OKUMA

12” LCD OKUMA Replacement Monitor – TOI12LB1-A248

The TOI12LB1-A248 is a 12-inch industrial LCD monitor (“12” LCD CNC Monitor”) designed as a direct replacement for the CRT monitors fitted to OKUMA operator panels and control systems, as well as other CNC machine tools. The unit accepts multiple analogue video formats (RGB, CGA, EGA, VGA, RGBS) to ensure compatibility with legacy CNC controllers from various generations. The CCFL- or LED-backlit LCD panel delivers a sharper, brighter image than the original cathode-ray tube, with a significantly longer service life and no geometric drift. The main part number is TOI12LB1A248; the commercial alternative code is TOI12LB1-A248.

The monitor is the visual interface through which the operator interacts with the numerical control unit: it displays part programs, machine parameters, diagnostic data, active alarms, and axis status. Replacement becomes critical when the original CRT degrades (blurred image, loss of brightness, distorted geometry, or exhausted tube): without a functioning display the operator cannot verify the part program or acknowledge and reset alarms, rendering the machine completely inoperable.

This is a TOI-series LCD retrofit monitor, specifically configured for plug-and-play replacement of obsolete CRTs on OKUMA controls (and compatible with many other CNC systems). This model is considered legacy / discontinued through standard channels; availability is limited to remaining stock, used units, or reconditioned assemblies.

Main Technical Specifications

AC Spindle Drive – OKUMA VACII D-8A

The VACII D-8A is an AC spindle drive amplifier (“AC Spindle Drive”) manufactured by OKUMA, belonging to the VAC II series of AC spindle drive units. The module is designed to operate within OKUMA CNC systems fitted with the proprietary OSP (OKUMA Servo Pack) controller, typically installed in OKUMA machining centres and CNC lathes produced during the 1980s–1990s. The designation “D-8A” identifies the power/current variant within the VAC II family; it governs AC spindle motor torque and speed, interfacing directly with the OSP controller module.

The spindle drive is the power electronics module that converts three-phase AC mains voltage into variable voltage and frequency for the spindle motor, closing the speed and torque loop based on CNC reference commands. Without it the spindle cannot be speed-controlled or smoothly accelerated and decelerated: any failure causes an immediate machine stop and makes further machining impossible.

OKUMA Corporation is one of Japan’s leading CNC machine tool manufacturers, founded in 1898 and headquartered in Oguchi, Aichi, Japan. It is one of the few manufacturers worldwide to design and integrate the machine, motor, drive and CNC control in-house through the proprietary OSP system. Products in the VAC II series are legacy / discontinued: available exclusively as used spare parts, surplus stock, or through specialist repair services.

Main Technical Specifications

CNC Operator Panel – OKUMA OSP 5000SG-IT

The OSP 5000SG-IT is a CNC operator panel (“CNC Operator Panel”) manufactured by OKUMA Corporation, a component of the OSP 5000SG CNC control unit belonging to the OSP (Open System Platform) series. The panel is the human-machine interface (HMI) of the CNC system: it incorporates the MDI (Manual Data Input) keyboard with an Italian (“IT”) layout, function keys for operating mode selection (AUTO, MDI, HANDLE, JOG), rapid traverse keys, and emergency stop. It connects to the OSP 5000SG main rack via a dedicated cable and serves as the primary interface point for machine programming and control.

The operator panel is the command terminal through which the operator directly interacts with the numeric control: entering and editing part programs, selecting operating modes, performing work origin and tool offset corrections, and monitoring machine status in real time. In the event of failure, the machine is inoperable in any mode — neither manual, MDI, nor automatic — making this component absolutely critical for production continuity.

OKUMA Corporation is a Japanese CNC machine tool manufacturer founded in 1898, the only manufacturer in the world to design machine, motor, and numeric control (OSP series) entirely in-house. The OSP 5000 series, developed in the 1990s, is now legacy / discontinued: official OKUMA support has ended and availability is limited to used components, surplus stock, and specialist repair services.

