ABB AC500 V3 Hardware Manual page 920

System assembly, construction and connection
Overall information (valid for complete AC500 product family) > EMC-conforming assembly and construction
● Rout signal cables and data cables separately from the power cables.
–
–
● Lay signal and data cables close to earthed surfaces.
2.4.4.3 Cable shields
● Use only shielded data cables. The shield should be grounded at both ends.
A cable shield only grounded at one end can only protect from capacitively coupled interfer-
ence and low-frequency disturbances (50 Hz hum).
● Avoid parasitic currents flowing through the cable shields.
This can be done by installing current-carrying equipotential bondings.
● Use only cables with braided shields.
Foil shields are not robust enough, cannot be contacted well and have poor HF properties.
● Use only metallic or [metal]-plated plugs for shielded data cables.
● Use only shielded cables for analog signals.
For small signals ground the shield only at one end.
● Ground the cable shield directly with a clip when entering the switchgear cabinet.
Do not cut the shield until the cable reaches the module connected.
2.4.4.4 Switchgear cabinet
Connections The connections between the switchgear cabinet, the mounting plates, the PE bar and the
shield bar must have a low impedance.
Grounding Ground the switchgear cabinet doors with short and highly flexible conductors.
Illumination Only use filament lamps (bulbs) or fluorescent tubes with interference suppression.
For supplying Use the mains socket which is located inside the switchgear cabinet.
the PC
Ä Chapter 2.6.2.1 "Switchgear cabinet assembly" on page 976
2.4.4.5 Reference potential
● Provide a uniform reference potential in the entire installation and ground all electrical
appliances if possible.
● Route your grounding conductors in a star configuration so that no ground loops can occur.
920
Separate cable ducts or cable bundles.
The distance should be 20 cm or greater.
The connection between the PE bar and the shield bar must have a low impe-
dance.
According to DNV GL mounting in a seperate metall cabinet is required for:
– SM560-S-FD-1
– CI521-MODTCP
– CI522-MODTCP
3ADR010278, 3, en_US 2022/01/31