| 摘要 |
PROBLEM TO BE SOLVED: To provide a power source device for welding, which can stabilize power generation by maximally continuing switching operation of a switching element, while protecting the switching element from overheating.SOLUTION: A second temperature threshold is newly set at a temperature lower than a first temperature threshold employed for determining operation halt of an inverter circuit 14, and when a detected temperature of a switching element 14a goes over the second temperature threshold, a control circuit 20 switches the inverter circuit 14 from a normal-frequency drive to a low-frequency drive. |
