated with the valve body assembly
Note 1 to entry: See Figure 3.

Figure 3 — Thermostatic valve with integral sensor
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3.2.2
thermostatic valve with integral temperature selector and with remote sensor
valve where the temperature selector is incorporated within the valve but the sensor is separated from
the transmission unit, and there is a transmission element between the sensor and the transmission
unit
Note 1 to entry: See Figure 4.

Figure 4 — Thermostatic valve with integral temperature selector with remote sensor
3.2.3
thermostatic valve with the remote sensor incorporating the selector
valve where the sensor and temperature selector assembly is mounted remotely from the valve body
assembly and from the transmission unit, and there is a transmission element between the sensor and
the transmission unit
Note 1 to entry: See Figure 5.

Figure 5 — Thermostatic valve with the remote sensor incorporating the selector
3.2.4
thermostatic valve with remote sensor and remote selector
valve where both the sensor and the temperature selector are separate from each other and from the
valve body assembly with transmission unit, and there is a transmission element between the sensor
and the transmission unit and between the temperature selector and the transmission unit
Note 1 to entry: See Figure 6.
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Figure 6 — Thermostatic valve with remote sensor and remote selector
3.2.5
thermostatic valve with pre-setting
valve where a reduced flow rate can be obtained by means of mechanical pre-adjustment incorporated
in the valve body assembly
3.2.6
type of thermostatic integrated valve
embedded valve including valve seat
Note 1 to entry: See Figure 7.

Key
1 garniture
2 integrated valve assembly
3 packing seal
Figure 7 — Example of valve integrated in a radiator
3.3
types of connections
examples of connections used to fit the valve to the radiator and to the pipe work
Note 1 to entry: See Figure 8.
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Key
a) internal pipe thread and cone seated union
b) compression fitting and cone seated union
c) washered union connections
d) compression fittings
e) integrated valve
Figure 8 — Types of radiator valve connections
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3.4
operating characteristics
3.4.1
characteristic flow rate
q
m, s
water flow rate that is obtained at a temperature of point S-2K, and at a differential pressure of 10 kPa
(0,1 bar), at any desired setting
3.4.2
nominal flow rate
q
m, N
characteristic flow rate for an intermediate setting of the temperature selector according to 6.2.1.3.
Note 1 to entry: The nominal flow rate for thermostatic valves having a pre-setting facility is that obtained
when the pre-setting facility is inoperative.
3.4.3
maximum flow rate
q
m, max
maximum water flow rate that can be obtained at a differential pressure of 10 kPa (0,1 bar)
3.4.4
hysteresis
temperature difference between the opening and closing curves obtained at the same flow rate
Note 1 to entry: See Figure 9.
Note 2 to entry: If the opening and the closing curves cross each other the value of the hysteresis will be
measured at 1 K P-deviation.

