问几个关于AS/NZS 3112插座的标准理解问题

孟云房

广东安规检测
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小型摆管淋雨试验机

IPX5X6X7喷水试验机

1000L恒温恒湿箱

各种试验指现货

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水平垂直燃烧机

自动卷线器试验机

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IEC61347/UL935镇流器热试验箱

灯具防风罩

IK冲击试验机

UL498插头插座量规

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稳定性试验台

家电温升测试角

针焰试验机现货

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家电125mm试验指

E12灯头量规

无绳壶无绳电熨斗插拔寿命试验机

IEC60335试验指甲

各位达人：

3.3.2 *******For socket-outlets intended to accommodate plugs with flat pins, contact shall be made with both sides of each pin, except that it shall be permissible to use spring-assisted single-sided contacts. These contacts shall not rely exclusively on the resilience of the contact material
and shall have an opposite face of material other than thermoplastic or resilient insulating
9 D- T+ m; W5 m% ematerial.

我的理解，打算插合扁插销插头的插座，应与插销双边接触，但允许弹簧辅助的单边插套。后面These contacts shall not rely exclusively on the resilience of the contact material
and shall have an opposite face of material other than thermoplastic or resilient insulating
material. 怎么理解的？these contact 是指所有插套，还是单边插套？不能仅仅依靠插套材料？？？

$ S5 t: c! z  y& [0 g* Z1 DIn socket-outlets designed for use with plugs complying with Figure 2.1, the contacts shall
be self-adjusting in pitch and contact-making
pitch是什么意思？
2 g9 @7 V( w7 t6 v4 m  n$ C
  q% h4 u; w$ z. A4 t0 |  v" D$ x0 X3.3.3  Within the socket-outlet, there shall be provision for effective guidance of the
corresponding plug pins to ensure direct entry and withdrawal without critical distortion of
7 Y3 f7 v% t% k7 R8 n2 W1 rthe socket-outlet contacts.
  h$ b1 F2 V- _( [! U5 E2 Y; f8 ^4 W0 ~这个条款是在讲插孔的前导孔吗？
3 K  z  W% e9 ?, S4 }& O; f- S
4 B  C9 M; \( `" \
另外，象3.1.1和3.3.1对端子和插套材料只给出了一句笼统的概括，实际检测和生产中，一般使用哪些材料算合格？是参考插头部分对端子和插销材料的规定吗？