1、March 2015DEUTSCHE NORM English price group 9No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 27.060.30!%LR“2414761w
2、ww.din.deDIN 4754-2Heat transfer installations working with organic heat transfer fluids Part 2: Draught diverter,English translation of DIN 4754-2:2015-03Wrmebertragungsanlagen mit organischen Wrmetrgern Teil 2: Strmungssicherungen,Englische bersetzung von DIN 4754-2:2015-03Installations de transfe
3、rt de chaleur aux fluides caloporteurs organiques Partie 2: Coupetirages,Traduction anglaise de DIN 4754-2:2015-03SupersedesDIN 32727:198102, withdrawn 200709See start of applicationwww.beuth.deDocument comprises 15 pagesDDIN-Normenausschuss Heiz- und Raumlufttechnik sowie deren Sicherheit (NHRS)DIN
4、-Sprachendienst11.16DIN 4754-2:2015-03 2 A comma is used as the decimal marker. Start of application The start of application of this standard is 2015-03-01. For DIN 32727:1981-02 there is no transition period as the standard was withdrawn in 2007-09. DIN 4754-2:2015-03 3 Contents Page Foreword 4 In
5、troduction 5 1 Scope . 6 2 Normative references . 6 3 Terms and definitions 6 4 Safety requirements . 7 4.1 Materials, rating . 7 4.2 Electrical safety 7 4.3 Design . 8 5 Testing . 11 5.1 Test objects and test documents 11 5.2 Test medium 12 5.3 Inspecting the design and test documents . 12 5.4 Test
6、ing the leak-tightness 12 5.5 Utilization test . 12 5.6 Minimum volume flow rate 13 6 Marking . 13 Annex A (informative) Test types . 14 Bibliography . 15 DIN 4754-2:2015-03 4 Foreword This standard includes safety requirements in Clause 4. This document has been prepared by DIN-Normenausschuss Heiz
7、- und Raumlufttechnik (DIN Standards Committee Heating and Ventilation), Working Committee NA 041-01-41 AA Wrmebertragungsanlagen. DIN 4754, Heat transfer installations working with organic heat transfer fluids consists of the following parts: Part 1: Safety requirements, test Part 2: Draught divert
8、er Part 3: Level controller Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. DIN shall not be held responsible for identifying any or all such patent rights. In addition to the legal units of measurement, this standard also uses th
9、e unit “bar”. It should, however, be noted that according to the German law on units in metrology, the use of these units is not permitted in official or business communications within Germany. Conversion: Unit not permitted Unit permitted Conversion bar Pa 1 bar = 105Pa Amendments The standard diff
10、ers from DIN 32727:1981-02, which was withdrawn in 2007-09, as follows: a) Subclauses 1.2 and 1.3 have been deleted; b) Subclause 4.2.4.3 “Magnetic transmission” has been deleted; c) Subclause 5.5.2 “Additional test for devices with magnetic transmission” has been deleted; d) Subclause 4.2 “Electric
11、al safety” has been added; e) Subclause 5.2 “Test types” has been moved to informative Annex A; f) the standard has been editorially revised. Previous versions DIN 32727: 1981-02 DIN 4754-2:2015-03 5 Introduction The purpose of this standard is to determine certain fundamental requirements with resp
12、ect to the technical design and testing of draught diverters in heat transfer installations working with organic heat transfer fluids. The tests and test methods described in this standard may also be applied to type and acceptance tests if required. The revision of DIN 4754:1994-09 also made a revi
13、sion of DIN 32727:1981-02 necessary. This revision process incorporated knowledge and experience concerning draught diverters with the state of the art and also took current legal provisions into consideration. DIN 4754-2:2015-03 6 1 Scope This standard applies to draught diverters in heat transfer
14、installations working with organic heat transfer fluids according to DIN 4754-1 and specifies minimum requirements with respect to the technical design and testing of draught diverters. 2 Normative references The following documents, in whole or in part, are normatively referenced in this document a
15、nd 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. DIN 4754-1:2015-03, Heat transfer installations working with organic heat transfer fluids Part 1:
16、Safety requirements, test E DIN EN 50156-1 (VDE 0116-1):2013-05, Electrical equipment for furnaces and ancillary equipment Part 1: Requirements for application design and installation DIN EN 60529 (VDE 0470-1), Degrees of protection provided by enclosures (IP-Code) DIN EN 61010-1, (VDE 0411-1):2011-
17、07, Safety requirements for electrical equipment for measurement, control and laboratory use Part 1: General requirements DIN EN 60730-2-6 (VDE 0631-2-6):2009-04, Automatic electrical regulation and control units for household and similar use Part 2-6: Particular requirements for automatic electrica