Key
q flow rate a opening curve S temperature point S
m
°C water bath temperature b closing curve
 c theoretical curve
 d hysteresis
 e closing temperature
 f opening temperature
Figure 9 — Explanatory graph of characteristic curves
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3.4.5
differential pressure influence
difference between the temperature points S on the theoretical closing curves obtained at different
differential pressures
Note 1 to entry: See Figure 9.
3.4.6
influence of static pressure
temperature difference between two closing curves plotted at different static pressures at the same
flow rate
3.4.7
water temperature effect
difference in sensor temperatures which is equivalent to the flow rate deviation caused by a change of
temperature of the water flowing through the valve
3.4.8
influence of ambient temperature on thermostatic valves with transmission elements
temperature difference obtained at the same flow rate between two opening curves, one recorded with
and one without temperature difference between sensor and transmission unit
Note 1 to entry: Valves according to 3.2.2 to 3.2.4.
3.4.9
response time
time taken for a change of flow rate after a step-change of air temperature
Note 1 to entry: This change of flow rate corresponds to a pre-determined temperature difference in accordance
with 6.4.1.13.
3.5
technical definitions
3.5.1
sensor temperature
measured temperature of the sensor
Note 1 to entry: In the test it is the same as the temperature of the water bath.
3.5.2
differential pressure
Δp
difference of pressure between valve inlet and valve outlet
3.5.3
closing curve and opening curve
curves showing the functions of the water flow versus sensor temperature at constant differential
pressure when the valve is closing and opening respectively and at the same temperature selector
setting
Note  to entry: See Figure 9.
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3.5.4
closing temperature and opening temperature
sensor temperatures obtained from the closing and opening curves respectively for zero flow
Note 1 to entry: See Figure 9.
3.5.5
theoretical curve
straight line which passes through the points 0,5 q and 0,25 q on the characteristic curve
m s m s
Note 1 to entry: Construction shall be according to 6.2.2.
Note 2 to entry: See Figure 9.
3.5.6
temperature point S
point of intersection of the theoretical curve with the abscissa q = 0
m
Note 1 to entry: According to 6.2.2.
Note 2 to entry: See Figure 9.
4 Symbols and abbreviations
Table 1 — Symbols and abbreviations
Symbol Explanation Unit
q
Flow rate kg/h
m
qm,N Nominal flow rate kg/h
qm,s Characteristic flow rate kg/h
qm,max Maximum flow rate kg/h
q at maximum setting of the
m s
qm,s,max kg/h
temperature selector
q at minimum setting of the
m s
qm,s,min kg/h
temperature selector
q
m,x1 Auxiliary flow rates for measuring the
kg/h
response time
qm,x2
Sensor temperature which corresponds
t
°C
s
to the characteristic flow rate
t at maximum setting of the
s
ts,max °C
temperature selector
t at minimum setting of the
s
ts,min °C
temperature selector
S Temperature point °C
Δp Differential pressure Pa
K Temperature difference Kelvin
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5 Requirements
5.1 Dimensions
Dimensions and connection details for some types of radiator valves are given in Annex A.
5.2 Mechanical properties
5.2.1 Resistance to pressure, leak-tightness of the valve body assembly
During the test according to 6.3.1, there shall be no leak from the connections nor through the wall of
the body.
5.2.2 Leak-tightness of the stem seal
The stem seal shall show no leakage of air during the test according to 6.3.3.
5.2.3 Resistance of the valve body assembly to a bending moment
The valve shall withstand the load according to 6.3.4 without permanent functional impairment, and
shall fulfil the requirements of the subsequent tests.
Permanent deformation shall not be taken into account.
5.2.4 Resistance of the temperature selector to a torque
No damage or permanent deformation shall be visible after the test according to 6.3.5.
5.2.5 Resistance of the temperature selector to a bending moment
No damage or permanent deformation shall be visible after the test according to 6.3.6.
5.2.6 Exchange of the stem seal
It shall be possible to exchange the stem seal and/or the insert without draining the heating installation
in which the valve is mounted.
5.3 Operating characteristics
5.3.1 Nominal flow rate and flow rate at S-1
The nominal flow rate declared by the manufacturer shall not vary by more than 10 % for flow rates
> 33 kg/h and by more than 3 kg/h for flow rates ≤ 33 kg/h from the value determined in the test
specified in 6.4.1.1.
The plotted flow rate S -1 K shall not be more than 70 % of the nominal flow rate. For presettable
valves, the 70 % are only valid for the maximum pre-setting position.
5.3.2 Characteristic flow rate at the minimum and maximum setting of the temperature selector
This flow rate qm,s determined according to 6.4.1.5 shall be within the following ranges:
• at maximum setting: q ≥ 0,8q
m,s,max m,N;
• at minimum setting: 1,2q ≥ q ≥ 0,5q
m,N m,s,min m,N.
5.3.3 Characteristic flow rate for thermostatic valves having a pre-setting facility
For thermostatic valves having a pre-setting facility, the characteristic flow rate declared by the
manufacturer for an intermediate setting of the temperature selector according to 6.2.1.3 and for each
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specified pre-setting position shall not vary by more than the tolerance declared by the manufacturer
from the values determined in the test specified in 6.4.1.3.
5.3.4 Sensor temperature at the minimum and maximum setting of the temperature selector
This sensor temperature ts determined according to 6.4.1.6 shall be within the following range:
• 5 °C ≤ t ≤ 32 °C.
s
5.3.5 Hysteresis at the nominal flow rate
The hysteresis determined according to 6.4.1.7 shall not be greater than 1 K and not exceed the value
declared by the manufacturer by more than 0,2 K.
5.3.6 Differential pressure influence
The differential pressure influence determined according to 6.4.1.8 shall not be greater than 1 K and not
exceed the value declared by the manufacturer by more than 0,3 K.
If the measured value is negative (e.g. in case of opposite flow direction) it shall be documented as
absolute value.
5.3.7 Influence of the static pressure
The influence of the static pressure determined according to 6.4.1.9 shall not be greater than 1 K.
5.3.8 Temperature difference between temperature point S and the closing and opening
temperature respectively
The temperature difference between temperature point S and the closing and opening temperature
respectively determined according to 6.4.1.10 shall not be greater than 0,8 K.
5.3.9 Influence of ambient temperature on thermostatic valves with transmission elements
The influence of the ambient temperature determined according to 6.4.1.11 shall not be greater than
1,5 K.
5.3.10 Water temperature effect
The effect that is caused by a change of the temperature of the water flowing through the valve of 30 K
and which is determined according to 6.4.1.12 shall not be greater than:
• 1,5 K for thermostatic valves with the sensor incorporated according to 3.2.1;
• 0,75 K for thermostatic valves with the transmission elements according to 3.2.2 to 3.2.4
and not exceed the value declared by the manufacturer by more than 0,3 K.
5.3.11 Response time
The response time determined according to 6.4.1.13 shall not exceed 40 min and the value declared by
the manufacturer by more than 7 min.
5.4 Endurance and temperature resistance
5.4.1 Mechanical endurance
The values of the sensor temperatures at the nominal flow rate before and after the mechanical
endurance test according to 6.4.2.1 shall not vary by more than 2 K.
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The nominal flow rate determined after the mechanical endurance test shall not vary by more than
± 20 % from that determined before the endurance test.
5.4.2 Thermal endurance
The values of the sensor temperatures at nominal flow rate before and after the thermal endurance test
according to 6.4.2.2 shall not vary by more than 2 K.
The nominal flow rate determined after the thermal endurance test shall not vary by more than ± 20 %
from that determined before the endurance test.
5.4.3 Temperature resistance
The values of the sensor temperatures at nominal flow rate before and after the temperature resistance
test according to 6.4.2.3 shall not vary by more than 1,5 K.
The nominal flow rate determined after the temperature resistance test shall not vary by more than
± 20 % from that determined
...

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