In short:AC servo motors and servo drives from other makers can replace many SIMOTICS S and SINAMICS S200, S210 and V90 axes, but equivalence depends on torque, speed, inertia, flange and shaft, feedback, supply, and above all how the drive integrates with your PLC over PROFINET or another fieldbus.
What Siemens makes in servo motion
Siemens AG supplies a complete industrial automation portfolio, and its motion range is designed to work with its SIMATIC controllers and TIA Portal engineering software. SIMOTICS and SINAMICS are trademarks of Siemens.
On the motor side, SIMOTICS S servo motors include the 1FK2, 1FT2, 1FK7, 1FT7, 1FL6 and 1FL2 lines, plus the 1FS2 for hygienic areas. On the drive side, SINAMICS S200 and S210 are single-axis servo drives, V90 is a basic servo drive, and S120 is the modular multi-axis system. Siemens’ own S200 package pairs the drive with a 1FL2 motor in PROFINET and pulse-train versions, up to 7 kW, commissioned through Startdrive in TIA Portal.
Why engineers look for a Siemens servo alternative
- Lead time, particularly when a machine build is waiting on a few axes.
- Budget, on simpler axes such as conveyors, indexing and format changes where a cost-optimised servo meets the requirement.
- Second source for machines sold into many markets.
- Different interface, for example a machine moving to EtherCAT, or a low-voltage DC axis on a mobile platform.
- Customer preference, where an end user specifies a different drive brand.
What to check before calling a servo motor or drive equivalent
Motor
- Rated and peak torque, and the torque-speed curve at your supply voltage.
- Rated and maximum speed.
- Rotor inertia and the resulting load-to-motor inertia ratio.
- Flange, pilot, shaft diameter and key, and overall length.
- Encoder type and resolution, single-turn or multi-turn absolute.
- Brake, IP rating and cooling.
Drive
- Supply voltage and phase, continuous and peak current.
- Fieldbus and control mode: PROFINET with PROFIdrive, EtherCAT, pulse train or analogue.
- PLC integration: GSDML, supported telegrams and motion technology objects.
- Safety functions such as STO, and any SIL or PL rating your risk assessment needs.
- Tuning tools, and who on your team will commission it.
- Cable lengths and whether the motor uses separate power and feedback cables or a single combined cable.
Our guides on selecting a servo motor, selecting a servo drive and servo vs stepper cover the sizing steps.
Servo alternatives in our supply network
Servo motors. The Kinco SMK series is a current-generation AC servo line from 40 to 180 mm frames, 50 W to 7.5 kW and up to 47.8 Nm rated. The Kinco SMH series covers a similar range up to 48 Nm. The Leadshine ELM1 / ELM2 motors come with 23-bit absolute encoders and IP65/IP67 sealing.
Servo drives. For PROFINET machines, the Leadshine EL7 platform has PROFINET, EtherCAT and Modbus/pulse variants from 400 W to 22 kW with STO, and the Kinco FD5P (PRO) drives run to 7.5 kW with RS485, EtherCAT or PROFINET. The Kinco JD2 drives suit CANopen or EtherCAT machines and accept a wide range of encoder protocols.
For low-voltage axes, see the servo drives hub and the servo and stepper motors hub.
How these comparisons are made
The table under this text compares each Siemens series we hold data for with the closest product from our supply network, on published figures only. “Equivalent” means a product that meets the stated specification for your application, confirmed by an engineer, not an identical product or a drop-in replacement in TIA Portal. Specify Motion is not affiliated with, authorised by or endorsed by Siemens, and no logos are used. Product names are used only to identify what is being compared.
For high-end S120 or 1FT motion, the right answer is sometimes to stay with Siemens. We will say so if it is.
Siemens series and the closest match from our supply network
Each row compares the highest published figures for the series. A match here is a starting point: an engineer confirms the fit for your load, duty, mounting and interface before recommending anything.
| Siemens series | Type | Closest match |
|---|---|---|
| SINAMICS S120 | Multi-axis servo drive | Kinco FDS Two-in-One Low-Voltage DC Servo Drive (FDS-AB/CB/LB-D) Same product type |
| SINAMICS S200 | AC servo drive | Leadshine EL7S / EL7 Series AC Servo Drives meets or exceeds the figures compared Meets or exceeds all 2 figures compared |
| SINAMICS S210 | AC servo drive | Leadshine EL7S / EL7 Series AC Servo Drives meets or exceeds the figures compared Meets or exceeds the figure compared |
| SINAMICS V90 | AC servo drive | Leadshine EL7S / EL7 Series AC Servo Drives meets or exceeds the figures compared Meets or exceeds the figure compared |
| SIMOTICS S-1FK2 | AC servo motor | Kinco SMK Series AC Servo Motors (SMK40S/60S/80S, SMK130G, SMK180G) meets or exceeds the figures compared Meets or exceeds all 2 figures compared |
| SIMOTICS S-1FK7 | AC servo motor | Kinco SMK Series AC Servo Motors (SMK40S/60S/80S, SMK130G, SMK180G) meets 1 of 2 figures Meets 1 of 2 figures compared |
| SIMOTICS S-1FL2 | AC servo motor | Kinco SMH Series AC Servo Motors (SMH40S-SMH180D) meets or exceeds the figures compared Meets or exceeds all 2 figures compared |
| SIMOTICS S-1FL6 | AC servo motor | Kinco SMK Series AC Servo Motors (SMK40S/60S/80S, SMK130G, SMK180G) meets or exceeds the figures compared Meets or exceeds all 2 figures compared |
| SIMOTICS S-1FS2 | Stainless servo motor | Kinco SMK Series AC Servo Motors (SMK40S/60S/80S, SMK130G, SMK180G) meets or exceeds the figures compared Meets or exceeds all 2 figures compared |
| SIMOTICS S-1FT2 | AC servo motor | Ask an engineer |
| SIMOTICS S-1FT7 | AC servo motor | Ask an engineer |
Specify Motion is not affiliated with Siemens AG. Brand and series names are used only to identify products. Comparisons use published figures; always confirm against the current datasheet.
Frequently asked questions
Can a non-Siemens servo drive work with a SIMATIC PLC?
Yes, many drives have PROFINET interfaces and supply a GSDML file for configuration. The practical question is how they are controlled: which PROFIdrive telegrams they support, whether they work with the PLC's motion technology objects, and how much commissioning moves out of TIA Portal into the drive maker's software. Check this before you compare price.
Can I keep my SIMOTICS motors and change the drive?
It is rarely worth it. Siemens servo motors use encoder systems designed around Siemens drives, and another drive may not read the encoder or the electronic rating plate. In most cases, an alternative is proposed as a matched motor and drive pair, with the mechanical interface checked so the motor fits the machine.
How do I compare servo motors between makers?
Compare rated and peak torque, rated and maximum speed, rotor inertia, flange size, shaft diameter and key, brake, encoder type and resolution, IP rating and cooling. Then check the torque-speed curve at your supply voltage, because two motors with the same rated power can deliver quite different torque at speed.
What should I send to get a Siemens equivalent proposed?
Send the motor and drive order numbers, the load, inertia and motion profile, supply voltage, fieldbus, the PLC model, safety functions in use such as STO, cable lengths and environment. If you have a sizing report from Siemens' tools, include it, as it shows the operating points the alternative must meet.
Sources
Figures are summarised from the sources above and from manufacturers' published data on the date shown. Always confirm against the current datasheet for your exact part.