Festo DNCKE S Serie Notice D'utilisation page 37

DNCKE−...−S / KEC−...−S
Use a one−way flow control valve type GRLZ−... or GRLA−... directly at the sup
S
ply port.
Activating the cylinder with clamping unit:
Select the control variant for your application.
S
The following example controllers meet at most the specified classification to
ISO 13849−1. If a higher performance level (PL) is required (by the result of a
risk analysis or by a corresponding C standard), additional control measures
will have to be taken. To fulfil the requirements for a PL in Cat.2 or higher, addi
tional testing and monitoring measures (DC level) are needed, for example, of
pressure, displacement, valve position.
Example of holding device
Ensuring against pressure failure
The piston rod is clamped even if there is a
pressure failure.
The controller for the specified safety
function has max. PLc/cat 1 to
ISO 13849−1.
When releasing the clamping unit, there is
movement due to the difference of the pis
ton areas.
Fig. 9
Festo DNCKE−...−S / KEC−...−S 1002a English
Approaching a clamping position
The clamping can be loosened if both cyl
inder chambers are pressurised (this is to
avoid a jerky movement when the piston
rod extends).
The controller for the specified safety
function has max. PLd/cat 3 to
ISO 13849−1.
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