Main Technical Specifications

CNC Operator Panel – OKUMA OSP 5000 LIT

The OSP 5000 LIT is the operator panel (“Operator Panel”) of the OKUMA OSP5000L CNC control system, manufactured by OKUMA Corporation. It is the main human-machine interface (HMI) of the OSP5000L numerical control, documented on OKUMA CNC machining centres and lathes from the 1990s–2000s era. The panel integrates a display (CRT in early versions, LCD in later revisions), an MDI keyboard for data and programme entry, operating mode selectors, feed rate and spindle speed override potentiometers, manual jog controls and an emergency stop pushbutton. The suffix LIT identifies the Italian-language localised variant. The unit is an integral part of the machine’s electrical cabinet and communicates with the CNC CPU via a dedicated OKUMA panel bus.

The operator panel is the sole access point through which the operator sets up, starts and monitors machining: without it, programmes cannot be entered or edited, tool offsets cannot be corrected, operating modes cannot be selected and alarm messages cannot be read. A panel failure brings the machine to a complete standstill regardless of the condition of the axes, spindle and power electronics, making any production impossible until it is restored.

OKUMA Corporation is a Japanese machine tool builder founded in 1898 in Nagoya, still active and listed on the Tokyo Stock Exchange (TYO: 6103). Unlike most competitors, OKUMA develops both its machine tools and its proprietary OSP (Open System Platform) numerical control in-house, ensuring full hardware/software integration. Products in the OSP5000L series are legacy / discontinued: the platform has been superseded by the OSP-P and OSP-E lines; original panels are available only as used, surplus or through specialist repair.

Main Technical Specifications

Servo Drive Unit – OKUMA MIV22-3-V5

The MIV22-3-V5 is an intelligent vector servo drive (“Motor Intelligent Vector Drive”) manufactured by OKUMA, belonging to the MIV (Motor Intelligent Vector) series. It is designed for use in OKUMA CNC machining centres and lathes equipped with the proprietary OSP (Open System Platform) control system. It handles vector speed and torque regulation of the axis servo motor, receiving digital set-point references from the CNC and driving the power stage accordingly. The designation “MIV22” indicates the rated current class (~22 A); the suffix “3” identifies the variant or number of controlled axes, while “V5” denotes the firmware/hardware revision.

The servo drive is the electronic heart of the axis motion system: it converts the digital references from the OSP control into current supplied to the servo motor, ensuring precise positioning and dimensional repeatability in the machined part. If it fails, the controlled axis loses all ability to move in a controlled manner, rendering the machine unusable and halting production.

OKUMA Corporation, founded in 1898 in Nagoya, Japan, is one of the world’s leading CNC machine tool builders. It is one of the few manufacturers to develop in-house the machine, the numerical control (OSP – Open System Platform), and the motors and drives, ensuring full system integration. Components of the MIV series in older versions are legacy / discontinued and primarily available as refurbished used parts or through specialist repair services.

Main Technical Specifications

Axis CNC Servo Drive – OKUMA MIV45-3-V5

The MIV45-3-V5 is a digital CNC axis servo drive (“Axis Servo Drive”) manufactured by OKUMA Corporation, a component of the axis control architecture in OKUMA CNC machining centres and lathes equipped with the proprietary OSP (Open System Platform) numerical control. The unit receives position and speed references from the NC board via OKUMA’s proprietary serial bus and digitally manages the current, speed, and torque loops of the AC servo motors driving the machine axes. The suffix V5 identifies the hardware/firmware revision within the MIV45 series; the number 3 denotes the axis configuration variant of the unit.

The servo drive is the component that converts digital commands from the CNC into phase currents for the machine axis AC motors, closing the position, speed, and torque control loops in real time. A failure immediately triggers an axis alarm and halts machining; an uncontained following error can cause collisions or dimensional rejects, making this drive critical for both process safety and part quality.

OKUMA Corporation is one of the world’s leading CNC machine tool manufacturers, founded in 1898 in Oguchi, Aichi, Japan. It is the only builder that designs and manufactures machines, motors, drives, and the numerical control system (OSP) entirely in-house, ensuring full vertical integration. Components in the MIV series belong to OSP control generations that are now in an advanced stage of their life cycle: availability as new spare parts is very limited, and specialist repair or authorised OKUMA distributors are strongly recommended.

