1、 EIA STANDARD TP-04B Normal Force Test Procedure for Electrical Connectors EIA-364-04B (Revision of EIA-364-04A) August 2015 Electronic Components Industry Association EIA-364-04B ANSI/EIA-364-04B-2015 Approved: August 26, 2015 NOTICE EIA Engineering Standards and Publications are designed to serve
2、the public interest through eliminating misunderstandings between manufacturers and purchasers, facilitating interchangeability and improvement of products, and assisting the purchaser in selecting and obtaining with minimum delay the proper product for his particular need. Existence of such Standar
3、ds and Publications shall not in any respect preclude any member or nonmember of ECIA from manufacturing or selling products not conforming to such Standards and Publications, nor shall the existence of such Standards and Publications preclude their voluntary use by those other than ECIA members, wh
4、ether the standard is to be used either domestically or internationally. Standards and Publications are adopted by ECIA in accordance with the American National Standards Institute (ANSI) patent policy. By such action, ECIA does not assume any liability to any patent owner, nor does it assume any ob
5、ligation whatever to parties adopting the Standard or Publication. This EIA Standard is considered to have International Standardization implications, but the International Electrotechnical Commission activity has not progressed to the point where a valid comparison between the EIA Standard and the
6、IEC document can be made. This Standard does not purport to address all safety problems associated with its use or all applicable regulatory requirements. It is the responsibility of the user of this Standard to establish appropriate safety and health practices and to determine the applicability of
7、regulatory limitations before its use. (From Standards Proposal No. 5345.02 formulated under the cognizance of the CE-2.0 Committee on EIA National Connector and Sockets Standards.) Published by Electronic Components Industry Association 2015 EIA Standards see figure 1. 2.1.1.3.1.2 The tip of the te
8、st probe shall be either flat or curved. If a flat tip is used, the width of the flat shall be 0.127 millimeter (0.005 inch) minimum but shall not exceed the width (W) of the contact tine. If curved, the radius shall be equal to or less than the internal radius of the tine; see figures 1 and 2). 2.1
9、.1.3.2 Flat, concave, dimpled or crowned contacts The test probe mating surface shall be flat with a width not to be less than 75% of the total width of the contact element being tested; see figure 3). 2.1.1.3.2.1 The length of the test probe contacting surface shall be of sufficient length to avoid
10、 improper interference and shall maintain proper contact with the test sample during the deflection cycle. 2.1.1.3.2.2 The test probe contacting surface shall be polished and free of ridges, tool marks or burrs. 2.1.1.3.2.3 The test probe shall be axially positioned relative to the contact element t
11、o be tested so as not to cause eccentric or torsional loading of the beam beyond that which may be normal to its operational mode. 2.1.1.4 A linear transducer shall be used for determining the distance deflected with a non-linearity of 1%. 2.1.1.5 An X-Y recording instrument shall be used with a cap
12、ability of recording with a precision of 1%. 2.1.1.6 When a force readout instrument is used, it shall be capable of reading the force to an accuracy of 2%. 2.1.1.7 The equipment shall be so arranged to allow the contact to be deflected manually or through a driving mechanism to predetermined levels
13、 as required. The equipment shall be capable of producing a smooth axial displacement at a controlled rate between 0.254 mm and 25.4 mm (0.01 inch and 1.0 inch) per minute 2.1.1.3.1 Convex contacts (split cylinder) EIA-364-04B Page 3 2.1.1.8 Due to various connector configurations and contact design
14、s, different fixturing techniques may be required. Some designs allow individual contacts to float within the connector housing or the deflecting elements may be contained internal to an outer contact shell. It may be necessary to remove these contacts from the connector housing for testing. Special
15、 fixturing techniques or instructions for “loose” contact testing shall be indicated in the referencing document. 2.1.2 Test method B 2.1.2.1 Normal force gage similar in geometry to the mating part and capable of measuring the normal force without altering the working contact interface characterist
16、ics. The gage shall provide a linear output with relative indifference to the position of the load within an accuracy of 1.5%. 2.1.2.2 Force readout instrument capable of reading the force to an accuracy of .5%. 2.1.2.3 Weights certified within the range of normal force values being measured. 2.1.2.
