Analysis of spindle data
SMU - Spindle Monitoring Unit

The spindle is the centrepiece of a CNC machine tool and is subjected to extreme loads due to high speeds and centrifugal forces. Monitoring parameters such as speed, acceleration, vibration and temperatures ensures the quality of the workpieces and the longevity of the spindle, tools and machine.

The SMU (Spindle Monitoring Unit) from VS Sensorik analyses encoder signals, calculates operating data from the motor spindle and transmits this information via a PROFINET bus connection. The SMU can communicate directly with the encoder allowing functions to be accessed and modified. This includes initiating self-calibration, setting target values, activating or deactivating AGC (Automatic Gain Control), and retrieving the electronic nameplate. Data can also be stored directly in the encoder via the SMU.

Spindle monitoring with the SMU requires the use of encoders equipped with a PuV interface, version 3.0 or higher.

Technical data

Core function of the SMU:  Features of the SMU:
  • Signal analysis Sin/Cos/Ref.
    Amplitude / Offset / Phase
  • Continuous signal monitoring
    for analog Sin/Cos encoders
  • Amplitude monitoring
    Threshold / Peak value
  • Interference-free communication
    with the encoder during operation
  • Acceleration monitoring
    Threshold / Peak value / Crash detection
  • Full access to encoder memory and commands
    via PROFINET bus interface
  • Gear monitorng
    Radial Run-out / Defects
  • Extended memory
    freely configurable, up to 20 kB block memory, 512 B
  • Operating data acquisitions
    Operating hours / Speeds / Crash events
  • Easy installation in control cabinet
    Top-hat rail, 24 V power supply