Siemens SINAMICS S120 Manual page 330

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9.13 K50, Sensor Module Cabinet-Mounted SMC30
For encoders with a 5 V supply at X521/X531, the cable length is dependent on the encoder
current (this applies to cable cross-sections of 0.5 mm²):
Figure 9-24 Signal cable length as a function of the encoder current consumption
For encoders without Remote Sense the permissible cable length is restricted to 100 m
(reason: the voltage drop depends on the cable length and the encoder current).
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Cabinet Modules liquid cooled
Manual, 10/2015, A5E37067587A