Beckhoff EL922 Series Documentation page 113

Reliable edge detection
Due to the asynchronous operation of the overcurrent protection terminal in relation to the Ether-
CAT master, it is necessary to implement a unique and reliable edge detection for switching on or
resetting the overcurrent protection channels. To reliably detect the edges of the "Switch" or "Reset"
process data outputs within the overcurrent protection terminal, the internal terminal state of these
signals must be sent back to the EtherCAT master as mirrored feedback in the form of process data
inputs. Only by querying and taking these signals into account can it be ensured that all edges are
taken into account. This allows the user to leave a "1" for a signal edge change ("Reset" or
"Switch") until the associated input signal ("State Reset" or "State Switch") reflects or acknowledges
the "1". The same then occurs in the same way as the corresponding "0" signal.
7.5.3.2 Predefined PDO Assignment
The "Predefined PDO Assignment" enables a simplified selection of the process data. The desired function is
selected on the lower part of the "Process Data" tab. As a result, all necessary PDOs are automatically
activated and the unnecessary PDOs are deactivated.
The following predefined PDOs are available:
Name
2 Ch. Standard
Compact 2 Ch.
EL922x
PDO Assignment
SM2, Outputs
SM3, Inputs
SM2, Outputs
SM3, Inputs
Version: 1.0
0x1600 [} 142] (OCP Outputs Channel 1)
0x1601 [} 142] (OCP Outputs Channel 2)
0x1A00 [} 139] (OCP Inputs Channel 1)
0x1A02 [} 146] (OCP Inputs Channel 2)
0x1600 [} 142] (OCP Outputs Channel 1)
0x1601 [} 142] (OCP Outputs Channel 2)
0x1A01 [} 145] (OCP Inputs Channel 1
Compact)
0x1A03 [} 147] (OCP Inputs Channel 2
Compact)
Commissioning
113