各位同仁,这个测试具体怎么实施的能否帮忙解答一下,主要是c)项不理解
) c/ F* p3 ~4 N' ?; n) q M6 I4 F5 M17.31 Junction box rigidity
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) F% W. C# |+ J; |. s; e17.31.1 A junction box intended for pulling conductors shall be tested as follows:7 f7 G& K& |; k0 B
+ X: U% F0 v8 I! q3 J. |* f" pa) the luminaire shall be secured on a 12.7 mm (0.5 in) thick wood panel so that it is rigidly affixed to the panel, and the panel shall extend beyond the junction box;
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, t! R X' e: Yb) all junction box covers shall be removed;
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. h2 `$ Q! c2 ^+ d7 K; Nc) the weight specified in Table 17.31.1 shall be attached, by a wire or cord that does not contact any surface of the junction box, to a conduit fitting installed to the box so the force is applied from inside the junction box at the point most likely to result in deformation; and
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重量按照表17.31.1所示,[size=13.3333px]通过不接触接线盒任何表面的电线或软线连接到安装在接线盒上的导管接头上,以便在最可能导致变形的点从接线盒内部施加力。 这个力是怎么施加的?用的什么设备?不接触接线盒的表面是什么意思?
& ]! U3 o/ A! L d) after 2 min, the weights shall be removed and any permanent deformation from the original shall be measured.- {5 i8 X2 G: f9 @2 P
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