Festo SBO***-Q Series, Manual

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3. Installation
3-5
Festo P.BE-SBO-Q-EN en 1602e
3.1.1 Selecting a power supply unit
Warning
Use only PELV (protective extra-low voltage) circuits as
per IEC/DIN EN60204-1 for the electric power supply.
Take into account also the general requirements for
PELV circuits as per IEC/DIN EN 60204-1.
Use only power units which guarantee reliable
electrical isolation of the operating voltage as per
IEC/DIN EN 60204-1.
Protection against electric shock (protection against direct
and indirect contact) is guaranteed in accordance with
IEC/DIN EN 60204-1 through the use of PELV circuits
(Electrical equipment of machines - General requirements).
Recommendation: Use a separate closed-loop power supply
unit which does not have to supply any other devices. You will
then achieve the greatest possible resistance to interference.
Simple 24 V transformers with rectifier and filter capacitor
achieve output voltages of 28 V or more at low loads.
Correct operation can only be guaranteed if the permitted
operating voltage range is not exceeded (
è
Technical data in
appendix A.4).