Main Technical Specifications

CNC Power Supply – OKUMA MPS 20

The MPS 20 is a panel-mount CNC control power supply (“Main Power Supply”) manufactured by OKUMA, used as the power supply unit in OSP (Open System Platform) numerical control systems fitted to OKUMA machine tools. The module converts mains voltage into regulated DC voltages (+5 V, ±15 V, +24 V DC typical) required by the CPU boards, I/O modules and drive electronics of the control. Documented on machining centres and CNC lathes of the LB, LR, MA, MB series and OSP3000 / OSP5000 control systems.

The MPS 20 power supply is the backbone of the CNC control system’s energy supply: without stable, filtered voltages all logic boards, servo modules and the operator panel cease to function immediately. A power supply failure results in complete machine downtime and, in the most serious cases, loss of position data with the risk of mechanical interference on restart.

OKUMA is a Japanese manufacturer founded in 1898 and one of the world’s leading producers of CNC machine tools and proprietary OSP control systems. The exclusive integration between machine and control ensures optimal performance but makes spare parts dependent on the OKUMA supply channel. Components in the MPS series for first- and second-generation OSP systems are legacy / discontinued: available only as used, surplus or through specialist repair.

Main Technical Specifications

CNC Power Supply – OKUMA MPR5

The MPR5 is a switching power supply unit for CNC control systems (“CNC Power Supply Unit”) manufactured by OKUMA, designed to power the electronic circuits of CNC control systems in the OSP (Open System Platform) series. The module delivers multiple regulated voltages required by control boards, I/O interfaces and logic circuits of the CNC unit. The commercial reference is MPR5; in some systems the module is integrated into the control rack or mounted on a dedicated panel. Compatible with OKUMA lathes, machining centres and grinding machines from the 1980s–2000s.

The power supply is the critical component that converts and distributes electrical energy to all circuits of the CNC control: an unstable voltage or an out-of-specification output causes malfunctions, safety shutdowns or irreversible damage to logic boards. Its failure renders the machine completely inoperable, halting production until the module is replaced or repaired.

OKUMA Corporation, founded in 1898 in Oguchi (Aichi, Japan), is one of the world’s leading CNC machine tool manufacturers. Unlike many competitors, OKUMA develops its entire control chain in-house — CNC controls, motors, drives and power supplies — ensuring optimal integration and advanced diagnostics. Components in the MPR series belong to an earlier generation of CNC systems: these are legacy / discontinued products, available exclusively as used, surplus or through specialist repair services.

Main Technical Specifications

Servo Axis Drive Module – OKUMA MIV30-3-V5

The MIV30-3-V5 (catalogue code MIV303V5) is a servo axis drive module (“Servo Axis Drive Module”) manufactured by OKUMA, designed for OKUMA CNC machining centres and lathes equipped with the OSP control system (Open System Platform). The module closes the speed and current regulation loops for the axis servo motors, receiving references from the CNC control unit via the proprietary internal communication bus and generating the three-phase PWM-modulated output to the servo motor. The MIV designation identifies servo drive modules within the OKUMA drive family; the “30” suffix typically indicates the peak current rating (approximately 30 A), while “V5” identifies the hardware and firmware variant/revision.

The servo axis drive module is the power electronics component that converts digital commands from the CNC into precisely modulated electrical power to drive the axis servo motor. It ensures accurate position, speed and torque control on each controlled axis. In the event of failure, the axis can no longer be controlled: the machine triggers an immediate alarm with motion lockout and no machining operation is possible until the module is replaced or repaired.

OKUMA is one of Japan’s leading CNC machine tool manufacturers, founded in 1898 in Nagoya, Japan. Unlike most competitors, OKUMA designs and manufactures both the machine tools and the CNC control systems (OSP series) in-house, ensuring full integration between mechanics and electronics. MIV-series modules intended for earlier-generation OSP controls are legacy / discontinued: availability is limited to used parts, NOS/surplus stock, or specialist repair services.

