Magnetic linear encoder
Lika Electronic SME21 magnetic linear encoder
Contactless magnetic linear sensor head for use with Lika magnetic tape, giving up to 1 µm resolution with push-pull or line-driver incremental outputs for linear and angular measurement.
Key specifications
| Data / bus | push-pull (HTL), line driver (TTL/RS422) |
|---|---|
| Resolution (finest) | 1,000 nm |
| Resolution | 1 µm max. |
| Scale | Lika magnetic tape (MTI tape up to 100 m) |
Summarised in our own words from Lika Electronic s.r.l.'s published data; series maxima, individual models vary. Last checked 2026-10-30. Source 1 · Source 2
Notes on this data
SME11 (down to 0.5 µm, for linear and torque motors) is listed in the same range but was not opened.
Specify Motion is not affiliated with Lika Electronic s.r.l.. Lika Electronic and SME21 are used only to identify the product. Comparisons use published figures; always confirm against the current datasheet.
Typical applications
Alternatives that meet or exceed these figures
Engineers often come to us with a Lika Electronic part number and leave with an alternative that is easier to source, quicker to deliver or a better fit for the machine. These 3 series from our supply network are the closest match on published figures.
Absolute linear magnetic read head for LMSA scales, 1 µm resolution, up to 10 m/s, IP67.
View ALS21 →Incremental linear magnetic tape scale with freely configurable pole pitch and up to nine tracks, supplied on long reels.
View LMSI →Figures are the highest published for each series and are not always measured the same way. A higher figure is not automatically a better choice: mounting, duty cycle, feedback, connectors and approvals matter too. An engineer will check the fit against your application before recommending anything.
What a magnetic linear encoder is
A magnetic linear encoder reads position from a magnetised scale, usually a flexible tape or a stainless-steel-covered strip with alternating poles, using a readhead with Hall-effect or magnetoresistive sensors. The readhead outputs incremental quadrature or analogue signals, or absolute position from a coded track. The scale can be cut to length and bonded to the machine, making long axes economical. Magnetic linear encoders tolerate dust, oil and coolant better than open optical systems.
When engineers choose a magnetic linear encoder
Choose a magnetic linear encoder for robust position feedback on long axes in harsh environments, such as woodworking, metal processing, packaging and linear motors on general automation. It is affordable and easy to install. The trade-offs are resolution and accuracy, which are typically lower than optical scales, and sensitivity to strong magnetic fields or ferrous debris. For precision metrology, optical or enclosed scales suit better.
How to specify the Lika Electronic SME21
Send these with your enquiry and an engineer can confirm the right SME21 variant or an equivalent:
- Resolution and accuracy (µm)
- Measuring length (mm or m)
- Absolute or incremental output
- Interface: TTL, sin/cos, SSI, BiSS
- Ride height and alignment tolerances (mm)
- Maximum speed (m/s)
- Environment and IP code
Common mistakes to avoid
- Exceeding ride height tolerances during installation
- Exposing tape to strong magnetic fields or magnetic tools
- Ignoring thermal expansion of the tape and substrate
- Expecting optical-grade accuracy
Lika Electronic SME21: frequently asked questions
What is the Lika Electronic SME21?
Contactless magnetic linear sensor head for use with Lika magnetic tape, giving up to 1 µm resolution with push-pull or line-driver incremental outputs for linear and angular measurement. Published series figures include resolution (finest) 1,000 nm. It is made by Lika Electronic s.r.l.; Specify Motion can help source it or propose an equivalent.
Who makes the Lika Electronic SME21?
The Lika Electronic SME21 is made by Lika Electronic (Lika Electronic s.r.l.) and is listed here for engineers comparing options. Specify Motion is not affiliated with Lika Electronic s.r.l.; brand names are used only to identify the product.
What is the resolution (finest) of the Lika Electronic SME21?
The published series maximum resolution (finest) is 1,000 nm. Individual models and sizes in the SME21 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 Lika Electronic SME21?
Yes. On published figures, Bogen ALS21 and Bogen xMARS are the closest match from our supply network. An engineer confirms the fit against your application before recommending anything.
How accurate is a magnetic linear encoder?
Accuracy depends on the scale and readhead, but magnetic linear encoders are typically accurate to several micrometres or tens of micrometres per metre, with resolution down to around a micrometre. This suits general automation and woodworking. For sub-micrometre accuracy, optical scales are usually needed.
Can magnetic tape scales be cut to length?
Many magnetic tape scales are supplied on a reel and can be cut to the required length, then bonded to the machine with adhesive backing and a cover strip. This makes long axes simple and economical. Follow the manufacturer's handling guidance to avoid damaging the magnetisation.
Further reading: How to select a linear encoder · Magnetic vs capacitive vs optical encoders · Encoders and feedback
Other magnetic linear encoder series
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