Magnetic encoder
Renishaw RLS AksIM-4
Off-axis absolute magnetic ring encoder for through-hole rotary axes, including large-diameter rings. Non-contact with optional self-calibration.
Key specifications
| Outer diameter | 53–150 mm |
|---|---|
| Resolution (max) | 21 bit |
| Interface | BiSS C |
Summarised in our own words from Renishaw plc's published data; series maxima, individual models vary. Last checked 2026-10-29. Source 1 · Source 2 · Source 3 · Source 4
Notes on this data
Presented on renishaw.com magnetic encoders page as an RLS product; figures from rls.si. Big-ring version 115/150 mm OD, 20/21 bit; HIPERFACE DSL version 53/80 mm OD, up to 20 bit, accuracy up to ±0.005°; dual concentric version 19+19 bit. Operating -40 to +105 °C. Supply 4.5-5.5 V.
Specify Motion is not affiliated with Renishaw plc. Renishaw and RLS AksIM-4 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 Renishaw 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.
Harsh-environment hollow-shaft Electric Encoder with higher shock/vibration tolerance; tested to MIL-STD-810.
| Published maximum | RLS AksIM-4 | VLP |
|---|---|---|
| Resolution | 21 bit | 23 bit meets or exceeds |
Ultra-thin single-turn hollow-shaft capacitive encoder for general robotics and automation, with push-button calibration.
| Published maximum | RLS AksIM-4 | VLX |
|---|---|---|
| Resolution | 21 bit | 23 bit meets or exceeds |
Extreme-temperature hollow-shaft encoder rated from -55 C to +125 C for aerospace.
| Published maximum | RLS AksIM-4 | VLT |
|---|---|---|
| Resolution | 21 bit | 23 bit meets or exceeds |
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.
Other magnetic encoder series
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