| 摘要 |
PURPOSE:To display whether welding current deviates upper and lower limits with a simple circuit by comparing the welding current value fed from an A/D converting circuit and the upper and lower limit current values set by a setting circuit by means of an arithmetic circuit. CONSTITUTION:A current detecting circuit 2 which detects the average analog value of the welding current flowing in base metal to be welded, an A/D converting circuit 3 which converts the analog current value detected by the same to a digital value, a setting circuit 4 which sets the upper and lower limits of the welding current value and a comparator circuit 5 which compares the digital current value converted by the circuit 3 and the upper and lower limit current values set by the circuit 4. The signal indicating the case when the detected welding current exceeds the set upper limit current as a result of comparison in an arithmetic circuit 5 and the case when said values does not attain the lower limit current value is outputted to a display device 6. |
