Coding Keys; Marking Elements; Electrical Structure; Potential Groups - WAGO 750 Series System Manual

System Features

3.1.6 Coding Keys

I/O modules of the 753 Series and the associated plug-in wiring interfaces can have cod-
ing keys to prevent incorrect insertion. The coding using small plastic pins and sockets
simplifies assignment of the wiring interface to the I/O module.
More information about this

3.1.7 Marking Elements

The system components can be provided with labeling elements:
• On head stations:
– Above the indicators
– If there is a power supply infeed, above the individual connections
• On I/O modules of the 750 and 753 Series:
– Above the indicators
• On some I/O modules of the 750 Series:
– Above the individual connections

3.2 Electrical Structure

3.2.1 Potential Groups

The I/O system is divided into the following potential groups.
• System Level
This potential group encompasses all the system-side electronics and among other
things, includes the system supply and the local bus signals.
• Field Level
This potential group contains the field-side power supply and I/O signals. The node
structure can be divided into different sections through the supply and segment mod-
ules. Different field potentials can be used in the individual sections.
• Fieldbus
This potential group contains the signals of the respective fieldbus interface. The volt-
age and current levels depend on the fieldbus standard used.
• Functional Ground
To discharge EMC interference, the system power supply, the field power supply and
the I/O signal inputs and outputs are capacitively coupled within the module to the
functional ground via the DIN-rail contacts.
22 System manual | Version: 3.0.2
topic:8 Inserting Coding Keys [} 48]
Serie 750, 753
Figure 10: DIN-Rail Contact (example)