I/O Communication Characteristics - Omron GRT1-PNT Operation Manual

I/O communication characteristics

3-6

I/O communication characteristics

I/O Response Time
Minimum I/O Response
Time
This section describes the characteristics of PROFINET IO communication
between a GRT1-PNT and an OMRON IO Controller Unit. Use this section for
reference when planning operations that require precise I/O timing.
The equations provided here are valid under the following conditions:
• All of the required IO Devices are participating in communication.
• No errors are being indicated by the IO Controller Unit.
• No third-party IO Controller or communication is active in the network.
Note This manual describes the communication with the SmartSlice I/O System only. For
detail on the IO Controller Unit or overall PROFINET IO network, refer to the CJ-series
PROFINET IO Controller Units Operation Manual.
The I/O response time is the time between the reception of an input signal at
an Input Unit in the SmartSlice I/O System and the actual output signal
occurring on an Output Unit in the SmartSlice I/O System after processing by
the PLC program.
The minimum I/O response time (T
T =T + T
MIN IN SL-IN
+ T
SL-OUT
where:
T :The Input Unit's ON (OFF) delay
IN
T :The minimum I/O response time
MIN
T :The Output Unit's ON (OFF) delay
OUT
T :The PLC's cycle time
PLC
T :The PLC's PROFINET IO Unit refresh time
RF
T :The PROFINET IO communication time
RT
T :The Input Device's communication time
RT-IN
T :The Output Device's communication time
RT-OUT
T :The SmartSlice bus' communication time (input data)
SL-IN
T :The SmartSlice Communication Unit's input data processing time
SL-CI
T :The SmartSlice Communication Unit's output data processing time
SL-CO
T :The SmartSlice bus' communication time (output data)
SL-OUT
PLC
PROFINET
Communications Unit
SmartSlice bus
Input Unit
Output Unit
MIN
+ T + T + (T
SL-CI RT-IN
+ T
OUT
T
RF
T
RT-IN -
T
SL-CI -
T
SL-IN -
T
IN
) is the total of the following terms:
− T
) + T
PLC RF RT-OUT
T
PLC
T
RT-OUT -
T
SL- CO -
Section 3-6
+ T
SL-CO
T
SL- OUT -
T
OUT
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