High-Precision Absolute Inductive Encoders for Demanding Motion Control
- Non-contact · Bearingless · Hollow-shaft design
- ±0.0014° accuracy · 15-23 bit resolution
- 54 standard models · Non-contact sensing
Choose an inductive encoder series around the application
OTV-INE: compact rotary feedback
Explore the OTV-INE series for bearingless hollow-shaft integration. Compare bore, outside diameter, thickness and speed in the INE table.
OTV-INEC: protected construction
Use the INEC table on this page when an enclosed IP67-rated option is required. Confirm connector and installation conditions.
OTV-INEM: rotary tables
Compare rotary table encoders by stator and rotor dimensions, absolute accuracy, repeatability and controller interface.
OTV-INED: hollow-bore geometries
Compare hollow inductive encoder models by stator bore and rotor dimensions, resolution and model-specific accuracy.
Resolution, accuracy, speed, temperature range and protection level belong to the selected model. The highest values across the collection do not describe a single encoder. Use the series tables and drawings to define the complete ordering configuration.
What Is an Inductive Encoder?
An inductive encoder uses electromagnetic induction and wireless energy transfer to measure absolute angular position — without optical discs, glass gratings, or permanent magnets. The stator wirelessly powers the rotor, which returns a position signal through electromagnetic field modulation.
Unlike optical encoders that fail in dust, oil, or vibration, inductive encoders deliver maintenance-free absolute positioning even in the harshest conditions.
- 1Wireless Power TransferStator coil energizes → power transmitted to rotor via electromagnetic coupling
- 2Dual-Track Position SensingRotor modulates the magnetic field → stator reads absolute angle via dual code tracks
- 3Digital OutputOnboard ASIC converts to SSi / BiSS-C / RS-422 / RS-485 / ABZ in real-time
Inductive vs Optical vs Magnetic Encoders
| Selection factor | Inductive encoder | Optical encoder | Magnetic encoder |
|---|---|---|---|
| Sensing principle | Electromagnetic coupling with a patterned target | Optical reading of a coded scale or disc | Magnetic field sensing with a matched target |
| Contamination | No optical path; assess enclosure and material exposure | Maintain the specified optical path and protection | No optical path; assess ferrous debris and target protection |
| Accuracy and resolution | Compare separate accuracy and resolution specifications under equivalent mounting, calibration and temperature conditions. | ||
| Mechanical package | Bearingless and enclosed arrangements exist. Compare actual bore, thickness, mounting gap and runout limits. | ||
| Environment and interface | Temperature, IP rating, electrical interface and electromagnetic performance are model-specific. | ||
OTV-INE Series — Precision
Ultra-thin profile (3.6–8 mm), highest resolution (up to 22-bit), best accuracy (up to ±0.006°), highest speed (up to 8,000 rpm). IP40. Ideal for space-constrained precision motion control — robotics, aerospace, gimbals, and medical devices.
OTV-INEC Series — Rugged
IP67-rated for harsh environments, wider operating temperature (-40°C to +85°C), wider supply voltage (5–30 V). Aluminum alloy housing. Ideal for industrial automation, servo motors, and demanding environmental conditions.
OTV-INEM Series — High Precision
Single-turn absolute inductive encoders for rotary tables and precision rotary stages. Compare three hollow-bore models by ring dimensions, 23-bit resolution, accuracy and controller interface.
OTV-INED Series — Hollow-Bore Absolute
Absolute rotary position feedback in a hollow-bore inductive format. Compare 29 models by stator and rotor dimensions, 11–23-bit resolution, listed accuracy and RS485 / SPI interface options.
