VFD vs Servo Drive: Key Differences
A side-by-side comparison of VFD and servo drive motor type, feedback, dynamic response, overload rating, cost, and applications for industrial engineers.
- Part number
- 1FK7081-2AF71-1QA0
SIMOTICS SSiemens 1FK7081-2AF71-1QA0 SIMOTICS S 1FK7-CT 2.7 kW 12 Nm 3000 rpm Servo Motor
Siemens 1FK7-CT servo motor, 2.7 kW, 12 Nm, 3,000 rpm, IP64, no holding brake.
Description
About the 1FK7081-2AF71-1QA0
About the 1FK7081-2AF71-1QA0
The Siemens 1FK7081-2AF71-1QA0 is a SIMOTICS S 1FK7-CT synchronous servo motor rated 2.7 kW with 12 Nm standstill torque at 100K and a 3,000 rpm rated speed. It runs on a 600 V DC link, uses natural cooling, and carries an IP64 enclosure with an absolute 20-bit single-turn DRIVE-CLiQ encoder (AS20DQI). This variant ships without a holding brake.
Selection Notes
Without a holding brake, this 1FK7-CT variant fits horizontal axes where an external mechanical stop or the drive's controlled ramp-down covers the standstill condition. The 20.000 kgcm² rotor inertia and 1.35 ms mechanical time constant favor point-to-point moves that need fast direction reversals over high top speed. At 3,000 rpm rated speed the 12 Nm standstill torque holds up to roughly 3.8 kW at rated point, so size the drive's current limit around the 6.8 A rated current rather than the motor frame alone.
Applications
Typical use: pick-and-place and indexing axes on packaging and assembly lines, and any SINAMICS S120/S210 DRIVE-CLiQ axis where a compact 80 mm flange servo motor with 12 Nm standstill torque matches the load.
Specification
Full specification
Engineering data 10
| Rated speed (100 K) | 3,000 rpm |
|---|---|
| Number of poles | 8 |
| Rated torque (100 K) | 8.7 Nm |
| Rated current | 6.8 A |
| Static torque (60 K) | 10.00 Nm |
| Static torque (100 K) | 12.00 Nm |
| Stall current (60 K) | 7.10 A |
| Stall current (100 K) | 8.70 A |
| Moment of inertia | 20.000 kgcm² |
| Efficiency | 93.0 % |
Physical constants 9
| Torque constant | 1.38 Nm/A |
|---|---|
| Voltage constant at 20º C | 88.5 V/1000*min¯¹ |
| Winding resistance at 20º C | 0.42 Ω |
| Rotating field inductance | 7.7 mH |
| Electrical time constant | 18.20 ms |
| Mechanical time constant | 1.35 ms |
| Thermal time constant | 45 min |
| Shaft torsional stiffness | 109,000 Nm/rad |
| Net weight of the motor | 12.9 kg Permanent-magnet synchronous |
Mechanical data 16
| Motor type | motor Compact |
|---|---|
| Shaft height | 80 |
| Cooling | Natural cooling |
| Radial runout tolerance | 0.050 mm |
| Concentricity tolerance | 0.10 mm |
| Axial runout tolerance | 0.10 mm |
| Vibration severity grade | Grade A |
| Connector size | M23 |
| Degree of protection | IP64 |
| Design acc. to Code I | IM B5 (IM V1, IM V3) |
| Temperature monitoring | Pt1000 temperature sensor |
| Electrical connectors | Connectors for signals and power rotatable |
| Color of the housing | Standard (Anthracite RAL 7016) |
| Holding brake | without holding brake |
| Shaft end | Feather key |
| Encoder system | Encoder AS20DQI: absolute encoder single-turn 20 bits |
Show all 54 specifications ↓ Show less ↑19 more values in Identification, Optimum operating point, Limiting data, Recommended Motor Module, Logistics.
Identification 5
| Part number | 1FK7081-2AF71-1QA0 |
|---|---|
| Brand | Siemens |
| Condition | New, factory sealed |
| Source | Siemens and its authorised distributors |
| Warranty | Manufacturer warranty |
Optimum operating point 2
| Optimum speed | 3,000 rpm |
|---|---|
| Optimum power | 2.8 kW |
Limiting data 4
| Max. permissible speed (mech.) | 6,000 rpm |
|---|---|
| Max. permissible speed (inverter) | 6,000 rpm |
| Maximum torque | 37.0 Nm |
| Maximum current | 30.0 A |
Recommended Motor Module 4
| Rated inverter current | 9A |
|---|---|
| Maximum inverter current | 27 A |
| Maximum torque | 34.10 Nm |
| Page 1 of 1 | Generated Sun Nov 1 02:21:08 CET 2026 |
Logistics 4
| Shipping weight | 13.901 kg |
|---|---|
| Ships from | Türkiye |
| Dispatch | — |
| Stock | On request |
Source: manufacturer data · Last verified: 01 Nov 2026
Documents
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Quick answers
Questions about the 1FK7081-2AF71-1QA0
What is the rated current of 1FK7081-2AF71-1QA0?
The rated current of 1FK7081-2AF71-1QA0 is 6.8 A.
What motor power is 1FK7081-2AF71-1QA0 rated for?
The rated motor power of 1FK7081-2AF71-1QA0 is 2.7 kW.
What is the HS code of 1FK7081-2AF71-1QA0 for customs?
The tariff (HS) code on file for 1FK7081-2AF71-1QA0 is 85015220.
Where does 1FK7081-2AF71-1QA0 ship from, and how fast?
1FK7081-2AF71-1QA0 ships from Türkiye. Shipping calculated at checkout · import duties and taxes paid on arrival.
Guides
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Customer reviews
Series
Siemens SIMOTICS S
- Brand
- Siemens
- Series
- SIMOTICS S
