Beckhoff KL2819, Документация

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Interference-free Bus Terminals
KL2819 14 Version: 1.1.0
External wiring
The following requirements are to be ensured by the system manufacturer and must be incorporated into the
user documentation.
• Protection class IP54
The terminals must be installed in IP54 control cabinets to ensure the necessary protection class IP54.
• Power supply unit
The standard terminals must be supplied with 24 V by an SELV/PELV power supply unit with an output
voltage limit U
max
of 60 V in the event of a fault.
• Prevention of feedback
Feedback can be prevented through different measures. These are described below. In addition to
mandatory requirements there are also optional requirements, of which only one needs to be selected.
◦ No switching of loads with a separate power supply
Loads that have their own power supply must not be switched by standard terminals, since in this
case feedback via the load cannot be ruled out.
Fig. 5: Negative example – active load
◦ The control of an STO input of a frequency converter could serve here as a negative example .
Exceptions to the general requirement are allowed only if the manufacturer of the connected load
guarantees that feedback to the control input cannot occur. This can be achieved, for example,
through adherence to load-specific standards.
◦ Option 1: Ground feedback and all-pole disconnection
The ground connection of the connected load must be fed back to the safely switched ground.