Product Description:

The PSI6300.321-L1 medium-frequency inverter is built by Bosch Rexroth Indramat for the PSI Frequency Inverters series. In an automated cell, it converts the plant’s three-phase supply into a regulated medium-frequency output for induction heating, welding, or brazing processes. The unit is installed inside an electrical enclosure and serves as the power interface between the controller and the work coil or transformer. This role allows the process to apply repeatable thermal energy during each operating cycle.

The inverter accepts a mains supply of 400 – 480 VAC at 50/60 Hz and carries a nominal line current of 110 A, with peak demand rising to 800 A during the energization of inductive loads. Internal control loops run at a 1 kHz clock frequency, and the onboard memory provides 256 parameter registers for ramp and fault-response settings. The control section releases up to 170 W of heat inside the cabinet, and the unit uses air cooling to move heat across the sink surface. Operation is permitted at ambient temperatures up to 55 °C, and the enclosure has an IP20 rating for protection against accidental contact. The housing measures 463 mm in height, 239 mm in width, and 280 mm in depth, which suits standard 600 mm deep panels. Communication is provided through an INTERBUS-S back-plane interface so commands from the master controller can stay synchronized with the power stage.

At full dissipation, the cooling system must remove 360 W from the heat sink. The transformer secondary can deliver up to 36 kA to the workpiece circuit during short pulses. Control electronics use a separate 24 VDC logic supply, which allows supervisory functions and safety relays to remain active when the mains input is isolated. A dedicated INTERBUS timer monitors message intervals to prevent unintended firing sequences. Cooling fan capacity must match the heat-loss values so semiconductor temperatures remain within safe operating limits.