Absolute Linear Magnetic Encoder — OTV AMG Series
The OTV AMG is a true absolute magnetic linear encoder system engineered for high-performance motion control applications. It delivers non-contact, wear-free absolute position feedback for linear motion axes in demanding industrial environments.
- Industry-leading 82,000 mm measurement length
- 1 μm resolution, ≤ ±2.5 μm repeatability
- Five protocols: BiSS-C, SSI, Tamagawa, Modbus-RTU, Panasonic
- IP67 rated — no homing, no batteries, no backup memory
What Is the OTV AMG Absolute Linear Magnetic Encoder?
The measurement standard is a magnetic scale (MSA50 series) consisting of a stainless steel substrate bonded with an elastomeric ferrite layer. The ferrite layer carries two magnetically encoded tracks.
1. Anatomy of the AMG Encoder System
Magnetic Scale (MSA50)
A stainless steel carrier bonded with an elastomeric ferrite layer, encoded with two parallel data tracks — an incremental track (5 mm pole pitch) and an absolute track (14-bit PRBS).
Sensor Readhead
An advanced readhead combining an AMR (Anisotropic Magnetoresistance) sensor for high-speed incremental interpolation and a Hall sensor array for absolute position decoding.
MCU Signal Processing
An internal MCU fuses both data streams using proprietary algorithms to output the final absolute position via BiSS-C, SSI, Tamagawa, Modbus-RTU, or Panasonic.
2. Measuring Principle
Incremental Track
A 5 mm pole-pitch track with alternating N/S poles for high-speed incremental interpolation via an AMR sensor.
Absolute Track
A 14-bit pseudo-random binary sequence (PRBS) track for absolute position decoding via a Hall sensor array — no reference marks or homing sequence required.
Chemical Resistance
The elastomeric ferrite layer is inherently resistant to oils, coolants, and chemicals commonly present on the factory floor.
Why Linear Motion Systems Choose the AMG Series
Four reasons the AMG is the feedback solution of choice for high-performance linear axes.
1. Absolute Position on Startup
Valid absolute position within 400 ms of power-up — no homing, no batteries, no backup memory. Ideal for safe startups and multi-axis machines.
2. Industry-Leading Measurement Range
Maximum measurement length of 82,000 mm — a single continuous scale with no segment switching or stitching errors, even on large gantry systems.
3. High-Speed, Low-Latency Operation
Linear velocity up to 5 m/s with position update time under 6 μs — designed for high-bandwidth servo control loops.
4. Rugged IP67 Construction
Aluminum housing fully sealed against dust and water, rated for 100% relative humidity, with operation from −20°C to +80°C.
Key Features of the OTV AMG Series
Engineered for precision, durability, and seamless industrial integration.
True Absolute Measurement
Genuine dual-track absolute encoding delivers valid position within 400 ms of power-up — no battery backup, no reference marks, no homing sequence.
Industry-Leading 82 m Range
The longest absolute magnetic linear encoder range available — 82,000 mm on a single continuous scale with no segment switching.
1 μm Resolution
1 μm resolution with repeatability ≤ ±2.5 μm and system accuracy ≤ 50 μm (module and mounting dependent).
Multi-Protocol Interface
Five digital protocols from one hardware platform: BiSS-C, SSI, Tamagawa, Modbus-RTU, and Panasonic — selected at time of order.
Rugged IP67 Construction
Anodized aluminum housing, fully sealed against dust and water immersion, with high-flex TPU drag-chain cable rated for 20 million cycles.
Smart LED Diagnostics
A multi-color LED reports normal operation, over-temperature warning, signal loss, misalignment, and absolute-track errors for rapid field troubleshooting.
OTV AMG Encoder System
OTV AMG Specifications
Complete specifications for the AMG encoder readhead and MSA50 magnetic scale.