18、l pressure sensing regulation and control units including mechanical requirements DIN EN 61058-1 (VDE 0630-1), Switches for appliances Part 1: General requirements DIN EN ISO 5167-1, Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits runni
19、ng full Part 1: General principles and requirements VDI/VDE 20411), Measurement of fluid flow with primary devices Orifice plates and nozzles for special applications VDI/VDE 3512 Sheet 11), Temperature measurement for building automation Basic principles 3 Terms and definitions For the purposes of
20、this document, the terms and definitions given in DIN 4754-1 and the following apply. 3.1 draught diverter device that automatically switches off and locks the heating if the flow rate falls below the minimum volume flow rate in the heat transfer installation Note 1 to entry: The draught diverter ma
21、y contain and/or actuate display devices. Note 2 to entry: In the following, the draught diverter is also referred to as “the device”. 1)Obtainable from: www.vdi.de DIN 4754-2:2015-03 7 3.2 measuring element part of the draught diverter which receives the fluid and generates a measured value equival
22、ent to the volume flow rate 3.3 measured value transmission device that transfers the measured value to the evaluation unit 3.4 evaluation unit assembly that converts the measured value corresponding to the volume flow rate generated by the measuring element into an electrical output signal 3.5 swit
23、ching points of the evaluation unit 3.5.1 first switching point volume flow rate at which the heating is released in the small-load position during a cold start Note 1 to entry: See also: DIN 4754-1:2015-03, 4.3.12.5, Clause 3 3.5.2 second switching point minimum volume flow at which the heating is
24、switched off 4 Safety requirements 4.1 Materials, rating The quality of the materials as well as the form and rating of the components shall ensure that the devices are permanently safe and operational for a reasonable period upon correct installation and under the conditions indicated by the manufa
25、cturer for operation, maintenance and adjustment and the associated mechanical, chemical and thermal loads. The enclosures through which the thermal transfer fluid flows during operation shall be in accordance with the material requirements of DIN 4754-1; all parts receiving the heat transfer fluid
26、shall be designed for at least PN 16. Materials that lead to chemical reactions with the heat transfer fluid shall not be used. Tests shall be conducted according to 5.3 and 5.6. 4.2 Electrical safety Electrical components are subject to the requirements according to DIN EN 61010-1 (VDE 0411-1); the
27、 fault exclusions according to E DIN EN 50156-1 (VDE 0116-1):2013-05, 10.5.5.3.1 to 10.5.5.3.6 have overriding application. In deviation from Table 1, the relevant requirements in accordance with DIN EN 60730-2-6 (VDE 0631-2-6) shall be applied for devices with differential pressure sensors and tran
28、sducers. DIN 4754-2:2015-03 8 Table 1 Safety-relevant requirements for electrical devices Requirement Reference to clauses of DIN EN 61010-1 (VDE 0411-1):2011-07 for devices that are only used in industrial applications Protection against electric shock 6 Protective earth connection 6 Terminals and
29、connections 6.10 Setup 6.9 Resistance to moisture and dust 11.6 Dielectric strength and insulation resistance 6.8 Heating 10 Environmental loads 10.5 Mechanical strength 8 Threaded parts and joints Creepage distances and air gaps, insulation gaps 6.7 Heat and fire resistance, tracking resistance 9,
30、10 Individual parts 14 Improper use 6.5 4.3 Design 4.3.1 Leak-tightness 4.3.1.1 Leak-tightness of the measuring element If the measuring element is located in an enclosure (e.g. measuring chamber), this element, and the sealing parts, shall be leak-tight outwards so that, at most, an oil film result
31、s on the outer surface which does not cause any drop formation within 24 h under the allowable pressure and temperature loads nor when cold. If metal bellows or a similar component are used as a sealing element, this is permissible if a signal shift to the safe side occurs and oil escape is prevente
32、d if the element breaks. NOTE This requirement exists because additional influences that were not previously discernible can occur when installing a draught diverter in the system. A test shall be conducted according to 5.4. If the measuring element is located directly in the pipe (e.g. between two
33、flanges), the check for leak-tightness shall then be carried out as part of the testing of the heat transfer installation. DIN 4754-2:2015-03 9 4.3.1.2 Leak-tightness of the evaluation unit Due to the high working temperature at the measuring element, the evaluation unit is operated at a distance fr
34、om the measuring element. Temperature loads according to 4.3.2 apply for the evaluation unit. The test for the leak-tightness of the evaluation unit is conducted in accordance with DIN EN 60730-2-6 (VDE 0631-2-6):2009-04, Clause 18 insofar as applicable. Tests shall be conducted according to 5.3 and
