Inverter type resistance welding power-supply unit

摘要

PURPOSE:To adjust the exchange time by detecting the charging property of a capacitor charging circuit on the input side of an inverter circuit with an inverter type resistance welding power unit and measuring a time constant. CONSTITUTION:An inverter type resistance welding power unit in which alternating current of commercial frequency is converted into direct current and supplied to a capacitor a capacitor charging voltage is inputted into an inverter circuit is provided with a capacitor charging means through the charging resistance, a charging property detecting means for a time constant including the charging resistance and the capacitor and a capacitor capacity measuring means based on its charging property. In this way, the degradation of the capacitor can be decided and the capacitor can be exchanged.