Main Technical Specifications

Servo Drive Module – OKUMA MIV08-1-B5

The MIV08-1-B5 is a servo drive module (“Servo Drive Module”) manufactured by OKUMA Corporation, a component of the axis control system for OKUMA CNC machine tools equipped with the proprietary OSP (Open System Platform) numerical control. The module manages speed, torque, and position regulation for a servo axis, interfacing with the CNC via the OKUMA proprietary serial bus. The alternate part number MIV081B5 identifies the same component in the OKUMA spare parts catalogue. The component may exist in multiple hardware revisions.

The servo drive module is the core of the axis control loop for the machine’s linear or rotary axes: it converts digital commands from the CNC into motor supply current, closing the position, speed, and torque loops in real time. A failure of this module causes immediate locking of the affected axis and halts the machining cycle, rendering the machine inoperable until the component is replaced or repaired, with consequent production downtime.

OKUMA Corporation is one of Japan’s leading CNC machine tool builders, founded in 1898 in Nagoya. It is distinguished by its vertically integrated design of machines, CNC controls (OSP series), and drives — all developed and manufactured in-house. Components in the MIV series are legacy / discontinued: available only as used/surplus or through specialist repair services.

Main Technical Specifications

Servo Drive Module – OKUMA MIV0101-1-B1

The MIV0101-1-B1 is a servo drive module (“Servo Drive Unit”) manufactured by OKUMA, a component of the axis control system for OKUMA CNC machine tools equipped with the OSP (Open System Platform) controller. The module manages speed, torque, and position regulation of a brushless servo motor, receiving commands from the CNC via a proprietary bus and returning position/speed feedback via a dedicated encoder. The part number MIV0101-1-B1 identifies hardware revision B1 of the MIV0101 family; other hardware revision variants may exist.

The servo drive module is the power and control element that converts CNC digital references into phase currents for the axis motor: it closes the position, speed, and current loops, ensuring the positioning accuracy typical of OKUMA machine tools. A module failure triggers the corresponding axis alarm, disables axis movement, and immediately stops the machine, preventing production from resuming until the unit is replaced or repaired.

OKUMA Corporation is a Japanese manufacturer founded in 1898 in Nagoya, specialising in CNC machine tools (lathes, machining centres, grinding machines) and the in-house OSP (Open System Platform) control systems developed entirely internally. It is one of the few manufacturers in the world that designs the machine tool, the CNC controller, and the drives entirely in-house. Products of the MIV series are legacy / discontinued: available exclusively as used, surplus, or through specialist repair services.

Main Technical Specifications

AC Servo Drive – OKUMA MIV08A-1-B5

The MIV08A-1-B5 is a digital AC servo amplifier (“AC Servo Drive”) manufactured by OKUMA, belonging to the MIV series of axis servo amplifiers. The unit is designed to operate within OKUMA CNC systems equipped with OSP (Open System Platform) controllers, covering the OSP5000, OSP7000, and OSP-U generations. It is documented on OKUMA machining centres and CNC lathes of the LB, MB, and MC series. The designation “08A” indicates a nominal output current of approximately 8 A; the suffix “B5” identifies the hardware variant and revision of the module.

The servo drive closes the position, speed, and torque control loops of a linear or rotary machine axis: it receives digital commands from the OKUMA CNC via the proprietary serial bus and generates the three-phase current required to power the servo motor, ensuring fast and repeatable positioning. A drive failure immediately stops the affected axis with a CNC alarm, rendering the machine inoperable; in severe cases it may result in position loss or an axis crash.

OKUMA Corporation, founded in 1898 in Oguchi, Japan, is one of the world’s leading manufacturers of CNC machine tools and control systems. OKUMA develops its machine tools, OSP controllers, and servo components entirely in-house, ensuring full hardware and software integration. Products in the MIV series are legacy components of the OSP system and are legacy / discontinued: available only as used stock, surplus, or through specialist repair services.

