In the transformation of automation drive systems or the development of new equipment, the selection and installation of servo motors directly determine the dynamic performance and long-term reliability of the equipment. The Beckhoff AM8000 and AM8500 series synchronous servo motors cover a wide range from extremely low torque (0.2 Nm) to high torque (129 Nm), with flange sizes ranging from 40 mm to 194 mm, and support for multiple feedback systems (Resolvers, OCT single/multi turn, Hiperface) as well as options such as holding brakes, shaft seals, and forced air cooling. This article is aimed at on-site engineers, systematically sorting out the model meaning, technical parameters, mechanical installation, electrical wiring, brake use, power derating, and common fault troubleshooting of AM8xxx motors, helping you quickly complete selection and deployment in replacing old motors (such as Woodward, Honeywell, and other discontinued models) or new projects.
Model interpretation and selection framework
The order number for AM8xxx motors follows a strict structure: AM8 t u v-w x y z-a 00 0. Taking AM8032-1G10-0000 as an example:
AM8: Synchronous servo motor product series.
t: Motor series -0 is the standard inertia, 5 is the high inertia (AM85xx).
u: Flange dimensions -1=40 mm, 2=58 mm, 3=72 mm, 4=87 mm, 5=104 mm, 6=142 mm, 7=194 mm.
v: Total length -1 to 4 represents different stack lengths.
w: Shaft end form -0=optical axis, 1=with keyway and half key, 2=with IP65 shaft seal ring optical axis, 3=with IP65 shaft seal ring and keyway.
x: Winding types - A... Z, commonly used B, C, D, E, etc.
y: Feedback System -0=Resolver (14 bits), 1=OCT Single Loop 18 bits, 2=OCT Multi Loop 18 bits, A=OCT Single Loop 23 bits, B=OCT Multi Loop 23 bits, G=OCT Single Loop 24 bits SIL2, H=OCT Multi Loop 24 bits SIL2, 3/4=Hiperface Single Loop/Multi Loop 18 bits.
z: Maintain braking -0=no braking, 1=24 V braking.
a: Version -0=Standard.
Core selection parameters: First, determine the flange size and length based on the load inertia ratio, required rated torque, and speed, then select the winding (which affects the rated current and speed), and finally select the feedback according to the accuracy requirements. For vertical axis or scenarios that require power-off locking, a hold brake must be selected, but it should be noted that the brake is only used for holding and is not suitable for dynamic braking.
Technical Parameters Essentials
Taking commonly used models as an example (data based on 40 ° C ambient temperature, winding temperature rise of 100K):
Model: Flange static torque M ₀ (Nm), static current I ₀ (A), maximum speed (rpm), rotor inertia (kgcm ²), braking holding torque (Nm)
AM8011 40 0.20 0.76 10000 0.03 0.6
AM8022 58 0.80 1.50 12000 0.26 2
AM8032 72 2.38 2.95 10000 0.85 2
AM8042 87 4.10 4.10 9000 1.98 9
AM8052 104 8.20 6.30 9000 4.09 9
AM8062 142 21.10 12.40 6000 20.0 20
AM8072 194 54.60 20.60 5000 92.2 70
Winding selection: Multiple windings can be provided for the same motor length (e.g. AM8022 has 21B, 21D, 22D, 22E, 23E, 23F). Low current windings (such as 21A) are suitable for 115V or 230V power supply, while high current windings (such as 23F) can achieve higher torque but require larger peak current. When selecting, the rated current of the driver should not be less than the electrostatic current I ₀ of the motor, and the peak current should not be less than I ₀ max (usually 5 times I ₀, and 3 times AM806x and above).
Temperature protection: All motors (except AM801x) are equipped with LPTC-600 temperature sensors (equivalent to KTY84-130). 120 ° C warning and 140 ° C shutdown must be configured in the servo drive, otherwise the motor may demagnetize due to overheating.

Key points of mechanical installation
3.1 Flange installation
Use internal hexagon screws that comply with DIN EN ISO 4762 strength grade 8.8. Tightening torque:
AM801x:M4 × 16 → 3.4 Nm
AM802x:M5 × 16 → 5.5 Nm
AM803x:M5 × 16 → 5.5 Nm
AM804x:M6 × 20 → 10 Nm
AM805x:M8 × 25 → 25 Nm
AM806x:M10 × 30 → 50 Nm
AM807x:M12 × 40 → 85 Nm
Attention: Do not apply impact to the motor shaft during installation. Impact can damage the optical encoder (OCT/Hiperface) and cause concentricity deviation. The coupling or pulley must be disassembled using a pulling tool, and striking is strictly prohibited.
3.2 Axle end load
The allowable radial force F ᵣ and axial force F ₐ on the motor shaft are related to the speed. When using pulleys or gears, the radial force application point should be as close to the flange surface as possible. Excessive axial force can shorten the bearing life and cause the brake to remain stuck. The Beckhoff official website provides a "load/force calculator" for quick verification.
3.3 Installation direction and sealing
The standard installation position is IM B5 (horizontal, flange installation). When installing IM V3 (axis vertically upward), liquid may accumulate on the flange surface and seep into the interior of the motor due to capillary action. Even with the optional shaft seal ring (IP65) and sealed air interface, it is still recommended to drain regularly. For situations with splashing water or high dust, models with radial shaft seals (w=2 or 3 in the model) and sealed air connections (w=4 or 5) must be selected.