
The Mitsubishi MDS-B-SP-185 is a high-performance AC spindle drive unit designed for CNC machine tools, providing precise speed and torque control for AC spindle motors. Part of the MDS-B series, this drive unit features advanced IGBT IPM sinusoidal wave PWM inverter circuitry with vector control digital closed-loop technology and pulse generator speed feedback. The unit supports spindle motors with a maximum output capacity of 18.5 kW and delivers 63 A rated output current. Engineered for vibration resistance up to 4.90 m/s² and compatible with Mitsubishi M500 series CNC systems, it operates optimally within a speed range of 35 to 6000 rpm with a maximum speed variation of 0.2 percent. The drive incorporates power regenerative braking, high-speed CPU for precise positioning control, and high-speed serial connection for speed commands, making it ideal for demanding machining applications in milling, turning, and machining centers.
Item Details
- Brand Name: Mitsubishi
- Manufacturer: Mitsubishi Electric
- Item Type Name: Spindle Drive Unit
- Product Family / Series: MDS-B Series
Product Specifications
- max_motor_output_capacity: 18.5 kW
- rated_output_current: 63 A
- input_voltage: 200/220/230 V AC
- speed_range: 35 to 6000 rpm
- max_speed_variation: 0.2 %
- vibration_resistance: 4.90 m/s² (X and Y directions)
- control_technology: Vector control digital closed-loop with pulse generator speed feedback
- inverter_type: IGBT IPM sinusoidal wave PWM
- heat_dissipation_continuous_rated: 190 W
- cnc_compatibility: M500 Series CNC
Additional Details
- Lifecycle Status: Discontinued by manufacturer
- Operating Temperature Range: 0 to +55 °C
- Storage Temperature Range: -15 to +70 °C
- Relative Humidity: Up to 90 % (no dew condensation)
- Max Altitude: 1000 m above sea level
- Special Features: Power regenerative braking, high-speed orientation, zero speed detection output, orientation completion function (ORCF)
All PLC Direct products come with a 1-year warranty. The warranty is issued by PLC Direct. Warranty coverage commences at the date of purchase. The warranty is for mechanical defects or failures not caused by human factors including but not limited to (a) incorrect installation, (b) operating the unit in sub-optimal conditions or in scenarios not recommended by the manufacturer, (c) poor unit maintenance, etc. The warranty does not cover programming or software related issues.
If the product is eligible for PLC Direct’s warranty coverage and the customer encounters an issue with the product, we will request the item is shipped to us for diagnosis and examination. Regardless of the cause of product issues, the customer will bear responsibility for the cost of shipping the unit to PLC Direct for evaluation. Where the unit was damaged by human factors, we will offer a repair or replace quote; in cases where damage was caused by human factors, the customer is responsible for the cost of shipping the repaired/replaced unit from PLC Direct to the customer. Where the unit was not damaged by human factors but is covered by PLC Direct’s warranty, we will repair or replace the unit at our cost (or, in rare cases, refund you your purchase); in such cases, PLC Direct will bear the cost of shipping the repaired or replaced product back to the customer. It is up to PLC Direct’s discretion whether to repair, replace, or refund the customer in such cases. Diagnoses can take time to complete based on technician availability and the complexity of diagnosis.
In no event shall PLC Direct be liable for any damages except actual damages up to, but not exceeding, the amount paid to us for the product, including we shall not be liable for any consequential or indirect damages or lost profits whether or not advised of same.
PLC Direct offers free shipping worldwide. Product ship from a various warehouses worldwide based on the customer's and the product's location. The estimated delivery date on the product page is PLC Direct's best estimated assuming a US-based shipping destination.
Regardless of where the product is shipping from, PLC Direct covers all duties for US-based shipping destinations. For non-US-based shipping destinations, customers are responsible for duties as appropriate.
PLC Direct's focus is on balancing price with lead time. Some but not all products can be expedited. If you have questions about delivery ETAs, please contact our team.

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