OTV-INE Series — 13 Standard Models
All models: Non-contact · Hollow-shaft · FR-4 material · Single-turn absolute · 5-24V DC · IP40
| Model | OD × ID × T (mm) | Weight | Resolution | Accuracy | Max Speed | Rotor Inertia |
|---|---|---|---|---|---|---|
| INE-014 | 14.8 × 2 × 3.6 | 2 g | 15-17 bit | ±0.03° | 6000 rpm | 0.006 kg-mm² |
| INE-016 | 16.8 × 2 × 3.6 | 2.5 g | 15-17 bit | ±0.025° | 6000 rpm | 0.008 kg-mm² |
| INE-018 | 18.8 × 2 × 3.6 | 3 g | 15-17 bit | ±0.02° | 6000 rpm | 0.01 kg-mm² |
| INE-020 | 20 × 4 × 6.5 | 4 g | 15-17 bit | ±0.05° | 4000 rpm | 0.01 kg-mm² |
| INE-040 | 40 × 10 × 7.8 | 10 g | 17-18 bit | ±0.015° | 6000 rpm | 0.4 kg-mm² |
| INE-052 | 52 × 17.7 × 7.6 | 13 g | 18-20 bit | ±0.01° | 8000 rpm | 1.18 kg-mm² |
| INE-060 | 60 × 25 × 7.6 | 18 g | 18-20 bit | ±0.008° | 8000 rpm | 2.43 kg-mm² |
| INE-080 | 80 × 35 × 8 | 30 g | 18-20 bit | ±0.008° | 8000 rpm | 8.6 kg-mm² |
| INE-100 | 100 × 48 × 8 | 40 g | 19-21 bit | ±0.006° | 6000 rpm | 19.7 kg-mm² |
| INE-120 | 120 × 70 × 8 | 50 g | 19-21 bit | ±0.006° | 6000 rpm | 40 kg-mm² |
| INE-140 | 140 × 90 × 8 | 75 g | 19-21 bit | ±0.006° | 6000 rpm | 99 kg-mm² |
| INE-180 | 180 × 120 × 8 | 120 g | 20-22 bit | ±0.006° | 4000 rpm | 239.2 kg-mm² |
| INE-247 | 247 × 172 × 8 | 180 g | 20-22 bit | ±0.006° | 4000 rpm | 795.6 kg-mm² |
Download Full Product Datasheet (PDF)
Includes mechanical drawings, electrical specs, ordering codes, and installation guide for all 13 models.
OTV-INEC Series — 9 Standard Models
All models: Non-contact · Hollow-shaft · Aluminum alloy + FR-4 · Single-turn absolute · 5-30V DC · IP67
| Model | OD × ID × T (mm) | Weight | Resolution | Accuracy | Max Speed | Rotor Inertia |
|---|---|---|---|---|---|---|
| INEC-016 | 16 × 4 × 9 | 5 g | 15-17 bit | ±0.05° | 4000 rpm | 0.005 kg-mm² |
| INEC-025 | 25 × 6 × 7 | 10 g | 15-17 bit | ±0.025° | 4000 rpm | 0.042 kg-mm² |
| INEC-025P | 25 × 6 × 7 | 10 g | 15-17 bit | ±0.025° | 4000 rpm | 0.042 kg-mm² |
| INEC-037 | 37 × 10 × 8 | 15 g | 16-18 bit | ±0.02° | 4000 rpm | 0.197 kg-mm² |
| INEC-040 | 40 × 10 × 10 | 25 g | 16-18 bit | ±0.02° | 4000 rpm | 0.197 kg-mm² |
| INEC-058 | 58 × 20 × 10 | 40 g | 17-19 bit | ±0.015° | 4000 rpm | 0.684 kg-mm² |
| INEC-070 | 70 × 30 × 10 | 55 g | 17-19 bit | ±0.015° | 3000 rpm | 3.338 kg-mm² |
| INEC-130 | 130 × 90 × 10 | 200 g | 18-20 bit | ±0.01° | 1500 rpm | — |
| INEC-170 | 170 × 120 × 11.5 | 260 g | 18-20 bit | ±0.01° | 1500 rpm | 219.237 kg-mm² |
OTV-INEM Series – Rotary Table Models
Single-turn absolute position | 23-bit resolution |+/-5 arcsec absolute accuracy | +/-1 arcsec repeatability | RS485 / BiSS-C / SSI interfaces
| Model | Stator ID / OD | Stator thickness | Rotor ID / OD | Rotor thickness | Turns | Resolution |
|---|---|---|---|---|---|---|
| INEM-035 | 44.8 / 90 mm | 4.5 mm | 35 / 80.2 mm | 4.1 mm | Single-turn | 23-bit |
| INEM-036 | 51 / 106 mm | 5.5 mm | 36 / 90 mm | 7.1 mm | Single-turn | 23-bit |
| INEM-058 | 72 / 128 mm | 5.5 mm | 58.75 / 113 mm | 7.1 mm | Single-turn | 23-bit |
Use the dimensional drawings and confirm the selected interface, mounting envelope and complete tolerances before finalizing your design. View the Rotary Table Encoders selection page.
