Festo CPX - Page 164

B. Parameters and data of the CPX terminal
B−10
Festo P.BE−CPX−SYS−EN en 0902e
System parameter: Fail safe (reaction to communication faults)
Function no. 4402
Description Determines the signal status which the outputs/valves are to assume in the
event of fieldbus communication faults, e.g. in the event of:
 Communication failure (fieldbus interruption, PLC/IPC failure)
 Communication stop.
In the following case, the channel−orientated Fail Safe settings (module para
meters Fault mode and Fault state) are reset automatically for safety reasons
in
order to avoid undesired signal states.
 When changing from Assume fault mode" to Reset all outputs" or to Hold
last state".
Bit Bits 0, 1
Values
Bit 10
00
Fail safe
Description
Reset all outputs (presetting)
[Fail safe]
[Reset outputs]
01 Hold last state (retain signal status) [Hold last state]
10 Assume fault mode [Assume fault mode]
Note The Fault mode status is set with the channel−specific module parameters.
Further information on this parameter can be found in section C.3.
Tab.B/5: Fail safe