Bosch Rexroth IndraDrive HMV01.1E-W0030, Project Planning Manual, Page: 114 / 132

13-14
Appendix Rexroth IndraDrive
DOK-INDRV*-HMV-*******-PR01-EN-P
13.5 Fault Current Protective Device
DANGER
High electrical voltage! Danger to life, severe
bodily harm by electric shock!
⇒
A residual-current-operated protective device (RCD)
must not be used on electric drives! Indirect contact
must be prevented by other means, for example, by
an overcurrent protective device.
•
In clocked drive controllers, capacitive leakage currents primarily flow
to earth. The extent of this current depends on
•
the number of drive controllers used,
•
the length of the motor power cable and
•
the grounding conditions at the installation.
•
If measures are taken to improve the electromagnetic compatibility
(EMC) of the installation (mains filters, shielded lines, etc.), then the
current leakage is inevitably also increased. In order to avoid faulty
releases when inductive loads and capacitance (interference
suppression filters, transformers, contactors, magnetic valves) are
switched on, it is necessary to provide an isolating transformer in the
mains supply line ahead of the power supply unit of the drive system.
The over current protective device must be matched to the impedance
of the fault loop so that a shutdown is effected if a fault occurs. The
star point of the secondary winding must be connected to the
protective circuit of the installation.
13.6 Earth Leakage Monitor
Earth leakage monitors are often used in IT mains. Spurious releases can
occur when operating electronic equipment.
Experience has shown that electronic drive controllers can only be
operated on systems with earth leakage monitors if an isolating
transformer is situated ahead of the supply unit for the drive system. The
star point of the isolating transformer and the PE connection of the power
supply unit must be applied to the same potential.