Product Description:

The RD52.1-7N-055-L-V1-FW is a drive controller produced by Bosch Rexroth Indramat for the RD 500 Drive Controllers series. It interfaces between the plant DC bus and induction or synchronous motor groups to regulate torque and speed in automated material-handling lines, packaging equipment, and process machines. By monitoring bus voltage, motor feedback, and external commands, the unit converts incoming DC energy into a three-phase output waveform that matches the commanded operating point. This arrangement allows the connected motor group to accelerate, hold speed, and respond to changing process loads without direct line-frequency operation.

This controller delivers a continuous mechanical output of 55 kW, allowing it to support medium-sized pumps or extruders in continuous-duty applications without derating. The DC input window of 530 to 670 V gives flexibility when several inverters share a common rectifier on the same bus. Motor regulation is executed with field-oriented vector control, so current is separated into flux-producing and torque-producing components for precise dynamic response. Internal heat is removed by forced air cooling, which pushes air through dedicated channels to keep the power semiconductors within their thermal limits during sustained operation. For braking events, energy must be diverted to an external resistor because the unit is supplied without a built-in brake chopper.

An auxiliary circuit provides 24 V standby power, letting the control electronics remain active while the power stage is de-energized during safety stops or service work. The DC link is fed from an inverter DC source, enabling modular layouts in which several drives tap the same bus and share centralized upstream conversion hardware. The hardware is design generation 1, matching the earliest RD 500 mechanical footprint and option-card arrangement. Application software is not included, and firmware must be ordered separately.