35、 5.6. 4.3.2 Technical design requirements 4.3.2.1 Evaluation unit The evaluation unit shall satisfy at least degree of protection IP 44 according to DIN EN 60529 (VDE 0470-1) and withstand the resulting 70 C ambient temperature in the enclosure of the evaluation unit. The mechanical parts of the eva
36、luation unit shall be mounted with low-friction bearings. The mechanical output contacts shall exhibit transient characteristics, as defined in DIN EN 61058-1 (VDE 0630-1). Mercury switching tubes, Reed relays and Reed contacts are not permissible. Adjustment of the switching point(s) shall only be
37、possible using tools. The unlocking device can be either mounted on the device or embedded in the downstream electric circuit. Testing shall be according to 5.3. 4.3.2.2 Measuring element Any mechanically moving or guided parts shall be prevented from jamming. The manufacturer shall determine the me
38、asured value equivalent to the volume flow rate for the measuring element. The volume flow rate measurements can be omitted for measuring throttles that are calculated and designed according to DIN EN ISO 5167-1. Testing shall be according to 5.3 and 5.6. 4.3.3 Measured value transmission 4.3.3.1 Me
39、chanical transmission The mechanical transmission shall work with as little friction as possible and shall not cause any impermissible change in the frictional forces. Devices with a manually readjustable stuffing box do not fulfil these requirements. Moving bushings and sealing elements shall be ca
40、lculated and designed for at least 100 000 work cycles at maximum stroke, maximum allowable pressure pSand maximum allowable fluid temperature. The functional sequence shall be designed to ensure safety if the transmission elements fail. In the event of damage to the sealing elements, a possible esc
41、ape of the fluid shall be taken into consideration. It shall not be possible to block the transmission elements. Testing shall be according to 5.3.1 and 5.5. DIN 4754-2:2015-03 10 4.3.3.2 Electric transmission The transmission shall be such that a drop below the minimum volume flow rate level is sim
42、ulated both upon failure of the measuring signal as well as in the event of a short-circuit or an interruption in the evaluation unit. The evaluation unit shall be protected against effects from outside that can simulate a measuring signal. Testing shall be according to 5.3, 5.3.1 and 5.6. 4.3.3.3 H
43、ydraulic transmission Differential pressure pipes shall be made from steel. Their clear width shall not be less than 4 mm. If tubes are used, their joints shall be welded, hard-soldered or bolted with metallic sealing elements. Ducts and bores in differential pressure sensors shall exhibit a clear w
44、idth of minimum 3 mm. Testing shall be according to 5.3 and 5.6. 4.3.4 Differential pressure devices 4.3.4.1 The measuring setup shall be in accordance with Figure 1 or according to VDI/VDE 3512 Sheet 1. Where a setup according to VDI/VDE 3512 Sheet 1 with block valves is used, it shall be ensured t
45、hat the differential pressure line between the block valve and the differential pressure sensor forming part of the evaluation unit is at least 500 mm long. Testing shall be according to 5.3. Figure 1 Measuring setup Key 1 Differential pressure sensor (evaluation unit) 2 Block valve 3 Differential p
46、ressure transducer (measuring element) 4.3.4.2 Differential pressure transducers according to DIN EN ISO 5167-1, VDI/VDE 2041 and other design types may be used as measuring elements. The interrelation between differential pressure and volume flow rate shall be verified for design types not based on
47、 standardized calculation principles. Testing shall be according to 5.3 and 5.6. DIN 4754-2:2015-03 11 4.3.4.3 Shut-off valves in differential pressure pipes shall only be actuated using tools. Threaded joints in these pipes shall be designed so that they remain leak-tight without the use of sealing
48、 agents. Testing shall be according to 5.3. 4.3.4.4 Differential pressure pipes shall be rated in their clear diameter and in their length so that the response time of the device is not more than 5 s when the pipe is cold ( 20 C). The differential pressure pipe shall be in accordance with 4.3.3.3 “H
49、ydraulic transmission”. The extended length shall be at least 500 mm so that an adequate temperature reduction is attained. Testing shall be according to 5.3. 4.3.5 Other devices The requirements of Clause 4 apply by analogy. Testing shall be according to 5.3 to 5.6. 5 Testing 5.1 Test objects and test documents 5.1.1 Test objects For the type testing, the manufacturer shall provide the test body with a complete test device, which shall undergo the following tests. Display devices and display units are not tested. 5.1.2 Test documents The f
