Product Description:

The KDA 3.1-050-3-D00-W1 belongs to the KDA Spindle Drives series from Bosch Rexroth Indramat. This unit is a dedicated spindle drive that receives digital reference data from a CNC controller and modulates armature current to run high-speed machining spindles with closed-loop accuracy. By converting the fixed DC link voltage into three-phase output for the motor, it supports precise acceleration, deceleration, and steady-state operation in production milling, turning, and grinding centers. This allows the drive to keep spindle speed stable during cutting loads and rapid speed changes commanded by the machine program.

The drive supplies up to 50 A of continuous output current. This is the maximum motor load it can sustain without overheating. Its power section is fed from a regulated bus of 300 VDC; this fixed DC level is produced by an external supply module and sets the peak voltage available at the motor terminals. Safe operation is allowed in ambient temperatures from 5 to 45 °C, so cabinet cooling must keep internal air within that range. Installation is limited to altitudes no higher than 1000 m above sea level, because thinner air reduces convection above that point. Thermal management relies on forced cooling, and the blower is powered by an auxiliary line of 220 V/50–60 Hz so airflow is maintained independently of the DC bus. This arrangement separates cooling power from the converter output stage during standby or fault conditions.

The cooling hardware is integrated as a mounted heat sink blower, eliminating the need for external ducting and simplifying cabinet layout. Speed reference data enter as a digital 16-bit parallel word, giving fine resolution for velocity commands and allowing the drive to follow rapid setpoint changes issued by the CNC. Expansion is limited because there is no additional interface option, and the design also omits a second encoder input, so feedback must come solely from the primary spindle transducer.