Series AI25 Absolute Encoders with BiSS Interface


Acuro Series AI25 Absolute Encoder with BiSS Interface

 AI25 BiSS Absolute Encoders
  Dynapar Brand Logo

Quick Specs...

  • Up to 17 Bit single-turn resolution
  • 4096 revolutions of multi-turn resolution
  • Short installation depth
  • Safety through self-diagnostics
  • Solid shaft and hollow shaft versions
  • -40° C to +100° C Operating temperature

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Overview Industry/Application Specifications Related Info  

Overview / Design Principle:

The ACURO AI25 absolute encoder is available in a single-turn or multi-turn version. Its multi-turn design is based on a reliable high-speed gear with optical scanning and the latest generation of OptoASIC technology.

Mechanical concept is based on a double ball bearing design, and is available as a solid-shaft or hollow-shaft version in common shaft diameters.

BiSS is a new, fully-digital and bi-directional sensor interface. It defines communication between one master and several slaves (sensors) in industrial control systems. BiSS manifests a new standard in technology and is available license-free. Due to its high performance, it constitutes an efficient alternative to the standard combination of data interface and analog sine/cosine incremental output.

BiSS needs only 6 wires and does not require any hardware for analog signals - and therefore, helps to reduce system costs.

Self-configuration allows "plug + play" and keeps the system in an operable condition even after a power failure. For detailed information on BiSS and support, please visit

BiSS Benefits:

  • All digital interface eliminates the costs of interpolation electronics
  • Offers transmission reliability through a 4-bit cyclic redundancy check (CRC)
  • Represents the only fully digital, open motor feedback interface for real-time applications

Features and Benefits:

  • Compact design to save valuable space
  • Low power consumption
  • Fast delivery of any model variant
  • Additional field-bus and point-to-point interfaces available

The Dynapar Advantage:

  • Innovative, high quality leading edge technology encoder products
  • Broad commercial - industrial grade product line
  • Customized built to order solutions available
  • Global Manufacturing & Service Support
  • Fast-Friendly Customer Service & Technical Support with Multi-Lingual Capabilities
  • Global Network of Authorized Resellers
  • Competitive Product Warranty:  2 Years 


Dynapar brand ACURO Absolute Encoders offer a modern full-feature design equipped with BiSS interface.

Standard Operating Characteristics
Single-turn Resolution: 10, 12, 13, 14, 17 Bit
Multi-turn Resolution: 12 bit (only available with 12, 13, 14, or 17 bit ST resolution)
Linearity: +/- 1/2 LSB
Absolute Accuracy: ± 0.01° mechanical (36 arc-sec.)
Repeatability: ± 0.002° mechanical (7.2 arc-sec.)
Code format: Binary, Gray, Gray Excess, parameterization through AcuroSoft
Parameterization: Resolution code type, sense of rotation, warning, alarm

Connection: Cable, M23 - 12-pole Conin connector, M12 - 8-pole connector
Supply voltage: 5 VDC -5%/+10% or 10-30 VDC
Intrinsic current consumption: 50 mA (ST), 100 mA (MT) not including output current
Output current: 60 mA per bit, short circuit protected
Frequency response: 500 kHz
Maximum cable length: 400 m
Control Inputs: Direction
Alarm output: Warning and Alarm bits
Status LED: Green = OK, Red = Alarm (IP64 only)
Preset Switch: Sets encoder to zero output at present mechanical position (IP64 only)

Shaft diameter: Shaft: 6 mm (Servo Mount), 10 mm (Clamping Mount), 3/8" (Square Flange Mount)
Hubshaft: 10 mm, 12 mm, 3/8", 1/2"
Maximum shaft load: 6 mm shaft: 13 lb axial, 24 lb radial
10 mm shaft: 24 lb axial, 35 lb radial
Maximum shaft speed: 10,000 RPM (continuous), 12,000 RPM (peak)
Starting torque: < 1.4 in-oz
Weight (approx.): 350 g ST, 400 g MT
Shaft tolerance (hubshaft only): +/- 1.5 mm axial, +/- 0.2 mm radial
Flange configurations: Square, Clamp, Servo, Hubshaft with flexible tether
Bearing life: 1 x 1010 revolutions at 35% full rated shaft load
1 x 109 revolutions at 75% full rated shaft load
1 x 108 revolutions at 100% full rated shaft load

Operating Temperature: -40 to 100° C
Storage Temperature: -40 to 100° C
Enclosure Rating: IP64 or IP67
Shock: 1,000 m/s2 (6 ms)
Vibration: 100 m/s2 (10 to 2,000 Hz)

Available Specifications:

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