Main Technical Specifications

Drive Inverter Module – OKUMA MIV08-3-V1

The MIV08-3-V1 is an electronic drive inverter module (“Drive Inverter Module”) manufactured by OKUMA, documented as a component of the servo and spindle drive systems for OKUMA CNC machine tools equipped with OSP (Open System Platform) controllers. The module performs DC-to-AC power conversion and current/speed regulation for servo axes or spindle motors, operating within OKUMA’s integrated proprietary drive architecture. The MIV designation identifies inverter modules within the OKUMA drive family; the suffix 08 denotes the current/power size variant, 3 the sub-variant, and V1 the hardware revision.

The MIV08-3-V1 inverter module is the core power electronics component that converts DC bus voltage into variable-frequency, variable-voltage AC power for the connected servo or spindle motor, closing the current and speed loops under command from the OSP controller. In the event of failure, the axis or spindle managed by this module becomes completely inoperative and the machine cannot carry out any machining operations; the proprietary and integrated nature of the OKUMA system makes this component critical and non-interchangeable with generic equivalents.

OKUMA Corporation, founded in Nagoya (Japan) in 1898, is one of the world’s leading manufacturers of CNC machine tools and integrated control systems. The company develops its own controllers (OSP), drives, and motors as a closed proprietary system, making spare parts in this series exclusive and non-interchangeable with other brands. Modules in the earlier-generation MIV family are legacy / discontinued: available only as used, surplus, or through specialist repair services.

Main Technical Specifications

AC Servo Drive – OKUMA MIV0404A-1-B5

The MIV0404A-1-B5 is an AC vector servo drive (“AC Servo Drive”) manufactured by OKUMA Corporation, belonging to the MIV series (Motor Interface Vector) used in OKUMA CNC systems with the proprietary OSP control (Open System Platform). The unit converts digital CNC commands into current and voltage signals for the AC brushless motor of the controlled axis, managing the current and speed loops in vector mode. The part number MIV0404A-1-B5 identifies the MIV series, current class 04 A, hardware revision A-1 and mechanical/firmware variant B5.

The servo drive is the power and regulation module that translates position and speed references generated by the OSP control into variable current for the axis motor: it closes the current and speed loops ensuring precise and repeatable motion during machining. A drive failure renders the controlled axis completely inoperative, immediately stopping the machine; as a proprietary OKUMA electronic component, availability as new is nil and sourcing relies exclusively on the surplus market and specialist repair.

OKUMA Corporation is a Japanese machine tool builder founded in 1898 in Nagoya, a pioneer of vertical integration in the CNC sector through the in-house production of machines, controls and drives. The proprietary OSP control and the associated MIV-series drives are legacy / discontinued: no longer available as new through official OKUMA channels, sourced exclusively as used surplus stock or through specialist repair providers.

Main Technical Specifications

CNC Axis Servo Drive Unit – OKUMA MIV0404-1-B5

The MIV0404-1-B5 is a CNC axis servo drive unit (“Axis Servo Drive / Motor Inverter”) manufactured by OKUMA Corporation, a core motion control component in OKUMA CNC machine tools equipped with the proprietary OSP (Open System Platform) control system. The unit digitally regulates position, speed and torque of the axis servo motor, interfacing directly with the CNC unit via the OKUMA proprietary serial bus. The MIV designation identifies the “Motor Inverter” family within the OKUMA servo architecture; the B5 suffix denotes the hardware revision of the module. The alternative commercial part number is MIV04041B5.

The servo drive is the power and control module that receives position and speed references from the CNC and supplies the axis motor with the current required to follow the programmed path with maximum precision. In the event of failure, the affected axis is completely blocked or uncontrollable: the machine cannot perform any machining operations and is taken out of service until the drive is replaced or repaired, with extended production downtime due to the proprietary nature of the component.

OKUMA Corporation, founded in 1898 in Nagoya, Japan, is one of the world’s leading manufacturers of CNC machine tools (machining centres, lathes, grinders) and proprietary OSP control systems. Unlike many competitors, OKUMA designs and builds both its machine tools and CNC controls entirely in-house, ensuring full integration while binding maintenance to original spare parts. Components in the MIV series belong to superseded OSP generations and are considered legacy / discontinued: available only as used stock, surplus or through specialist repair.

