Reflex function block: Fault Signaling
(Original Document)
About us
Role
This function is used to indicate a fault, with acknowledgement and clearing.
Structure
The table below shows the block's different interfaces.
Name
Meaning
Illustration
Def
Fault input.
Acq
Acknowledgement input
Eff
Clear input
x
Block's physical output.
x Aux
Output inactive for this block.
Operation
This table describes the different operating phases of the Fault Signaling function.
Phase
Description
1
If the Def status is at the high status, the x output oscillates for period 2 x t1i.
2
On the rising edge of input Acq:
  • if the fault persists, the output changes to 1,
  • if the fault disappears, the output oscillates for period 2 x t2i.
3
On the rising edge of the Eff input, the x output changes to 0.
Note: Should the fault still remain, the cycle begins again in phase.
Note: Output x flashes when a fault occurs:
  • t1i flashes rapidly: fault present and unacknowledged by Acq,
  • t2i flashes slowly: fault not present and acknowledged by Acq,
  • lit up: fault present and acknowledged by Acq,
  • out: last fault cleared by the Eff input after acknowledgement.
Illustration
The illustration below shows the trend diagram of the Fault Signaling function with t1i < t2i.