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ABS Absolute Encoder
1. Concept
A high resolution and fast communication encoder is critical for any high performance servo system. DMM's development of magnetic sensor incremental and absolute encoders combine up to 16-bits high resolution with a ruggedized design ideal for all industrial and high precision applications. A state of the art sensor calculation algorithm ensures highest accuracy and reliability of position and speed data.

2. Features
  • Robust, rigid structure, outstanding ruggedness
  • Factory sensor zero-field calibration eliminates environmental electrical noise/magnetic field disturbances
  • Active sensor calibration maintains optimal performance, high angular absolute accuracy
  • Highly advanced sensor calculation algorithm decrease mounting tolerance requirement and increase operation consistency and reliability
  • Low profile design. Smallest 33mm diameter ABS-16-01 version for small servo motors
  • Self developed and manufactured realize low cost and quick leadtime
  • (ABS-16 models) Proprietary serial communication protocol achieves 4-wire communication between encoder and servo drive, greatly simplifying wiring and increase communication reliability
  • (ABS-16 models) 1.875MbPS communication speed including 8-bit CRC per data packet

3. Magnetic Sensor
Multiple high sensitivity magnetic sensors are placed radially around a two pole permanent magnet. An advanced mathematical algorithm is used to process the response from each sensor and a high resolution position data per motor revolution is generated.

Unique structural design and carefully engineered coordination between rotating magnet and sensor components eliminate disturbance from external magnetic field. Rotating magnetic component physically detached from stationary sensor component - non-contact sensor. Disturbance from external dust or water is non-existent.

4. High Level Specification
Many important design elements contribute to successful application in harsh industrial environments. The input +5VDC power from servo drive is filtered through two circuits to guarantee stable position data output from encoder. During operation, the encoder actively calibrates the sensor data and output data. This decrease mounting tolerance requirements and increase resistance to shock and vibration.

The active calibration also increase overall position accuracy. The non-linear measurements from the encoder is accurately maintained within 0.1degree.

The new ABS-16-00 absolute encoder uses a proprietary bi-directional serial bus interface with the servo drive. Only 4 wires are used to achieve communication (+5VDC, S+, S-, Gnd). The significance of the 8-bit CRC code per encoder data packet is obvious when designing highly advanced control systems. We have implemented a high ratio of CRC length to data packet length for highest data reliability.

5. Application Functionality
The same magnetic sensor and encoder construction is also used in our DSN series incremental encoders. The same advanced sensor calculation algorithm ensures reliable incremental pulses, high accuracy and less dependence on mounting tolerances. Non-contact sensor and ultra-low inertia magnet allows measurement speeds up to 30,000rpm*1. Programmable to run commutation to any number of motor poles and incremental resolution from 1,024 counts/turn to 20,000 counts/turn.

All standard DMM servo motors are factory mounted with a 16-bit resolution (65,536 counts/turn) absolute encoder. This allows precise measurement of position information and results in fast motor positioning and smoothness in speed and torque delivery.

6. Heritage
First Introduced Year - 1995 (ABS-14)
Major Revisions - 2014 (ABS-16)

Applicable Products

*1 Max. 2,048 counts/turn resolution scale at 30,000 min-1. Custom, ultra-low inertia, dual set screw rotary component required for speeds greater than 10,000min-1.
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