Lenze DSD - Manual (Page 439)

Lenze · Drive Solution Designer · Manual · DMS 4.2 EN · 12/2013 · TD23
439
17 Restrictions of the drive dimensioning
17.24 Application of bearing current chokes
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17.24 Application of bearing current chokes
• Lenze servo motors of the MDFQA series already are equipped with insulated bearings and in-
sulated feedback systems. Like this, bearing currents are completely avoided.
• For the MCS and MCA servo motors, so far no necessity for insulated bearings or for the use of
bearing current chokes has been established by field observation.
• The MDXMA three-phase application motors imply the possibility of providing for insulated
bearings and insulated feedback systems from frame size 200 for an additional charge. Below
the frame size 200, up to now no necessity for insulated bearings or for the use of bearing cur-
rent chokes has been established by field observation.
This check additionally is to be carried out manually:
Under specific conditions it my be required to use bearing current chokes from a specific motor out-
put (approx. > 15 kW) for preventing premature bearing failures.
17.25 Improved motor control with temperature detection (KTY)
If the servo control mode (SC) is used, we recommend to use motors with a KTY thermal sensor.
If the temperature is detected via KTY, the motor control is able to evaluate the signal of the thermal
sensor. That way, the control properties are improved.
• The torque performance is independent of the motor temperature.
• The motor always provides the optimal torque.
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Note!
Only relevant for inverters > 15 kW!