AC servo motor
Festo EMMT-AS / EMMT-EC AC servo motor
Festo's servo motor range in 40 to 190 mm flanges, matched to the CMMT drives with one-cable connection; series maximum 183.3 Nm peak torque, 8.6 kW rated power and battery-free multi-turn absolute encoders.
Key specifications
| Ingress protection | IP40/IP21 shaft without seal; IP65 with shaft seal; IP67 housing |
|---|---|
| Temperature | -40–40 °C |
| Rated torque (max) | 82.4 Nm |
| Peak torque (max) | 183.3 Nm |
| Speed (max) | 16,000 rpm |
| Power (max) | 8,629 W |
| Frame sizes | 40, 60, 80, 100, 150, 190 |
| Supply | 48 V DC (EMMT-EC-40), 325 V DC and 680 V DC variants |
| Feedback | single-turn absolute 16-19 bit; battery-free multi-turn absolute 17-19 bit; optional EnDat safety encoder |
| Resolution (max) | 19 bit |
| Brake | optional 24 V DC holding brake |
Summarised in our own words from Festo SE & Co. KG's published data; series maxima, individual models vary. Last checked 2026-10-30. Source 1
Notes on this data
Temperature -15 to +40 C for 150/190 flanges; derating to +80 C. Festo states the holding brake is not a safety brake.
Specify Motion is not affiliated with Festo SE & Co. KG. Festo and EMMT-AS / EMMT-EC are used only to identify the product. Comparisons use published figures; always confirm against the current datasheet.
Festo EMMT-AS / EMMT-EC model codes
Published model codes in the EMMT-AS / EMMT-EC range, with key figures from the manufacturer's data. Search this page for your part number, or send it to us for availability or an equivalent.
| Model code | Winding | Nominal torque (Nm) | Peak torque (Nm) | Nominal speed (rpm) |
|---|---|---|---|---|
| EMMT-AS-40-S | LS | 0.21 | 0.83 | 7000 |
| EMMT-AS-40-M | LS | 0.32 | 1.41 | 7000 |
| EMMT-AS-60-S | HS / LS | 0.64 / 0.6 | 1.6 | 3000 |
| EMMT-AS-60-M | HS / LS | 1.1 / 1.0 | 3.4 | 3000 |
| EMMT-AS-60-L | HS / LS | 1.4 / 1.3 | 5.6 | 3000 |
| EMMT-AS-80-S | HS / LS | 1.3 | 2.8 | 3000 |
| EMMT-AS-80-M | HS / LS | 2.2 | 6.4 | 3000 |
| EMMT-AS-80-L | HS / LS | 2.9 | 9.9 | 3000 |
| EMMT-AS-80-H | HS | 3.4 | 13.5 | 3000 |
| EMMT-AS-100-S | HS | — | 13.7 | 2700 |
| EMMT-AS-100-M | HS | — | 22.4 | 2700 |
| EMMT-AS-100-L | HS | — | 30.5 | 2700 |
| EMMT-AS-100-H | HS | — | 38.7 | 2700 |
| EMMT-AS-150-M | HS / HV | 27.1 / 13.5 | 64 / 60 | 1500 / 3500 |
| EMMT-AS-150-L | HS / HT | 29 / 39.7 | 87 / 86 | 2100 / 1000 |
| EMMT-AS-190-M | HS | 59.1 | 118.3 | 1200 |
| EMMT-AS-190-L | HT | 82.4 | 183.3 | 1000 |
Typical applications
Engineer support
Speak to our engineers about your project
Our experienced engineers are on hand, ready to help with your project. Whether you need the Festo EMMT-AS / EMMT-EC itself, help sourcing it, or a modified or custom design built around your load, speed and space, tell us what the machine has to do and we'll come back with the right option.
- Help sourcing EMMT-AS / EMMT-EC and spares for installed machines
- Modified and custom designs when a catalogue part doesn't fit
- Complete axis: motor, drive, gearing and feedback matched together
What an AC servo motor is
An AC servo motor is a permanent-magnet synchronous motor designed for closed-loop control of position, speed and torque. A wound stator is driven by a servo drive with sinusoidal three-phase current, while magnets on the rotor follow the rotating field. A high-resolution encoder or resolver on the shaft feeds position back to the drive, which adjusts current many thousands of times a second. The result is precise, dynamic motion with high peak torque, typically about three times the continuous rating for short periods.
