ABB DCS 400, Manual

Page: 114 / 192

II K 5-14
Installation
24 Connection exam-
ple in accordance
with EMC
See figure 5.2 - 7.
25 Armature and
field cables with
screens for
“first environ-
ment”
See figure 5.2 - 7.
26 Armature and
field cables
without screens
for “second en-
vironment”
See figure 5.2 - 7.
27 Encoder inputs
and analogue
I/O at the PCB
See figure 5.2 - 7.
Remarks
28
Internal ground
connections
Additionally to the PE connections good HF connections to ground
must be realised with the aid of a mounting plate which has a well
conducting surface (sheet metal from zinc - plated steel for exam-
ple). This means, the housings of the line filter and of the converter
must be pressed directly to the mounting plate by at least four fix-
ing bolts, and the seating surfaces of the housings must be free
from non conducting coating. These ground connections are indi-
cated in the drawing at the top by the mass or chassis symbol:
The PE bar must be connected with the mounting plate by many
bolts, which are distributed along its whole length with equal dis-
tances.
29
Internal earth
connections
All devices are connected with the PE bar by the mounting plate
(and also by PE conductors), and the PE bar is earthed via the PE
conductor of the 3-phase power cable.
External earth
connections
The drive shall be earthed only by the earth conductor of the
line cable, see 29 . An additional local earthing, especially at the
motor, raises the level of the RF noise on the line cable.
Earth connec-
tions between
motor and
driven machine
The earth of a grounded machine must be connected to the earth
of the driving motor, in order to avoid floating potential.
Thermal motor
protection
It is recommended that the cable of thermal motor protection de-
vice is fed through an appropriate filter at the point of entry into cu-
bicle, in order to suppress EMC disturbances.