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System Description
eddyNCDT SGS 4701
2.3
Structure of the Measuring System
The eddyNCDT series SGS 4701 is developed for recording the thermal and mechanical expansion of high-
speed milling spindles. This enables the active compensation of the axial spindle expansion via e. g. a CNC
machine tool.
The SGS 4701 consists of a sensor, a sensor cable and a controller which can be factory calibrated for
ferromagnetic or non-ferromagnetic measurement objects. Miniature sensors enable it to be installed directly
in the spindle, where the measurements take place, typically on the labyrinth-ring of the spindle. As well as
measuring linear expansion, the temperature of the sensor is also detected and output. The compact control-
ler can be installed on the spindle housing via a flange or directly in the spindle.
Fig. 1 Typical installation with
measurement on the labyrinth ring
Fig. 2 Measuring system consisting
of sensor and controller
Due to its compact size, the measurement technology (paired electronics and sensor) is fully integrated into
the spindle head.
