Festo CPV E ASI-4E4A Series Brief Description page 21

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 power supplies which guarantee reliable electrical
isolation of the operating voltage as per IEC/DIN EN
60204−1. Consider also the general requirements for
PELV circuits in accordance with IEC/DIN EN 60204−1.
By the use of PELV circuits, protection against electric
shock (protection against direct and indirect contact) is
guaranteed in accordance with IEC/EN 60204−1 (Electri
cal equipment for machines, General requirements).
Festo CPV..−GE−ASI−4E4A−... 0802d English 21