| 摘要 |
<p>PURPOSE:To protect a drive system circuit, a welding head and an article to be welded. CONSTITUTION:When a line 30a or 30b is disconnected, an OR circuit 24 outputs a signal FB. When the lines 30a, 30b are connected reversely and an output from an amplifier 25 is made larger than voltage Vref1, a comparator 26 outputs a signal FR. When the conditions of welding are not stabilized and an output from a differential amplifier 15 is made larger than voltage Vref2, a comparator 27 outputs a signal CE. When a current value from a buffer 11a is made larger than voltage Vref3, a comparator 28 output a signal IE. When the signals FB, FR, CE, IE are input to a CPU 13a or a current value or a voltage value from an A/D converter 18 is made larger than a threshold, an error message is displayed to an output device 20, and the supply of a welding head 7 with currents is stopped.</p> |