17、4 Calibration fixture capable of positioning the certified weights on the center of the normal force gage sensing beam. 3 Test specimen 3.1 Description Test specimen shall consist of contacts or connector assemblies. 3.2 Preparation 3.2.1 Contacts or connector assemblies shall be prepared prior to p
18、lacement in the housing fixture. 3.2.1.1 In the case of connector assemblies, housings may be modified if access is not possible and normal force characteristics are not affected. The natural locking and preload features of the contact/housing system shall not be disturbed. 3.2.1.2 In the case of mu
19、ltiple tine contacts, all tines not to be tested which may interfere with the test probes, shall be removed if the tine to be tested is not affected. 3.2.1.3 Connector assemblies which are normally soldered to printed circuit boards or held in place thereof shall be tested in that state. 3.2.2 Conta
20、cts or connector assemblies as prepared shall be placed in the holding fixture. 3.2.2.1 Placement of connector assemblies in the fixture shall be accomplished so as not to disturb the natural connector locking features, position of the contact relative to its housing, or modify the natural beam defl
21、ection characteristics. EIA-364-04B Page 4 3.2.2.2 Placement of loose contacts in the fixture shall be accomplished by having said fixture grip the contact in the area which is normally fixed in the application without modifying the natural beam deflection characteristics. 4 Test procedure 4.1 Test
22、method A Unless otherwise specified, the following procedures shall be utilized in the determination of permanent set when required. 4.1.1 Normal force/deflection characteristics 4.1.1.1 It is recommended that the normal force/deflection characteristics for contacts tested be plotted on the same gra
23、ph with appropriate identification. 4.1.1.2 Unless otherwise specified, the graphics shall indicate the deflection on the horizontal axis and normal force on the vertical axis; see figure 4. 4.1.1.3 Applicable measuring equipment shall be calibrated (i.e. load cell, displacement devices and X-Y reco
24、rder). 4.1.1.4 Measure contact gap to determine the amount of deflection required to attain the contact normal force for minimum, nominal and maximum mating elements. 4.1.1.5 The contact, connector assembly or test probe shall be moved until it registers a force not to exceed 0.03 Newton (formerly s
25、pecified as 3.0 grams) or establishes a zero reference point. 4.1.1.6 The test probe shall be attached to the measuring equipment in a manner which shall allow the contact beam to deflect in the same direction as caused by the mating element. 4.1.1.7 The test unit shall then be moved to deflect the
26、contact the specified distance recording the normal force generated or plotting the force/deflection characteristic. 4.1.2 Permanent Set Determination - Direct Plotting Technique 4.1.2.1 The deflection level at which permanent set is to be determined shall be established. 4.1.2.2 The normal force/de
27、flection characteristic shall be directly plotted in accordance with the procedure as described in 4.1.1.6 to 4.1.1.7 to the specified deflection level. EIA-364-04B Page 5 4.1.2.3 The contact shall be unloaded until the original zero point is reached. 4.1.2.4 Starting from the original zero point (s
28、ee 4.1.1.5), the contact shall be redeflected to the point established in 4.1.1.7, and unloaded ten additional times or until the unloading curve is superimposed on the unloading curve from the previous cycle (indicating no additional set is occurring), whichever occurs first. 4.1.2.5 The incrementa
29、l change in the zero point establishes the magnitude of permanent set occurring if any, see figure 5. 4.1.3 Permanent Set Determination - Non-plotting Technique 4.1.3.1 The deflection level at which permanent set is to be determined shall be established. The zero reference point as established shall
30、 be recorded. 4.1.3.2 The contact shall be deflected to the specified deflection level in accordance with the procedure as described in 4.1.1.6 to 4.1.1.7, except that the normal force does not have to be recorded. 4.1.3.3 The contact shall be unloaded until a zero load is reached. 4.1.3.4 The proce
31、dure in accordance with 4.1.3.2 and 4.1.3.3 shall be repeated for a total of 10 deflection cycles. 4.1.3.5 After the 10th cycle, the zero reference point shall be re-established and recorded. 4.1.3.6 The difference between the initial and final reference readings establishes the magnitude of permane
32、nt set occurring, if any. 4.2 Test method B 4.2.1 Calibrate normal force gage with the force readout instrument using appropriate calibration fixture and certified weights. 4.2.2 Normal force measurements are made by inserting the normal force gage into the connector housing or “loose” contact, posi
33、tioning the center of the gage sensing beam at the contact interface; see figure 6. Normal force is read directly from the force readout instrument. Care shall be taken so that external forces do not affect the measurement. 4.2.3 Normal forces for minimum, nominal, and maximum mating pin sizes can b
34、e measured by using representative gage sizes. 4.2.8 Unless otherwise specified, the following procedure shall be utilized in determining the change in normal force due to permanent set. 4.2.8.1 Measure the normal force of the contact using a minimum size normal force gage. EIA-364-04B Page 6 4.2.8.
