Product Description:

The DMA 085B 6311-D is a drive module manufactured by Bosch Rexroth Indramat within the DMA Servo Drive Modules series. As a three-phase module for synchronous and asynchronous motors, it converts the rectified DC link into controlled three-phase output that regulates motor torque and speed in automated machinery and material-handling cells. It is intended for servo systems that require stable power conversion and precise motor control from a shared DC bus.

The nonregulated DC link reaches 715 VDC, while the regulated stage is limited to 670 VDC so the control electronics see a stable bus voltage. At a 4 kHz PWM carrier, the module can deliver a continuous current of 47 Arms. When the switching frequency rises to 8 kHz, the continuous rating drops to 31 Arms because switching losses increase. The derating factor is 0.95 A/K, meaning the usable current decreases by 0.95 amperes for each degree that the ambient temperature rises above the reference point. Air cooling through the backplane removes this heat, and an IP20 housing allows installation inside ventilated cabinets without direct exposure to dust or liquid contaminants.

For accelerations or shock loads, the module supplies a peak of 86 Arms at 4 kHz, or 63 Arms when operated at the factory-set 8 kHz switching frequency. Cabinet planners must reserve up to 380 W for internal power loss, and the unit uses a 24 V control supply that draws 1.35 A during normal operation. The 100 mm width supports dense rack layouts, while the 11.5 kg mass helps provide stable cabinet mounting. Encoder interfaces accept sine feedback up to 50 kHz or combined sine/cosine feedback up to 800 kHz, allowing the module to work with high-resolution position sensors. Operation is permitted at ambient temperatures up to 45 °C, and the standard version does not include special sealing or conformal coating.