A knife switch with iron shell shall be installed in the power supply line, which is exclusively for this oven, and the outer plate shall be grounded.

应在供电线路中安装铁壳闸刀开关一只，供此箱专用，并将外壳接地。

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The problem was soluted by the production line of automatic selection being composed of optical sensor , encoder, roller, plate turnover machine, steel shelf, approach switch.

通过运用由光电传感器、编码器、运输辊道、翻板机、过钢台架、接近开关组成的钢管自动分选生产线，可较好的解决这一问题。

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Then an electrical technician, Cassagnes came upon the Etch A Sketch idea in the late 1950s when he peeled a translucent decal from a light switch plate and found pencil mark images transferred to the opposite face, the Toy Industry Association said.

NPR: Inventor Of Etch A Sketch Dies In France At 86