Product Description:

The PSI63C0.620L1 medium-frequency inverter is produced by Bosch Rexroth Indramat as part of the PSI Frequency Inverters series. Designed for resistance welding lines and induction heating stations, the unit converts three-phase mains power into a regulated medium-frequency output that lets transformers deliver tightly controlled current to the workpiece. Mounted inside a control cabinet, it integrates power conversion and supervisory electronics so that production cells can adjust energy delivery, monitor temperatures, and execute rapid stop sequences through standard 24 VDC logic.

At idle, the cabinet dissipates 69 W of heat, a figure that rises to 170 W when the inverter runs at full load. Because the assembly is air-cooled, inlet air must remain below 45 °C to protect the power semiconductors. The housing carries a protection rating of IP20, which means live conductors are finger-safe while the enclosure remains open to dust and water. A three-phase supply can deliver up to 110 A of nominal current, and the switching devices account for as much as 360 W of cooling loss. Incoming cables require a minimum 35 mm² cross-section, while the output terminals accept conductors up to 50 mm². The discrete I/O rail operates at 24 VDC, and the stop circuit can absorb 3 A without external relays.

During welding impulses, the inverter can source a peak primary current of 800 A, while the secondary side of the welding transformer may reach up to 36 kA. Energy is modulated at a sequence standard of 1000 Hz, allowing small transformer cores and precise thermal management. Stable operation is maintained in ambient temperatures up to 55 °C when ventilation follows the stated airflow figures. Timer functions are handled through the DeviceNet interface, letting the controller apply squeeze, weld, and hold intervals without external timing hardware.