Omron CJ1W-PNT21 Operation Manual page 64

CJ1W-PNT21 PROFINET IO Controller DTM
4-3-3-4 IO Device Area
Allocation Areas
Module List Box
50
Item
Data Hold Factor
Watchdog Time (ms)
Data Hold Time (ms)
The IO Device Area displays the mapping of the I/O data of the allocated IO
Devices onto the PLC memory areas. The mapping can be made
automatically or be changed by the user prior to downloading.
The figure below shows the IO Device Area, more in particular the Output
Allocation tab.
The IO Device Area allocation tabs define how the I/O data of each of the
slave devices is mapped onto the PLC memory. The Slave area tab contains
two tabs, one for Output Allocation and one for Input Allocation. Each tab
contains an overall module list showing all the output or input data per slave,
along with the Module names, sizes, data types and start addresses. This data
is transferred to the Master DTM by each of the allocated slave DTMs. If no IO
Devices have been allocated or configured the list will be empty.
The Module List Box list contains the following information (the table applies to
the lists in the Input and Output Allocation tabs, see also the above figure).
Description
The Data Hold Factor is a multiplication factor on the Update
Rate to define the datahold timeout. The Data Hold Time is
the time that an IO Device will keep its Outputs set to the last
known state after a successful data exchange. If the Data
Hold Time elapses, the Outputs of the IO Device will turn to a
safe state as defined by the configuration of each device. The
Data Hold Factor must be equal to or larger than the
Watchdog Factor
The Watchdog Time is the multiplication of the Update Rate
and the Watchdog Factor.
The Data Hold Time is the multiplication of the Update Rate
and the Data Hold Factor.
Figure 4.11: IO Device area
Section 4-3