USAFED-44CS2K is a discontinued heavy-duty permanent magnet AC servo motor belonging to Yaskawa classic F-series, specifically engineered for heavy-load vertical feed axes of CNC machining equipment and automated lifting machinery. This unit is configured with rear external forced air cooling fan, built-in DC24V power-off electromagnetic brake and side-cable outgoing terminal layout marked by suffix K, matched exclusively with original CACR-SR44 series servo amplifier without customized driver firmware modification. It delivers consistent high continuous torque and reliable holding performance for vertical mounting applications such as Z-axis of vertical machining center, heavy-duty CNC lathe vertical carriage and automated lifting stations, featuring standard UTOPH incremental encoder for high-precision closed-loop positioning control.

USAFED stands for Yaskawa fully-enclosed F-type CNC dedicated servo base series; numeral 44 represents 4.4kW rated power grade; character C denotes external rear fan forced cooling structure instead of natural air cooling; S indicates integrated internal DC24V fail-safe electromagnetic brake; digit 2 refers to standard solid straight output shaft with factory-standard keyway for coupling installation; terminal suffix K defines lateral side outlet structure for both power cable and encoder harness, different from conventional axial wire exit of CA/FA standard variants.

The motor is designed for three-phase AC 200V to 230V 50/60Hz industrial main power input. Its continuous rated output power reaches 4.4kW with rated continuous operating current of 30A and fixed rated rotational speed at 1500rpm; continuous rated torque is 28.4Nm while instantaneous peak overload torque can hit three times rated torque for heavy startup acceleration and sudden load impact absorption. Internal embedded electromagnetic brake is rated at DC24V excitation voltage, which releases the shaft upon power supply input and mechanically locks output shaft immediately once main power cuts off to prevent vertical axis free sliding drop.Equipped with original UTOPH-81AUS differential line driver incremental rotary encoder with universal pin assignment, the encoder is fully compatible with unmodified original CACR-SR44 servo pack without extra wiring or parameter rewrite. Stator winding adopts Class F insulation grade to guarantee stable dielectric performance under long-term full-load continuous cyclic operation, and built-in winding temperature sensing circuit feeds overheat fault signal to matched servo drive for overheat protection trigger.

The servo motor adopts totally closed housing construction with IP50 protection rating and relies on independent rear external cooling fan for forced heat dissipation, leading to longer overall axial dimension compared with natural convection cooled FA series non-fan motors. Output shaft is standard solid straight shaft machined with standard key slot for rigid connection with ball screw or speed reducer coupling, and the whole motor net weight is approximately 13.2kg due to additional built-in brake module and side terminal box structure.Standard flange mounting dimension follows Yaskawa F-series unified installation specification for direct equipment fixation without adapter modification. Rated operating ambient temperature ranges from 0°C up to +40°C, while permissible storage temperature spans -20°C to +70°C; applicable working relative humidity is maintained within 5%~80%RH under non-condensation working condition. When installation elevation exceeds 1000 meters above sea level, continuous rated loading shall be properly derated to avoid overheating caused by deteriorated heat dissipation efficiency at thin air condition. Working surroundings with corrosive gas, conductive dust accumulation or continuous liquid splashing are prohibited, and the unit can withstand standard industrial vibration within 10Hz~55Hz frequency range.

USAFED-44CS2K perfectly pairs with original Yaskawa CACR-SR44 series servo amplifier under factory default parameter setup without driver hardware or program modification. The matched servo system supports two mainstream command input modes including ±10V analog voltage speed instruction and differential pulse position command transmitted from upper CNC controller, which fulfills frequent forward-reverse reciprocating movement and micron-level repetitive positioning requirements of heavy machining and automated lifting equipment.For vertical installation application, internal built-in brake eliminates extra external mechanical anti-drop fixture requirement; the brake control terminal connects to DC24V auxiliary power supplied from servo unit to realize synchronous brake release with servo main power on and instant locking upon power failure. Complete closed-loop speed and position control can be activated after basic encoder parameter configuration on corresponding servo panel.

Multiple built-in protection circuits are integrated inside motor and matched servo drive system. Stator winding overheat detected by internal temperature sensor triggers servo overload stop protection to avoid winding burnout from long-hour overloading; encoder wire disconnection or poor contact will activate driver No.6 alarm code; continuous excessive load operation results in No.7 overload fault alert while winding short-circuit and abnormal overcurrent leads to No.1 overcurrent protection shutdown. Abnormal stall or open-circuit of rear cooling fan generates pre-warning signal on servo display for early maintenance arrangement before motor overheat damage occurs. Internal signal circuit is fitted with surge suppression components to strengthen anti-interference capability against industrial site instantaneous power surge and electromagnetic noise disturbance.

Direct field replacement requires identical USAFED-44CS2K original model; non-S brake variant or non-K standard axial outlet motors cannot be directly substituted due to different internal brake wiring and terminal box layout unless full driver parameter reset and wiring rearrangement are completed after replacement. Before disassembling for bearing inspection, encoder repair or cooling fan maintenance, users must fully cut off three-phase main power and wait minimum 15 minutes for servo internal DC bus capacitor complete discharge to eliminate residual high voltage for electric shock prevention.Routine periodic maintenance includes fastening power and encoder terminal screws every three months, refilling bearing lubricant grease after every 8000 cumulative operating hours and cleaning dust deposits on cooling fan blades every half year to maintain rated heat dissipation efficiency. Random alteration on internal encoder pin definition, brake coil wiring or stator winding connection will cause servo runaway movement and permanent driver fault locking.

This servo motor is primarily applied on vertical Z-axis feed drive of medium and heavy-duty vertical machining centers, vertical slide axis of heavy-duty CNC lathes, automatic heavy material lifting production lines and customized non-standard heavy-load automated equipment, especially suitable for vertical mounting working condition requiring power-off shaft holding and continuous high-torque cyclic operation with strict positioning accuracy demand.