Table of Contents
Advertisement
Remote I/O Communications Characteristics
7-1
Remote I/O Communications Characteristics
7-1-1
I/O Response Time
CVM1- and CV-series PLCs (Asynchronous Mode)
Minimum I/O Response
Time
110
This section describes the characteristics of DeviceNet remote I/O communi-
cations when OMRON Master and Slave Units are being used. Use this sec-
tion for reference when planning operations that require precise I/O timing.
The equations provided here are valid under the following conditions:
• The Master Unit is operating with the scan list enabled.
• All of the required slaves are participating in communications.
• No errors are being indicated at the Master Unit.
• Messages are not being produced in the Network (from another com-
pany's configurator, for example).
Note The values provided by these equations may not be accurate if another com-
pany's master or slave is being used in the Network.
The I/O response time is the time it takes from the reception of an input signal
at an Input Slave to the output of the corresponding output signal at an Output
Slave after being processed by the ladder program at the master.
The minimum I/O response time occurs when the DeviceNet Master Unit
refreshing is executed just after the input signal is received by the master and
instruction execution is completed within one peripheral servicing cycle.
PLC cycle (instruction
execution cycle)
PLC cycle (peripheral
servicing cycle)
Master Unit processing
Input
Output
T
IN
T
:
The Input Slave's ON (OFF) delay (Minimum value: 0)
IN
T
:
The Output Slave's ON (OFF) delay (Minimum value: 0)
OUT
T
:
The Input Slave's communications time/slave
RT-IN
T
:
The Output Slave's communications time/slave
RT-OUT
T
:
The PLC's peripheral servicing cycle time
PLC2
Instruction execution
cycle time
Instruction
execution
Peripheral
servicing cycle
time
T
T
T
RT-IN
PLC2
RT-OUT
Section 7-1
T
OUT
Advertisement
Chapters
Table of Contents
