UGFMED-B9MMG11 DC MINERTIA SERVO MOTOR PRODUCT SPECIFICATION

UGFMED-B9MMG11 belongs to Yaskawa classic F-series Minertia coreless DC servo motor lineup, a discontinued high-precision low-inertia direct current servo unit originally designed for high-response precision automation and precision instrument drive scenarios. This motor adopts unique cup-shaped coreless rotor electromagnetic structure without iron core inside winding, featuring ultra-low rotor inertia, minimal cogging torque and ultra-smooth low-speed rotation performance, completely natural air cooling structure without external cooling fan. The suffix MMG11 stands for factory OEM customized incremental encoder specification with exclusive pin definition, dedicated rear connector wiring layout and fixed cable configuration different from standard general models. Equipped with built-in DC electromagnetic power-off holding brake marked by prefix B, this variant is optimized for vertical load installation requiring power failure anti-fall locking protection and high-frequency intermittent start-stop positioning control.

UGFMED is base series identifier for coreless Minertia DC servo motor; B denotes built-in DC operated fail-safe electromagnetic brake structure; numeral 9 stands for fixed frame size and rated power grade of this model; MMG represents customized encoder type and exclusive wiring specification; final two-digit number 11 is factory internal variant code defining default wire length, terminal arrangement and encoder pulse resolution setting.

This coreless DC servo motor is configured for rated armature DC working voltage of 144V standard industrial DC power supply system, designed to match Yaskawa legacy DC servo amplifier dedicated drive units. Its rated continuous output power reaches 0.9kW level, nominal rated running armature current is around 7.2A under full-load steady operation condition, standard rated rotating speed is fixed at 1750rpm, and continuous rated output torque maintains stable rated value for continuous cyclic load operation; instantaneous peak overload torque can reach up to 3.5 times rated torque to cope with abrupt acceleration startup and short-time impact load demands. The integrated DC brake coil runs on independent 24VDC auxiliary control power, shaft releases mechanically when brake coil gets energized and locks output shaft instantly once auxiliary power is disconnected to prevent vertical machinery free falling under unexpected power outage. The customized MMG11 incremental rotary encoder adopts differential line drive signal output following exclusive factory pin assignment rule, directly pluggable with matched original servo driver without rewiring or parameter modification. Internal stator winding complies with Class F insulation grade, embedded built-in temperature detection element feeds overheat fault signal to paired servo controller to activate automatic overload stop protection and avoid winding burnout under long-term overloading. Internal wiring cavity installs surge absorption components to suppress industrial field impulse voltage and surrounding inverter electromagnetic interference effectively.

The whole motor housing adopts fully enclosed construction with IP54 ingress protection rating and relies entirely on shell natural convection heat dissipation without auxiliary fan assembly. Front drive end is standard solid output shaft with integrated flat keyway for rigid connection with miniature precision reducer, ball screw and timing belt transmission components; owing to rear-end embedded brake module layout, overall axial length is longer than non-brake same frame coreless servo variants, and complete unit net weight is approximately 4.1kg with unified standard flange mounting dimension for direct equipment rack installation without extra adapter fixture.Permitted continuous operation ambient temperature scope ranges from 0°C to +40°C; spare part storage environmental temperature spans from -20°C up to +70°C; applicable working relative humidity keeps 5%RH~80%RH under non-condensing working condition to prevent dew induced internal circuit short circuit. When installation altitude exceeds 1000 meters above sea level, users need to derate continuous running load properly to compensate reduced natural cooling efficiency under thin atmospheric environment. The motor can withstand regular industrial vibration within 10Hz~55Hz frequency range; working sites containing corrosive gas, continuous liquid splash and heavy conductive dust accumulation are forbidden to prolong service life of front bearing, brake friction plate and internal winding components.

UGFMED-B9MMG11 is originally paired with Yaskawa old-generation dedicated DC servo drive modules, supporting two mainstream external command input modes including ±10VDC analog voltage speed command and differential pulse position instruction sent from upper-level PLC or miniature CNC host controller. The matched servo control system supports seamless switching among position closed-loop control, speed closed-loop control and torque closed-loop control according to different technological process requirements. Benefiting from built-in power-off brake structure, vertical installed equipment no longer needs extra external mechanical locking device for gravity anti-drop protection. As configured incremental feedback encoder is adopted, complete mechanical origin homing operation must be implemented after full system power cut before formal equipment startup to recover accurate mechanical zero position for subsequent precision positioning movement.

Cooperating with matched servo amplifier, the motor realizes comprehensive multi-level safety protection mechanism. Winding over-temperature signal triggers servo overload shutdown to protect internal coreless winding against thermal damage; MMG11 customized encoder cable open circuit or poor contact will trigger independent encoder fault alarm displayed on servo panel; internal winding short-circuit and abnormal overcurrent input will activate driver hardware overcurrent protection and immediate main power cutoff; brake coil open or short circuit fault outputs corresponding auxiliary warning prompt on matched drive terminal. All internal signal feedback circuits are fitted with noise suppression components to filter complex on-site electromagnetic interference and secure stable position feedback signal transmission.

Field maintenance replacement must adopt identical original UGFMED-B9MMG11 spare motor; non-brake variant or non-MMG customized encoder specification motors cannot realize direct substitution unless full connector rewiring and complete servo parameter reset work are finished after replacement. Before disassembling motor for bearing inspection, brake maintenance and encoder overhaul, operators shall fully cut off main DC armature power and 24VDC brake auxiliary power, then wait no less than 15 minutes for full discharge of servo internal DC bus capacitance to eliminate residual high voltage and prevent electric shock accidents. Regular maintenance items include tightening rear connector fixing screws every three months, replenishing high temperature resistant bearing lubricating grease after accumulated 8000 continuous working hours and cleaning casing accumulated dust semi-annually to retain original natural heat dissipation capacity. Random modification to MMG11 defined encoder pinout and internal brake wiring will lead to out-of-control motor runaway and permanent driver fault locking.

This coreless low-inertia DC servo motor is widely used for precision feed axes of miniature high-precision bench processing equipment, indexing positioning platform of small precision parts automated assembly line, micro drive of optical inspection testing equipment and compact precision packaging automation machinery, especially suitable for vertical installation occasions featuring frequent start-stop motion, high dynamic response requirement and strict power-off anti-drop positioning constraint.