BECKHOFF EL6900-FB - Manual (Page 63)

Function blocks
Function blocks for TwinSAFE logic terminals 61
3.9 The EDM function block
3.9.1 Functional description
The FB EDM (External Device Monitor) is used for time monitoring of signals Mon1 and Mon2. Switch-on
and switch-off monitoring can be configured. Both monitoring functions are inactive by default.
Switch-on monitoring checks whether signal Mon2 is set to 0 within the set time (maximum 10000 ms)
following a switch from 0 to 1 of signal Mon1.
Switch-off monitoring checks whether signal Mon2 is set to 1 within the set time (maximum 10000 ms)
following a switch from 1 to 0 of signal Mon1.
If the set monitoring time is exceeded the error output for the block is set. It can be reset via the ErrAck
signal for the TwinSAFE group.
Figure 3-25: EDM function blocks
Note
KL6904
The EDM block is not available in the KL6904.