Product Description:

The PSI63C0.776-L2 is a medium-frequency inverter produced by Bosch Rexroth Indramat within the PSI Frequency Inverters series. Intended for automated welding cells, the unit converts high-voltage mains power into precisely timed current for transformer-fed spot-welding guns while coordinating pressure, time, and force with the host controller. By combining control, power, and network interfaces in one enclosure, it supports consistent weld quality and short cycle times in high-volume body-assembly lines.

At the heart of the inverter, a TriCore processor closes the regulation loop in 1 ms and supports a process frequency of 1000 Hz for shaping the secondary current waveform. The controller accepts 26 discrete inputs for gun position, sensor, and safety signals, and it provides 18 discrete outputs for actuator acknowledgment, valve control, and status indication. Programming capacity reaches 256 user programs, each of which can be selected through an Ethernet/IP fieldbus link or the built-in Ethernet timer function. A single switched relay output complements the solid-state channels, and the unit uses forced-air cooling.

Electrical requirements are straightforward. The inverter operates from a three-phase supply of 480–690 VAC and requires a logic supply of 24 VDC. Up to 0.7 A max can be sourced from the dedicated high-current terminal, while auxiliary sensors share a collective 2 A I/O supply budget. The emergency stop circuit is independent and tolerates 24 VDC at 3 A for rapid energy release. Field devices can be wired over distances of up to 100 m without signal regeneration, and the relay contact can be terminated with compression lugs. The control system also provides 10 pressure-profile steps, three weld-time stages, a single-cycle timer, and Ethernet diagnostics for welding sequence monitoring.