8.1.3
Electrical isolation
In the modules of the CPX-AP-I automation system, there is potential separation between the internal
electronics and
–
the network interfaces of the interfaces,
–
the system communication,
–
the load supply PL.
Information on the potential separations of the inputs and outputs of the modules
è
Technical data of the product-specific documentation
8.2
Functional earth FE
NOTICE!
Malfunction due to electromagnetic interference.
Depending on the substrate of the mounting surface, the modules must be connected to the function-
al earth with low impedance.
The general rule is:
•
Remove paint, corrosion and anodised layers.
•
Earthing cables should be as short as possible.
•
Screws, slot nuts, profiles etc. must have a high electrical conductivity.
For installation on conductive substrates:
•
Establish a low impedance connection between the module and conductive substrate as well as
between the conductive substrate and functional earth.
•
Establish equipotential bonding between different system components on which the modules are
mounted.
•
Avoid interference voltages on the conductive substrate.
For installation on an insulated substrate:
•
Establish a low impedance connection between the module and functional earth via an earthing
cable.
•
Use an earthing cable with a nominal cross section of 4 … 6 mm
2
.
•
Use a suitable cable lug according to DIN 46234, DIN 46225, DIN 46211.
8.3
Connecting the lines
WARNING!
Risk of injury due to electric shock.
•
For the electric power supply, use SELV or PELV circuits that guarantee a reliable electric discon-
nection from the mains network.
•
Observe IEC 60204-1/EN 60204-1.
1. Switch off the power supply.
2. Observe the tightening torque of the cables (e.g. hook spanner with torque adjustment).
3. Seal unused connections with cover caps.
Installation
19
Festo — CPX-AP — 2019-06
