Festo CPX-FB38 Electronic Manual page 109

3. Diagnosis
Festo P.BE−CPX−FB38−EN en 0804NH
Warning
Undesired activation of actuators!
An incorrect status of the valves and outputs can lead to
dangerous situations!
Make sure that valves and outputs are put into a safe
·
state when faults occur.
Check within the framework of your EMERGENCY STOP
·
concept and the fail safe setting to ascertain the
measures necessary for putting your machine or system
into a safe state.
Typical safety measures for safe system condition:
switching off the load voltage for the valves and output
modules in the secondary circuit of the power unit
switching off the compressed air supply for the valve
terminal.
Due to energy stored in the input circuitry of valve ter
minals, there may be a delayed reaction of the valves when
the load voltage is switched off.
Take this situation into account, for example by:
using an input signal in the controller for checking
whether the load voltage has been switched off
blocking the control signal for the valves by locking the
output signal with the input signal Load voltage".
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