Product Description:

The KDA 3.1-100-3-A00-U1 is a spindle drive produced by Bosch Rexroth Indramat within the KDA Spindle Drives series. It converts regulated DC bus energy from an Indramat supply module into controlled three-phase power for high-speed machine-tool spindles and other rotating loads. By supervising motor current and velocity feedback, the unit holds spindle speed steady during cutting, drilling, or grinding, even when spindle load changes during the machining cycle. In automated lines, it couples the mechanical spindle to the numerical control through an analog reference channel, so the controller can command speed changes without a separate digital interface card.

The drive’s heat sink blower runs from 115 V 50/60 Hz, so the cooling fan can be powered from auxiliary plant mains instead of the DC link. Cooling air is delivered by the mounted heat sink blower, which sweeps heat away from the external fins before it reaches the power section. Internally, logic and IGBT stages draw from a 300 VDC intermediate circuit, which sets the available PWM headroom and resulting motor voltage. Continuous operation at 100 A allows the spindle to accelerate heavy tooling without tripping overcurrent protection. Speed setpoints arrive as an analog speed command, allowing straightforward ±10 V control from common CNC or PLC hardware.

Because it belongs to Series 3, the module includes updated gating logic while omitting legacy interface cards. No additional interface or second encoder socket is provided, which keeps external wiring simpler and leaves the front layout less crowded. The blower operates in forced cooling mode, keeping component temperatures within limits whenever ambient air remains in the 5 to 45 °C range. Full performance is available up to 1000 m installation altitude; above this height, thinner air reduces convective heat transfer and the drive requires derating.