I/O Terminal /
MOUNTING AND WIRING
Note:
During the design of a bus terminal block, the pin assignment of the individual Bus
Terminals must be taken account of, since some types (e.g. analog Bus Terminals or digital
4-channel Bus Terminals) do not or not fully loop through the power contacts. Power Feed
Terminals interrupt the power contacts and thus represent the start of a new supply rail.
3.1.4 PE Power Contact
The power contact labeled PE can be used as a protective earth. For safety reasons this contact
mates first when plugging together, and can ground short-circuit currents of up to 125 A.
WARNING!!
Note that, for reasons of electromagnetic compatibility, the PE contacts are
capacitatively coupled to the mounting rail. This may lead to incorrect results
during insulation testing or to damage on the terminal (e.g. disruptive discharge
to the PE line during insulation testing of a consumer with a nominal voltage of
230 V).
For insulation testing, disconnect the PE supply line at the Bus Coupler or the
Power Feed Terminal! In order to decouple further feed points for testing, these
Power Feed Terminals can be released and pulled at least 10 mm from the
group of terminals.
Note:
The PE power contact must not be used for other potentials!
3.1.5 Wiring
Up to eight connections enable the connection of solid or finely stranded cables to the Bus
Terminals. The terminals are implemented in spring force technology. Connect the cables as
follows:
1. Open a spring-loaded terminal by slightly pushing with a screwdriver or a rod into the square
opening above the terminal.
2. The wire can now be inserted into the round terminal opening without any force.
3. The terminal closes automatically when the pressure is released, holding the wire securely
and permanently.
Note
: Analog sensors and actors should always be connected with shielded, twisted
paired wires.
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