| 摘要 |
<p>A safety circuit is utilized in a blow forward contact start plasma arc torch to extinguish the current to the torch upon determination of an unsafe operating condition. The torch includes a torch body, an electrode and a translatable conductive nozzle biased into contact with the electrode. The safety circuit receives a reference signal, a signal indicative of the arc voltage and a mode status signal. The torch current is extinguished when the signal indicative of the arc voltage is less than the reference signal and the mode status signal indicates the torch is operating in the transferred arc mode.</p> |
