Power Electronics SD750FR, Hardware And Installation Manual

Page: 46 / 80

SD750FR POWER ELECTRONICS
44
POWER CONNECTION
EN
Ground connection
Before connecting the power conductors, make sure that the chassis of the drive and the adjoining
cabinets are connected to ground through the dedicated (PE) terminals. These are situated at both sides
of the bottom metal walls of the drive and they are labeled with the earth symbol. Check section “Power
Terminals”.
The motor chassis ground must be con
nected to the drive. In other words, connect the motor’s ground
conductor to the PE protection terminal of the drive and not to the installation’s ground. It is recommended
that the section of the motor ground conductor (PE) has at least the same cross section as the motor
power cables sections (U, V, W). Additionally, it must be installed following the recommendations
indicated in section “Power connection and wiring”.
The line ground must be connected to the drive. In other words, connect the installation
’s transformer
ground conductor to the PE terminal of the drive and not to the installation’s ground. We recommend that
the cross section of the transformer’s ground conductor (PE) complies with the IEC 61800-5-1 standard
(10mm² for copper cables and 16mm² for aluminium cables). Additionally, it should be installed following
the recommendations indicated in section “Power connection and wiring”.
When connecting the earth, ensure that all connected cable terminals are properly tight and protected
from mechanical forces. The tightening torque in case of M10 PE terminals is 40Nm.
CAUTION
For safety reasons, the earth resistance of the installation must be measured. This must be
established before the first start up of the plant and with the drive disconnected.
It is the responsibility of the installer to provide the appropriate number, type and section of cables
for the ground conductor
in accordance with the characteristics of the equipment used and the plant to
minimize ground resistance, which must comply with local and national regulations.