35、2 Measure the normal force of the contact using a maximum size normal force gage. 4.2.8.3 Insert a maximum size pin or blade gage, depending on sample configuration, into the contact and repeat the action for 10 cycles. 4.2.8.4 Re-measure the normal force of the contact; first with a minimum size no
36、rmal force gage and then with a maximum size normal force gage. 4.2.8.5 The difference between the initial and final minimum size gage readings dictates the change in normal force due to permanent set. 5 Details to be specified The following details shall be specified in the referencing document: 5.
37、1 Test procedure 5.2 Test method (test method A shall be used if not specified in the referencing document) 5.3 Number of contacts to be tested and location 5.4 Contacts tested in housing or loose piece. 5.5 Test method A 5.5.1 Deflection level to be applied to determine normal force and/or permanen
38、t set 5.5.2 Requirements including deflection probe direction if required 5.5.3 Holding technique to be used, special conditions and/or instructions as required 5.5.4 Rate of deflection 5.6 Test method B 5.6.1 The contact receptacle and pin dimensions. 5.6.2 The contact configuration; twin beam, box
39、, single beam etc. 5.6.3 If housed, the distance from the face of the contact to the contact interface; and from the interface to the bottoming out point of the mating element. 5.6.4 Expected normal force range EIA-364-04B Page 7 6 Test documentation Documentation shall contain the details specified
40、 in clause 5 (when provided), and the following: 6.1 Title of test 6.2 Specimen description and identification, including fixture if applicable 6.3 Test equipment used including gage identification and dimensions as applicable, and date of last and next calibration 6.4 Name of operator and date of t
41、est 6.5 Data sheets and/or plots shall contain the following information: 6.6 Connector and/or contact part number or description 6.7 Normal force at the specified deflection level (Method A (may be shown graphically on plotted data) or at specified gage size (Method B) and other required observatio
42、ns 6.8 Holding technique as described herein, special fixtures used or special instructions Figure 1 - Test probe configuration W Direction of applied force Acceptable Unacceptable EIA-364-04B Page 8 Figure 2 - Test probe tip Figure 3 - Test probe mating surface Figure 4 - Deflective versus normal f
43、orce curve Contact ContactProbe Probe Force applicationForce applicationFlat Dimpledor CrownedConcave Deflection Normal force Flat 0.127 millimeter (0.005 inch) minimum but not greater than the width (W) of the contact tine, see figure 1. orEqual to or less than internal radius EIA-364-04B Page 9 Fi
44、gure 5 - Permanent set deflection versus normal force curve Figure 6 Normal force gage position Normal force Final unload Permanent set deflection Initial loadSensing elements Pin Normal force gageSensing elements centered at contact interface Receptacle beams EIA-364-04B Page A-1 Annex A Informativ
45、e A.1 Normal force is indicative of withdrawal force. However, withdrawal force is a function of normal force, cleanliness of the mating surfaces, surface roughness, surface hardness, coefficient of friction of the materials in contact, etc. As, such, withdrawal forces may vary within a given design
46、 without affecting normal force. A.2 Depending upon the equipment used in conjunction with the test setup conditions, correction factors may be required to assure proper deflection levels are adhered to and in determining permanent set. ECIA Document Improvement Proposal If in the review or use of t
47、his document, a potential change is made evident for safety, health or technical reasons, please fill in the appropriate information below and mail or FAX to: Electronic Components Industry Association EIA Standards & Technology Department 2214 Rock Hill Rd., Suite 265 Herndon, VA 20170 FAX: (571-32
48、3-0245) Document No.: Document Title: Submitters Name: Telephone No.: FAX No.: e-mail: Address: Urgency of Change: Immediate: At next revision: Problem Area: a. Clause Number and /or Drawing: b. Recommended Changes: c. Reason/Rationale for Recommendation: Additional Remarks: Signature: Date: FOR ECI
49、A USE ONLY Responsible Committee: Chairman: Date comments forwarded to Committee Chairman: Revision History Revision letter Project number Publication date Additions, changes and deletions - SP-1838 March 1987 Initial publication A SP-4874-A March 2002 B SP-5345.02 Removed * from table and deleted * note under table 1 Revised paragraph 2.1.1.3.1.2 Changed “Detail Specification” to “ referencing document” in paragraph 2.1.1.8 Revised text under paragraph 6 Revised figure 1 and 2 and include the “W” dimension. Electronic Components Industry Association 2214 Rock Hill Road, Suit
