Reflex function block: Detection of underspeed
(Original Document)
About us
Role
This function is used to halt an action, after a start phase t1i (masking), if the time elapsing between two consecutive pulses is higher than t2i.
Structure
The table below shows the block's different interfaces.
Name
Meaning
Illustration
E
Enable function input.
FB
Control input.
x
Block's physical output.
x Aux
Block's internal auxiliary output.
Operation
This table describes the different operating phases of the speed detection.
Phase
Description
1
On the rising edge of input E :
  • time-out t1i (masking time) is launched,
  • input x changes to 1.
2
When time-out t1 has elapsed, and then on each edge of input à FB, time-out t2i is launched.
If the rising edges of input FB are spaced out at interval t2i:
  • output x changes to 0,
  • output x Aux changes to 1 (signaling end of movement).
If input E changes to 0, outputs x and x Aux change to 0.
Illustration
The illustration below shows the trend diagram of the speed detection function block.