Main Technical Specifications

Servo Drive Module – OKUMA MIV02-1-B1

The MIV02-1-B1 is a servo drive module (“Servo Drive Module”) manufactured by OKUMA, belonging to the MIV series (Motor Inverter Vector) of the integrated drive system for OKUMA machining centres and CNC lathes equipped with the OSP (Open System Platform) control. The module manages the current and speed regulation loops for linear or rotary axis drives, interfacing with the axis control board and the drive power stage on a proprietary rack. The designation MIV02-1-B1 identifies size class 02 (small to medium power rating), hardware revision B, issue 1.

The servo drive module is the core of the machine’s axis motion control: it receives position and speed references from the CNC and closes the regulation loops on the motor, ensuring geometric accuracy on each axis during machining. A failure of this module causes the immediate stop of the corresponding axis and makes it impossible to execute any machining cycle; in severe cases it may result in uncontrolled axis movement with risk of mechanical collision.

OKUMA is one of the world’s leading CNC machine tool builders, founded in Japan in 1898. The company is notable for its complete vertical integration: it designs and manufactures its CNC control (OSP – Open System Platform), drives and motors entirely in-house, ensuring long-term compatibility and support. Components in the MIV series belong to an older control generation and are legacy / discontinued: sourcing is possible only as used, surplus, or through specialist repair.

Main Technical Specifications

Servo Axis Drive Module – OKUMA MIV0204A-1-B5

The MIV0204A-1-B5 is a servo axis amplifier module (“Servo Amplifier Module”) manufactured by OKUMA Corporation, forming part of the axis control chain in OKUMA machining centres and lathes equipped with the OSP (Open System Platform) CNC control. The module handles speed and torque regulation of the servo axis motor, interfacing with the CNC unit via the proprietary OKUMA serial bus and with the drive power stage. The MIV designation identifies the OKUMA servo amplifier family; the suffix A-1-B5 specifies the power and hardware configuration variant. This is not a CPU module or spindle drive, but a dedicated amplifier for a single machine axis.

The servo axis drive is the electronic module that converts position and speed commands from the CNC into drive current for the axis motor: it closes the speed and torque loop, ensuring positioning accuracy and dynamic stiffness during machining. In the event of failure the module triggers an alarm that immediately stops the controlled axis — and often the entire machine — making any cutting operation impossible until the drive is replaced or repaired.

OKUMA Corporation is a Japanese machine tool manufacturer founded in 1898, headquartered in Oguchi, Aichi, Japan. It is one of the few manufacturers worldwide to integrate machine tool, CNC control (OSP series) and servo drives entirely in-house, guaranteeing full system compatibility. Products in the MIV family are legacy / discontinued: no longer available new through the official OKUMA network and sourced exclusively as used, surplus or via specialist repair.

Main Technical Specifications

Servo Drive Module – OKUMA MIV0203-1-B1

The MIV0203-1-B1 is an electronic servo drive module (“Servo Drive Module”) manufactured by OKUMA Corporation, a component of the OSP (Open System Platform) CNC control architecture installed on OKUMA machine tools. The module handles speed and current regulation for a servo axis, receiving references from the OSP internal bus and driving the axis brushless motor. It is also identified by the compact part number MIV02031B1; the “B1” suffix denotes the specific hardware revision.

The servo drive module is the axis controller that converts position and speed commands from the CNC into controlled motor current, closing the feedback loops in real time. Without this module the controlled axis does not respond to commands: the machine generates an axis alarm and cannot perform any machining operation. A fault typically manifests as axis positioning loss, axis drift, abnormal vibration, or immediate production cycle shutdown.

OKUMA Corporation, founded in 1898 in Nagoya, Japan, is one of the world’s leading CNC machine tool builders and the only major manufacturer to develop both the machine and its integrated CNC control system (the OSP – Open System Platform). Modules in the MIV series belong to the OSP-P200 / OSP-P300 control generations and are legacy / discontinued: available exclusively as used, NOS surplus, or through specialist repair services.

Main Technical Specifications

Servo Axis Drive – OKUMA MIV01-1-B5

The MIV01-1-B5 is a single-axis CNC servo drive amplifier (“Single-Axis Servo Drive Amplifier”) manufactured by OKUMA, belonging to the MIV series of servo amplifiers for linear axis control. Designed for integration with the OSP (Open System Platform) CNC control, it manages current and velocity regulation of the axis servo motor, receiving position and velocity references from the control and closing the servo loop on the machine axis. The suffix B5 identifies a specific variant of the unit.