When engineers choose an AC servo motor
Choose an AC servo for machine axes needing fast, accurate motion under varying loads, such as packaging, robotics, machine tools and printing. Compared with steppers, servos keep torque at high speed and cannot silently lose position. The trade-offs are cost and set-up: a servo needs a matched drive, feedback and tuning. For simple, low-speed indexing with a steady load, a stepper may be cheaper. For very low speeds and high torque, a gearbox or direct-drive motor may be needed.
How to specify the Festo EMMT-AS / EMMT-EC
Send these with your enquiry and an engineer can confirm the right EMMT-AS / EMMT-EC variant or an equivalent:
- Continuous and peak torque (Nm)
- Rated and maximum speed (rpm)
- Load inertia and inertia ratio
- Supply voltage: 230 V single-phase or 400 V three-phase
- Feedback: incremental or absolute encoder, resolution (bits)
- Holding brake, IP code and shaft options
- Flange size and mounting (mm)
Common mistakes to avoid
- Sizing on peak torque without checking RMS torque over the cycle
- Ignoring load-to-motor inertia ratio, which makes tuning hard
- Forgetting the brake is for holding, not dynamic stopping
- Using a motor and drive pair that the supplier has not matched
Festo EMMT-AS / EMMT-EC: frequently asked questions
What is the Festo EMMT-AS / EMMT-EC?
Festo's servo motor range in 40 to 190 mm flanges, matched to the CMMT drives with one-cable connection; series maximum 183.3 Nm peak torque, 8.6 kW rated power and battery-free multi-turn absolute encoders. Published series figures include temperature -40 °C, temperature 40 °C, rated torque 82.4 Nm, peak torque 183.3 Nm. It is made by Festo SE & Co. KG; Specify Motion can help source it or propose an equivalent.
Who makes the Festo EMMT-AS / EMMT-EC?
The Festo EMMT-AS / EMMT-EC is made by Festo (Festo SE & Co. KG) and is listed here for engineers comparing options. Specify Motion is not affiliated with Festo SE & Co. KG; brand names are used only to identify the product.
What model codes are in the Festo EMMT-AS / EMMT-EC range?
The EMMT-AS / EMMT-EC range includes EMMT-AS-40-S, EMMT-AS-40-M, EMMT-AS-60-S, EMMT-AS-60-M, EMMT-AS-60-L, EMMT-AS-80-S, EMMT-AS-80-M, EMMT-AS-80-L and 9 more. The table on this page lists each published model code with its key figures. Send us the code you use, or the one you need to replace, and our engineers will confirm availability, lead time or the closest equivalent.
What is the temperature of the Festo EMMT-AS / EMMT-EC?
The published series minimum temperature is -40 °C. Individual models and sizes in the EMMT-AS / EMMT-EC range vary, so check the exact variant against your duty cycle, mounting and environment, or ask our engineers to confirm the right size for you.
Is there an alternative to the Festo EMMT-AS / EMMT-EC?
Yes. Our engineers can propose an equivalent built around your load, speed and environment. An engineer confirms the fit against your application before recommending anything.
What is the inertia ratio in servo sizing?
The inertia ratio compares the load inertia reflected to the motor shaft with the motor's rotor inertia. High ratios make the axis harder to tune and slower to settle. Many engineers aim for below about 10:1, and lower for highly dynamic axes, using a gearbox to reduce reflected inertia where needed.
Do AC servo motors need an absolute encoder?
Not always. Incremental encoders need a homing routine after power-up, which is acceptable on many machines. Absolute encoders know their position at power-on, avoiding homing, which saves time and suits robots and multi-axis machines. Multi-turn absolute encoders track turns even when power is off.
Further reading: How to select a servo motor · Servo vs stepper · Servo and stepper motors
Other ac servo motor series
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Engineer support
Our engineers are ready to help with your project
Tell us about your project and how you use the Festo EMMT-AS / EMMT-EC: the load, speed, duty and environment. An experienced engineer will review it and reply, normally within one working day.
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