The CACR-SR01AB2ER is a discontinued full-digital AC SERVOPACK from Yaskawa VS-800 CACR-SR CNC servo series, developed to pair with 0.1kW ultra-low inertia miniature USAREM servo motors for early Yasnac analog CNC control systems. It adopts three-loop full digital closed-loop control architecture optimized for analog speed command signals, featuring compact rack plug-in structure and built-in power braking circuit. Equipped with multi-stage analog noise suppression filters to counteract electromagnetic interference in metal machining workshops, this unit delivers stable ultra-low speed torque output for micro feed axes. It has standardized CNC-oriented I/O layout without customized OEM suffix, mainly used for spare part replacement of aging miniature CNC auxiliary axes, analog speed and torque control as core operation modes with limited auxiliary pulse positioning function, and complete hardware interlock protection to guarantee precise micro motion control.

CACR: General series identifier of Yaskawa AC servo SERVOPACKSR: CNC-dedicated sub-series optimized for analog speed control signals01: Rated matching motor power, 0.1 kilowattsAB: Special hardware specification code; rack plug-in mounting structure, dedicated analog signal processing circuit, enhanced common-mode filter circuits, integrated braking power transistor module, terminal layout different from wall-mounted BA/BB general servo models2: Second-generation hardware revision of the main control boardER: Encoder matching specification, compatible with 15-bit composite incremental-absolute encoders, equipped with dedicated shielded multi-core encoder wiring terminals

Power input only supports three-phase 200–230V AC with ±10% allowable voltage fluctuation; single-phase power supply is not compatible with this AB rack variant. Rated continuous output current is 2.1A, peak instantaneous output current reaches 6.3A to provide triple short-time overload torque for quick startup of micro light-load axes. Maximum control loop bandwidth reaches 340Hz, cooperating with 15-bit absolute encoder feedback to achieve ultra-high repeated positioning accuracy for miniature motion axes. Continuous operating ambient temperature ranges from 0°C to 40°C; storage temperature spans -20°C to 70°C, relative humidity limited between 5% and 80% with no condensation allowed. Unit protection grade is IP20 for cabinet rack installation, vibration resistance complies with standard machine tool industrial criteria covering 10–1500Hz. Multi-layer built-in safety protection covers overvoltage, undervoltage, overcurrent, overload, overheat, encoder disconnection, motor phase loss, emergency stop hardware interlock and braking circuit abnormality detection. Standard heat dissipation adopts forced air cooling with built-in tiny cooling fan, total unit weight is approximately 1.2 kilograms.

The primary command input channel is 0 to ±10V analog voltage interface preset for speed control mode, switchable to torque command mode via internal parameter configuration; a reserved differential pulse input channel only supports simple auxiliary positioning with limited adjustable parameters. Isolated digital input terminals receive servo enable, alarm reset, positive/negative travel limit, proximity homing switch and CNC safety interlock signals. Digital output terminals use relay isolation to feed back servo ready, speed arrival, positioning completion and drive fault alarm signals to Yasnac host controllers. Dedicated encoder terminal block processes A/B/Z phase differential signals and absolute encoder backup battery wiring, with independent shielding grounding terminals to suppress long-distance wiring signal attenuation and interference. Built-in RS422 serial communication port exclusively matches Yaskawa handheld operator panel for parameter modification, real-time operating data reading and fault history record inquiry; no native industrial fieldbus interfaces are factory pre-installed. Power terminal blocks include three-phase main power R/S/T input, U/V/W motor power output, external braking resistor expansion port and safety grounding terminal, all fitted with lockable wiring structures to prevent terminal loosening under long-term machine vibration. All analog signal circuits integrate independent multi-stage common-mode filter circuits to adapt complex electromagnetic environments of machining workshops.

Full digital independent adjustable gain parameters for current, speed and position closed loops, supporting one-click automatic mechanical gain tuning to eliminate low-frequency mechanical resonance without tedious manual parameter calibration. Three switchable control modes via parameter setup: analog speed control as primary mode for micro CNC feed axes, torque control for ultra-light tension winding and micro pressure holding processes, auxiliary pulse position control for simple fixed-length micro positioning tasks. Multi-stage embedded notch filters suppress mechanical oscillation during frequent high-speed acceleration and deceleration reciprocating motion of tiny axes. Built-in electronic gear function allows arbitrary gear ratio adjustment to match various miniature mechanical reduction structures without physical mechanical modification. Multiple homing modes are supported including dog-trigger homing and encoder Z-phase signal homing, with adjustable homing velocity and position offset parameters suitable for micro stroke movement. Short-duration triple overload torque output meets rapid acceleration requirements of ultra-small light-load CNC axes. Integrated self-diagnosis system automatically records fault codes and pre-alarm operating states; most minor faults support remote alarm reset without power cycling, while severe hardware faults require full power-off restart to clear alarm status. Internal integrated braking circuit realizes energy consumption braking during motor deceleration, and external braking resistors can be expanded for equipment with frequent high-speed reciprocating micro movement.

This servo drive is matched with early Yasnac analog CNC systems, applied to ultra-small micro feed axes of miniature precision lathes, micro grinders and desktop tiny machining centers. Secondary typical applications include micro textile filament winding axes, miniature electronic assembly rotary indexing tables, compact desktop automatic test positioning platforms, micro printing fine paper feeding registration axes, and ultra-light auxiliary motion axes of sorting conveyors. It is designed for rack plug-in installation inside sealed indoor electrical cabinets of machining workshops. Deployment in high-dust, corrosive gas, long-term high-temperature or water splashing environments is prohibited without fully sealed extra protective enclosures. As an EOL discontinued legacy model, it is only suitable for maintenance and spare part replacement of aging micro CNC and miniature automation equipment, and not recommended for new equipment development projects.

Before power-on installation, confirm three-phase power supply voltage matches the drive rated specification, completely separate power cables and analog signal cables with full shielding, and connect the shielding layer of encoder cables to the dedicated grounding terminal of the drive. After initial installation, complete universal CNC parameter initialization, run automatic gain tuning according to actual micro mechanical load characteristics, and adjust speed limit, torque upper limit and soft start-stop parameters to reduce micro mechanical impact on precision machine tools. Judge operating status through front panel LED indicators during daily operation: steady green light means normal servo operation, flashing red light displays fault alarm codes. Under standard workshop conditions, conduct routine maintenance every two months: clean the built-in cooling fan and ventilation ducts to remove dust blocking heat dissipation, re-tighten all wiring terminals, inspect encoder cable outer jackets for abrasion, and test the backup battery voltage of absolute encoders. When a fault occurs, record the fault code first, cut off three-phase main power after the motor completely stops, then troubleshoot wiring short circuits, mechanical jamming or encoder damage according to fault definitions. For long-term equipment shutdown, disconnect the main power supply; wait more than 30 minutes before re-powering to avoid short circuits caused by internal circuit condensation. Do not disassemble internal power modules and control boards without professional maintenance authorization; high-voltage residual charge remains inside after power cut, wait at least 10 minutes before opening the drive housing for inspection. Avoid frequent rapid power-on and power-off cycles within a short time to protect internal rectifier circuits and braking transistors. Replace the built-in cooling fan immediately once abnormal noise or slow rotation is detected to prevent overheat shutdown failures. Store spare servo drives in dry constant-temperature warehouses with moisture-proof packaging to avoid circuit board oxidation and encoder circuit malfunction.