The axis servo drive is the component that converts CNC motion commands into servo motor drive current: it regulates motor torque and velocity in real time, ensuring interpolation and positioning accuracy on the axis. If it fails, the control raises a servo alarm and the affected axis loses all control: the machine stops and machining cannot resume until the drive is replaced or repaired.

OKUMA is one of Japan’s largest CNC machine tool manufacturers, founded in 1898 and headquartered in Oguchi, Aichi Prefecture; it produces lathes, vertical and horizontal machining centres, and OSP control systems with full vertical integration between machine and control. Products in the MIV series are legacy / discontinued: available exclusively as used, surplus, or through specialist repair services.

Main Technical Specifications

Axis Servo Drive Module – OKUMA MIV0103-1-B1

The MIV0103-1-B1 is a digital axis servo drive module (“Axis Servo Drive Module”) manufactured by OKUMA, belonging to the MIV (Motor Inverter) drive family used in OKUMA CNC machining centres and lathes equipped with the OSP (Open System Platform) control. The main catalogue part number is MIV01031B1. The module converts the DC bus voltage from the main power supply unit into three-phase current for the axis brushless servo motor, receiving position and speed references from the CNC via the OKUMA proprietary bus. The module may be available in revision variants indicated by the alphanumeric suffix (e.g. B1).

The axis servo drive is the component that translates the CNC’s digital commands into motor drive current, closing the position, speed and current control loops in real time. A failure renders the corresponding axis uncontrollable: the machine triggers an alarm and machining stops immediately. The dynamic response of the drive is critical for positioning accuracy, surface finish quality, and cycle repeatability.

OKUMA Corporation is a Japanese CNC machine tool manufacturer founded in 1898, headquartered in Oguchi, Aichi, Japan. It is one of the few manufacturers in the world to develop both machine tools and its own proprietary CNC system (OSP — Open System Platform) in-house, ensuring full vertical integration between mechanics, drives and control electronics. Components of the MIV series are legacy / discontinued: available exclusively as used, surplus, or through specialist repair services.

Main Technical Specifications

BDU Servo Drive Board (Base Drive Unit) – OKUMA E4809-032-498-B

The E4809-032-498-B is a BDU servo drive board (“Base Drive Unit”) manufactured by OKUMA, a key component of the integrated servo drive system fitted to OKUMA OSP (Open System Platform) CNC machining centres and lathes. The board manages the base drive stage of the servo amplifier: it generates PWM signals for the power stage (IGBTs) and closes the current regulation loop on the motor. It is documented on machines in the OKUMA MA, MB, MH (machining centre) and LB, LU (lathe) series equipped with OSP-5020L / OSP-7000L controls. The part number belongs to the standard OKUMA nomenclature for the E4809 family, reserved for electronic boards within servo and spindle drive assemblies.

The BDU board is the electronic module that converts the torque and current commands from the CNC controller into gate-drive signals for the servo power stage IGBTs. Without it the controlled axis or spindle loses its drive entirely: the machine triggers an immediate alarm and no controlled movement is possible. A BDU failure typically presents as overcurrent alarms, loss of feedback, or failure to enable the axis.

OKUMA Corporation is a Japanese CNC machine tool builder founded in 1898, specialising in lathes, machining centres, and grinding machines together with its own OSP (Open System Platform) CNC control system. OKUMA is one of the very few manufacturers worldwide that vertically integrates the design and production of the machine, the CNC, and the drives in-house. Products in the E4809 series belong to earlier OSP generations and are legacy / discontinued: available only as used, NOS, or through specialist repair services.

