Watt Drive L2000 Series, Руководство пользователя, Страница: 7 / 52

Manual
Page 7 / 52
Observe the following provisions for an electromagnetically compatible setup of your
drive system:
1. As user you must ensure that the HF impedance between frequency inverter, filter and ground is
as small as possible.
•
Take care it that the connections are metallic and have the largest possible areas (zink-plated
mounting plates)
2. Conductor loops act like antennas, especially when they encompass large areas. Consequently:
•
Avoid unnecessary conductor loops
•
Avoid parallel arrangement of „clean“ and interference-prone conductors
3. Lay the motor cable and all analog and digital control lines shielded.
•
You should allow the effective shield area of these lines to remain as large as possible; i.e.,
do not move the shield further away than absolutely necessary.
•
With compact systems, if for example the frequency inverter is communicating with the
steering unit, in the same control cabinet connected at the same PE-potential, the screen of
control lines should be put on, on both sides with PE. With branch systems, if for example the
communicating steering unit is not in the same control cabinet and there is a distance
between the systems, we recommend to put on the screen of control lines only on the side of
the frequency inverter. If it is possible, direct in the cable entry section of the steering unit.
The screen of Motor cabels always must be put on, on both sides with PE.
•
The large area contact between shield and PE-potential you can realise with a metal PG
screw connection or a metallic mounting clip.
•
Use only copper mesh cable (CY) with 85% coverage
•
The shielding should not be interrupted at any point in the cable. If the use of reactors,
contactors, terminals or safety switches in the motor output is necessary, the unshielded
section should be kept as small as possible.
•
Some motors have a rubber gasket between terminal box and motor housing. Very often, the
terminal boxes, and particularly the threads for the metal PG screw connections, are painted.
Make sure there is always a good metallic connection between the shielding of the motor
cable, the metal PG screw connection, the terminal box and the motor housing, and carefully
remove this paint if necessary.
4. Very frequently, interference is coupled in through installation cables. This influence you can
minimize:
•
Lay interfering cables separately, a minimum of 0.25 m from cables susceptible to
interference.
•
A particularly critical point is laying cables parallel over larger distances. If two cables
intersect, the interference is smallest if they intersect at an angle of 90°. Cables susceptible to
interference should therefore only intersect motor cables, intermediate circuit cables, or the
wiring of a rheostat at right angles and never be laid parallel to them over larger distances.
5. The distance between an interference source and an interference sink (interference-threatened
device) essentially determines the effects of the emitted interference on the interference sink.
•
You should use only interference-free devices and maintain a minimum distance of 0.25 m
from the drive.
6. Safety measures
•
Ensure that the protective conductor terminal (PE) of the filter is properly connected with the
protective conductor terminal of the frequency inverter. An HF ground connection via metal
contact between the housings of the filter and the frequency inverter, or solely via cable
shield, is not permitted
as protective conductor connection. The filter must be solidly and
permanently connected with the ground potential so as to preclude the danger of electric
shock upon touching the filter if a fault occurs. You can achieve this by connecting it with a
grounding conductor of at least 10 mm² or connecting a second grounding conductor,
connected with a separate grounding terminal, parallel to the protective conductor (the cross
section of each single protective conductor terminal must be designed for the required
nominal load).