1、Designation: F2072 01 (Reapproved 2007)F2072 14Standard Practice Test Method forHosedown of a Membrane Switch1This standard is issued under the fixed designation F2072; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of la
2、st revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice establishes procedures for the hosedown of a membrane switch to verify adequate protection from ingress of
3、water from a high-volume water spray.1.2 This practice can also be used to verify the ability of a membrane switch or graphics layer to act as a liquid seal for a finishedproduct.1.3 Additional test methods or practices can be incorporated to investigate specific results or capabilities.1.4 This pra
4、ctice is a modification of NEMA Publication Number 250-1991 Section 6.7 which is a test for hosedown of afinished product housing.2. Referenced Documents2.1 NEMA Publication 250-199123. Terminology3.1 Definitions:3.1.1 membrane switch, na momentary switching device in which at least one contact is o
5、n, or made of, a flexible substrate.3.1.2 specified resistance, nmaximum allowable resistance as measured between two terminations whose internal switchcontacts, when held closed, complete a circuit.4. Significance and Use4.1 The presence of water inside a membrane switch can affect its mechanical o
6、peration or electrical functionality, or both.4.2 This practice establishes a procedure to verify the ability of a membrane switch to resist the entry of liquid into itself or afinished product, or both. It is useful in identifying design deficiencies.4.3 Hosedown testing may be destructive, therefo
7、re any samples tested should be considered unfit for future use.5. Interferences5.1 External VentingAny deliberate external venting of the switch will allow liquid to enter.5.2 Atmospheric PressureSignificant changes in atmospheric pressure during the test or at different facilities may alter thetim
8、e in which leakage might occur.5.3 Duration of TestLonger exposure time increases the possibility of leakage.5.4 Dye ColoringChoose a dye coloring that will not chemically attack the materials.6. Apparatus6.1 Water Supply, capable of delivering a stream of water at a rate of at least 65 gal/min thro
9、ugh a 1 in. (25 mm) internaldiameter nozzle for the specified duration,6.2 An appropriate device or fixture to hold the switch in a fixed position,1 This practice test method is under the jurisdiction of ASTM Committee F01 on Electronics and is the direct responsibility of Subcommittee F01.18 on Mem
10、braneSwitches.Current edition approved Feb. 1, 2007Jan. 1, 2014. Published March 2007January 2014. Originally approved in 2000. Last previous edition approved in 20012007 asF2072F207201(2007).01. DOI: 10.1520/F2072-01R07.10.1520/F2072-14.2 For referencedASTM standards, visit theASTM website, www.ast
11、m.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what ch
12、anges have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the off
13、icial document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16.3 Any additional equipment as required by other test methods employed, and6.4 Nozzle with 1 in. (25 mm) internal diameter.7. Test Specimen7.1 The test specimen will be a
14、 membrane switch with or without graphics laminated to a rigid material or the final intendedmounting configuration (using a clear material will facilitate visual inspection).8. Conditioning8.1 Condition specimens by exposure to ambient conditions for 72 h prior to hosedown to allow full cure of adh
15、esives.9. Procedure9.1 Pre-Test Setup:9.1.1 Fixture Unit Under Test (UUT) as specified.9.2 In-Process Test:9.2.1 Test switch for proper function if required.9.2.2 Direct water flow at test specimen at all angles of potential water entry such as seams, joints, external operatingmechanisms, etc. from
16、a distance of 10 to 12 ft (3.0 to 3.5 m) for a total of 5 min or as specified.9.2.3 Test switch for proper function if required.9.2.4 Perform visual inspection to determine if liquid has penetrated the UUT.10. Report10.1 Report the following information:10.1.1 Duration of test,10.1.2 Physical/Aesthe
17、tic changes, and10.1.3 Functional test data, if required.11. Keywords11.1 hose down; membrane switch; water sprayASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advi
18、sed that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either
19、reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If
20、you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individu
21、al reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from
22、 the ASTM website (www.astm.org/COPYRIGHT/).1. Scope1.1 This test method establishes procedures for the hosedown of a membrane switch to verify adequate protection from ingressof water from a high-volume water spray.1.2 This test method can also be used to verify the ability of a membrane switch or