System Performance
| Parameter | Specification |
|---|---|
| Resolution | 1 μm |
| Repeatability (Unidirectional) | ≤ ±2.5 μm @ 1 μm resolution, 1.2 mm gap |
| System Accuracy | ≤ 50 μm (module and mounting dependent) |
| Position Update Time | < 6 μs (during active communication) |
| Absolute Position Startup Time | < 400 ms after power-up |
| Maximum Linear Velocity | 5 m/s |
| Sensing Gap (Nominal) | 1.2 ± 0.3 mm |
| Sensing Gap (Allowable Range) | 0.2 – 2.0 mm |
Electrical
| Parameter | Specification |
|---|---|
| Supply Voltage | 5 VDC ± 5% |
| Operating Current (No Load) | < 200 mA @ 25°C ambient |
| Output Type | Differential RS422 / Serial RS485 (protocol-dependent) |
| Output Load Current | ±40 mA per channel |
| Interface — BiSS-C (RS422) | Max clock: 5 MHz |
| Interface — SSI (RS422) | Max clock: 0.7 MHz |
| Interface — Tamagawa (RS485) | Baud: 2.5 Mbps, 24-bit position |
| Interface — Modbus-RTU (RS485) | Max baud: 256K |
| ESD Protection (RS422) | HBM ±20 kV |
| ESD Protection (RS485) | HBM ±15 kV |
Mechanical
| Parameter | Specification |
|---|---|
| Dimensions (L × W × H) | 93 × 23 × 11 mm |
| Mounting Hole Spacing | 86 mm (M3 clearance holes) |
| Housing Material | Anodized Aluminum |
| Weight | Approx. 30 g (without cable) |
| Connector Options | DB9 Male / DB15 Male / SCSI-26 Male / SM-6P / Bare Wire (NC) |
| Cable Type | TPU, high-flex, dual-shielded, 8-core, twisted-pair, drag-chain rated |
Environmental
| Parameter | Specification |
|---|---|
| Operating Temperature | −20°C to +80°C |
| Storage Temperature | −20°C to +105°C |
| Protection Class | IP67 (IEC 60529) |
| Relative Humidity | 0 – 100% (condensing) |
| Max External Magnetic Field (Operating) | 0.5 mT |
| Vibration (Operating) | 10 – 2000 Hz, 100 m/s² (IEC 60068-2-6) |
| Shock (Operating) | 300 m/s², 11 ms (IEC 60068-2-27) |
Magnetic Scale — MSA50 Series
| Parameter | Specification |
|---|---|
| Scale Series | MSA50 |
| Incremental Pole Pitch | 5.0 mm |
| Absolute Encoding | 14-bit PRBS |
| Effective Measurement Length | Up to 82,000 mm (custom cut to order) |
| Scale Width | 10 mm |
| Total Thickness | 1.4 mm (including adhesive) |
| Substrate | Stainless steel, non-magnetic |
| Magnetic Layer | Elastomeric ferrite, chemically resistant |
| Adhesive | High-bond acrylic, pre-applied |
| Minimum Handling Bend Radius | > 60 mm |
| Operating Temperature | −20°C to +80°C |
| External Field Tolerance | < 0.5 mT for normal operation; > 25 mT causes irreversible damage |
Typical Applications
The AMG series serves a broad range of precision linear motion applications across demanding industries.
Linear Motors & Direct Drive
Voice coil actuators, planar motors, iron-core and ironless linear stages.
Semiconductor Equipment
Wafer handling, pick-and-place, inspection and metrology stages.
Lithium Battery Manufacturing
Electrode winding, stacking, slitting, calendaring, and cell assembly.
CNC & Precision Machine Tools
Linear axes on grinding machines, milling centers, and lathes.
Medical & Laboratory Automation
Precision positioning stages, scanning systems, liquid handling.
Large-Format Processing
Gantry systems, laser cutting, waterjet cutting, large-area inspection (up to 82 m).
Common Questions About the OTV AMG Series
What is an absolute magnetic linear encoder?
It is a position sensor that reads a dual-track magnetic scale using a non-contact readhead to output a unique absolute position along a linear axis — no homing, batteries, or optical components required.
What measurement length does the AMG support?
Up to 82,000 mm (82 m) on a single continuous scale, custom cut to order. This is the longest range available for an absolute magnetic linear encoder.
Which communication protocols does the AMG output?
Five protocols from one hardware platform: BiSS-C and SSI (RS422), plus Tamagawa, Modbus-RTU, and Panasonic (RS485). The protocol is selected at time of order.
What sensing gap should I maintain?
The nominal sensing gap is 1.2 ± 0.3 mm, with an allowable range of 0.2 – 2.0 mm. A 1.2 mm spacer gauge is included for installation.
What is the operating temperature range?
The encoder operates from −20°C to +80°C and is rated IP67, with 0–100% condensing humidity and tolerance to external magnetic fields up to 0.5 mT.
How is the MSA50 scale installed?
The scale uses a pre-applied high-bond acrylic adhesive — simply peel the liner and press onto a clean surface. A spacer gauge and printed directional markings ensure correct orientation.
Ready to Spec Your Linear Encoder?
Tell us your measurement length, protocol, and accuracy requirements. Our engineering team will recommend the optimal AMG configuration — scale length, connector, and cable — for your application.
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