3.4 Connecting the AS-interface bus and the load voltage
Please note
The sensor power supply for the inputs is provided via
the AS-interface bus. Voltage suppply of the outputs
via the AS-Interface bus is only possible with type
CPV...-GE-ASI-4E4A.Type CPV...-...-Z must always be
supplied with 24 V via the load voltage connection.
The AS-Interface has an integrated watchdog function
which resets the outputs if there is a bus communica-
tion failure.
Warning
Use only power units which guarantee reliable isolation
of the operating voltages as per IEC 742/EN 60742/
VDE 0551 with at least 4 kV isolation resistance (Pro-
tected Extra Low Voltage PELV). Switch power packs are
permitted, providing they guarantee reliable isolation
in accordance with EN 60950/VDE 0805.
Please note
By the use of PELV power units, protection against electric
shock (protection against direct and indirect contact) is
guaranteed in accordance with EN 60204-1/IEC 204.
Safety transformers with the adjacent symbol must be
used for supplying PELV networks. The valve terminals
must be earthed to ensure that they function correctly
(e.g. EMC).
Festo CPV..-GE-ASI-4E4A-... 0112c English
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