Product Description:

The VACII D22 spindle drive belongs to the VAC Spindle Drives series manufactured by Okuma. Designed for CNC machine tools, the unit converts commanded speed signals into precise spindle rotation while exchanging operating data with the numerical control. It serves as the power interface between the machine’s main spindle motor and the control cabinet, regulating acceleration, braking, and standstill torque in automated machining centers.

Front-panel feedback is provided by a seven-segment LED status indicator and two discrete lamps. When the charge circuit is energized, the lamp glows orange, confirming that the DC link remains at a hazardous voltage level. Normal operating readiness is indicated by a green status light. Alarm messages begin with the AL prefix, followed by a numeric code that corresponds to a detailed fault description in the control software. Two independent display modes are available; selecting mode code 2 shows the drive temperature and bus voltage in real time, while the alternate mode displays spindle speed data. During machine idle, the control issues standstill command 02, instructing the inverter to hold the spindle magnetically without applying a mechanical brake.

Motion commands are encoded as hexadecimal values that the drive decodes through the XB-EX(CN1) I/O connector. A clockwise spindle request is transmitted as code 03; the inverter then accelerates the motor in the positive direction until it reaches the commanded speed. Counterclockwise rotation uses code 04, reversing the power sequence applied to the stator. For contouring tasks that require the spindle to operate as an additional axis, the control sends C-axis code 06, enabling position-synchronized stopping. Winding selection is also controlled through software. Selecting the H setting engages the high-winding coil set for maximum torque, while the low-winding option, identified by code L, reduces current demand during light cuts.