Technical Advantages
Why Engineers Choose OTV Inductive Encoders
Bearingless & Coupling-Free
No internal bearings, no mechanical couplings. The rotor mounts directly on the shaft. The stator fixes to the housing. Installation gap: 0.6mm ±0.1mm. Zero friction, zero wear.
Model-Specific Interface Options
SSi (0.5-5MHz) · BiSS-C (up to 10MHz with CRC) · RS-422 full-duplex · RS-485 half-duplex · Differential ABZ with Z-phase. Availability depends on the selected model and ordering configuration.
Check Environmental Ratings
Operates from -30 to +100°C. Resistant to shock (100g/11ms), vibration (20g 10-2000Hz), electromagnetic interference, and 0-99% humidity. Confirm exposure conditions and the specified protection of the selected assembly.
Ultra-Thin Profile
As thin as 4mm — a compact option for the selected model. Fits space-constrained robot joints, gimbals, and actuator housings where conventional encoders simply won’t fit.
Model-Specific Accuracy
Up to ±0.006° static error with 22-bit resolution. Repeatability: ±2 LSB. Compare accuracy under equivalent mounting, calibration and temperature conditions.
Power-On Absolute Position
True single-turn absolute output — knows its angle the instant power is applied. No homing routine, no backup battery, no reference mark search. Simplifies system startup.
Where OTV Inductive Encoders Excel
Collaborative Robots
Ultra-thin hollow-shaft design for joint torque sensors and motor feedback. Validate the installed encoder after shock or collision events.
Surgical & Medical Robots
Consider non-contact position feedback for tool and joint motion. Sterilization compatibility, cleanliness and medical-system requirements need application-specific qualification.
Aerospace & Defense
Radar pedestals, satellite antenna gimbals, EO/IR turrets. Vacuum, radiation and extreme-temperature requirements need separate qualification for the selected model.
AGV & Mobile Robots
Steering angle feedback for automated guided vehicles. Evaluate feedback performance in the installed motor and electromagnetic environment.
Industrial Automation
Servo motor feedback, rotary tables, packaging machinery. Compare mechanical fit, interface and environmental protection when replacing an optical encoder.
Semiconductor & Optoelectronics
Wafer handling robots, pick-and-place, optical alignment stages. Confirm cleanliness, vacuum compatibility and stage-level positioning requirements separately.
Complete Your Motion Sensing Solution
Beyond inductive encoders, OTV also manufactures high-precision magnetic encoders and encoder magnetic rings — a full portfolio for your sensing needs.
OME Series
Single-turn absolute magnetic encoder with 17-20 bit resolution, ±0.1° accuracy, 28.5mm ultra-compact form factor. SSi, BiSS-C, UART, SPI, ABZ protocols supported.
- 17-20 bit
- ±0.1° accuracy
- 8mm thin
- SSi / BiSS-C
- 6000 rpm
Precision Magnetic Rings
Single-track and dual-track magnetic encoder rings for use with magnetic encoders. Custom OD/ID/thickness, multi-pole magnetization, FR-4 substrate. Designed for OME series and third-party magnetic sensors.
- Single & Dual Track
- Custom Design
- Rubber+Metal
- Multi-Pole
- Low Inertia
- OEM Available
Common Questions About Inductive Encoders
Need a Custom Sensing Solution?
Every application is unique. OTV Precision Sensing delivers more than standard products — we engineer tailored encoder solutions and provide one-stop procurement to simplify your supply chain.
Custom Encoder Development
Need a specific OD/ID, resolution, protocol, or form factor? Our engineering team modifies standard designs or builds from scratch to your exact specifications.
One-Stop Procurement
Beyond encoders: magnetic rings, cables, connectors, mounting hardware, and accessories. We consolidate your BOM into a single order with one invoice and one shipment.
Dedicated Project Support
From concept to production. Feasibility review, rapid prototyping, NPI support, and ongoing quality management. Your assigned engineer stays with you throughout.
Tell us your requirements — we’ll respond with a solution within 24 hours.