Using electron switch by BTA, BTA at touch off cross zero, thus deferent electron sine wave is intact.

用双向晶闸管作为电子开关，双向晶闸管过零触发，因而输出的是完整的正弦波。

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It should switch off the weld machine; the welding tongs should put on the insulator or hang on. Don't touch the member.

焊接完后及时关闭焊机，将焊钳放在绝缘物品上或悬挂起来，不得与构件接触。

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This paper is concentrated on brief introduction to the ON/OFF valve with no-touch approach switch. The contents include its advantages, system constitution, calibration, and its applications.

本文简要介绍了带无触点接近开关ON/OFF的优点，系统组成，调校及其应用情况。

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The screen can also be turned on and off using the switch, enabling one-touch operations.

ENGADGET: blogger-avatar

While Blackberries, pocket PCs and mobile phones have made it easier to stay in touch with the office, the danger is that workers find it difficult to switch off even when they are supposed to be away from the office.

CNN: Stressed out in the sunshine