Main Technical Specifications

AC Servo Drive Unit BL-II Series – OKUMA BLII-D50/50A

The BLII-D50/50A is an AC brushless servo drive module (“AC Servo Drive Unit”) belonging to OKUMA’s BL-II (Brushless II) series, designed for closed-loop axis control on the Japanese manufacturer’s CNC machine tools. The designation identifies a 50 A rated unit from the second generation of OKUMA brushless drives, typically installed in vertical and horizontal machining centres and CNC lathes equipped with OSP controllers (OSP5000, OSP5020, OSP700 and related variants), produced from the late 1980s through the early 1990s. The unit manages current and speed regulation of the axis motor, interfacing with the CNC controller via a proprietary OKUMA bus and with the motor via incremental encoder or resolver. Available in multiple size variants; compatibility with the specific machine model and hardware revision must always be verified before replacement.

The servo drive is the power electronics unit that converts position and velocity commands from the CNC into phase current for the brushless axis motor: it closes the current loop in real time and ensures each axis follows the programmed trajectory with precision. In the event of a fault the affected axis becomes uncontrollable and the machine stops immediately with an alarm — production cannot resume until the module has been replaced or repaired, making this component critical for plant operational continuity.

OKUMA Corporation is a Japanese manufacturer of CNC machine tools founded in 1898 in Nagoya; it is one of the few manufacturers in the world to design and produce both machine tools and CNC controllers (OSP – Open System Platform), motors, and servo drives entirely in-house, ensuring full vertical integration that delivers high performance but results in strictly proprietary components. Products in the BL-II series are legacy / discontinued: procurement is possible only through used, surplus, or specialist repair channels.

Main Technical Specifications

BL-II Brushless Servo Drive – OKUMA BLII-D50/30A

The BLII-D50/30A is a brushless servo drive (“BL-II Brushless Servo Drive”) manufactured by OKUMA, belonging to the BL-II (Brushless II) family of the OSP (Open System Platform) axis control system. The unit is rated for a nominal output current of 30 A within the D50 series, designed to control brushless servo motors on the linear and rotary axes of OKUMA CNC machining centres and turning centres. It interfaces with the CNC unit via the OKUMA proprietary bus and receives feedback from the resolver or encoder mounted on the servo motor.

The servo drive closes the current and speed loops on the motor of the controlled axis: it converts the torque and speed reference from the CNC into precise phase current to the brushless motor, ensuring accurate positioning and high dynamic response during machining. If the drive fails, the corresponding axis becomes inoperative and the machine trips into alarm; production cannot resume without replacement or repair of the unit.

OKUMA Corporation is a Japanese machine tool builder founded in 1898 in Nagoya, a world leader in CNC machine tools with the proprietary OSP control system. The BL-II series represents a drive generation developed during the 1990s and 2000s, now legacy / discontinued, superseded by the OSP-P platforms and their next-generation drives.

Main Technical Specifications

Brushless Axis Servo Drive – OKUMA BL-D30A

The BL-D30A is a brushless servo drive (“Brushless Servo Drive”) manufactured by OKUMA, designed as an axis drive component for OKUMA CNC machine tools equipped with the proprietary OSP control (Open System Platform – e.g. OSP5000, OSP7000). The module integrates the current and velocity control loops for OKUMA BL-series brushless servo motors, interfacing with the OSP controller via a dedicated internal bus. The part designation identifies the BL Drive family in the configuration with a typical nominal output current of 30 A. The unit may exist in multiple hardware revisions; compatibility with the target machine’s control system and serial number must be verified before installation.

The brushless servo drive is the heart of every controlled-axis drive system in the machine: it receives position and velocity commands from the CNC, closes the feedback loops on encoder and motor current, and generates the three-phase current required to move the servo motor with the required precision. A failure of the BL-D30A completely disables the corresponding axis, rendering the machine inoperable; latent faults in the drive can cause loss of position reference, uncontrolled movements, or damage to the workpiece in progress.

OKUMA Corporation is one of the world’s leading CNC machine tool manufacturers, founded in Japan in 1898. It is renowned for full vertical integration: it designs and manufactures CNC controls (the OSP system), brushless motors, and drives entirely in-house, ensuring optimised compatibility and performance across all components. OKUMA electronic spare parts are highly proprietary and not interchangeable with other brands; for legacy models such as the BL-D30A, availability is limited to the used/surplus market and specialist repair services.

Main Technical Specifications