23、graphics layer to act as a liquid seal for afinished product.1.3 Additional test methods or practices can be incorporated to investigate specific results or capabilities.1.4 This test method is a modification of NEMA Publication Number 250-2008 Section 6.7 which is a test for hosedown of afinished p
24、roduct housing.2. Referenced Documents2.1 ASTM Standards:2F1595 Practice for Viewing Conditions for Visual Inspection of Membrane SwitchesF1680 Test Method for Determining Circuit Resistance of a Membrane SwitchF1689 Test Method for Determining the Insulation Resistance of a Membrane SwitchF2072 142
25、2.2 NEMA Publication:250-2008 33. Terminology3.1 Symbols:3.1.1 membrane switch, na momentary switching device in which at least one contact is on, or made of, a flexible substrate.3.1.2 specified resistance, nmaximum allowable resistance as measured between two terminations whose internal switchcont
26、acts, when held closed, complete a circuit.4. Significance and Use4.1 The presence of water inside a membrane switch can affect its mechanical operation or electrical functionality, or both.4.2 This practice establishes a procedure to verify the ability of a membrane switch to resist the entry of li
27、quid into itself or afinished product, or both. It is useful in identifying design deficiencies.4.3 Hosedown testing may be destructive, therefore any samples tested should be considered unfit for future use.5. Interferences5.1 External Venting Any deliberate external venting of the switch will allo
28、w liquid to enter.5.2 Atmospheric PressureSignificant changes in atmospheric pressure during the test or at different facilities may alter thetime in which leakage might occur.5.3 Duration of Test Longer exposure time increases the possibility of leakage.5.4 Dye ColoringChoose a dye coloring that wi
29、ll not chemically attack the materials.6. Apparatus6.1 Water Supply, capable of delivering a stream of water at a rate of at least 65 gal/min through a 1 in. (25 mm) internaldiameter nozzle for the specified duration,6.2 An appropriate device or fixture to hold the switch in a fixed position,6.3 Any
30、 additional equipment as required by other test methods employed, and6.4 Nozzle with 1 in. (25 mm) internal diameter.7. Test Specimen7.1 The test specimen will be a membrane switch with or without graphics laminated to a rigid material or the final intendedmounting configuration (using a clear mater
31、ial will facilitate visual inspection).8. Conditioning8.1 Condition specimens by exposure to ambient conditions for 72 h prior to hosedown to allow full cure of adhesives.9. Procedure9.1 Pre-Test Setup:9.1.1 Fixture Unit Under Test (UUT) as specified.9.2 In-Process Test:9.2.1 Test switch for proper
32、function if required.9.2.1.1 Visually inspect in accordance with Practice F1595 and note anything that could affect results or of interest to compareafter test. Pictures of UUT may be useful as well but not required.9.2.1.2 Measure circuit resistance in accordance with Test Method F1680 of preselect
33、ed (or all switches).9.2.1.3 Measure insulation resistance in accordance with Test Method F1689 of preselected (or all) conductive points.9.2.2 Direct water flow at test specimen at all angles of potential water entry such as seams, joints, external operatingmechanisms, etc. from a distance of 10 to
34、 12 ft (3.0 to 3.5 m) for a total of 5 min or as specified.9.2.3 Measure and observe the characteristics of the switch as in 9.2.1 and if liquid has penetrated the UUT record as muchdetail as possible the extent of penetration seen by visual inspection. Pictures of UUT may be useful as well but not
35、required.10. Report10.1 Report the following information:10.1.1 Duration of test,3 National Electrical Manufacturers Association (NEMA), 1300 North 17th Street, Suite 1847, Rosslyn, VA 22209.F2072 14310.1.2 Physical/Aesthetic Changes:10.1.2.1 Visual inspection description.10.1.2.2 Liquid penetration
36、 description.10.1.2.3 Pictures of UUT (if available).10.1.3 Electrical Characteristic Changes:10.1.3.1 Circuit resistance (Test Method F1680).10.1.3.2 Insulation resistance (Test Method F1689).10.1.4 Water temperature.10.1.5 Atmospheric pressure.10.1.6 Method of mechanically conditioning, if any.11.
37、 Keywords11.1 hose down; membrane switch; water sprayASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent ri
38、ghts, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn.Your comments are invited either for
39、 revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing
40、 you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).F2072 144
