Remote I/O Communications Characteristics - Omron SMARTSLICE - 04-2008 Operation Manual

Remote I/O Communications Characteristics

5-1 Remote I/O Communications Characteristics
Note
I/O Response Time
Minimum I/O
Response Time
PLC
DeviceNet
Communications Unit
Slice bus
Input Unit
Output Unit
62
This section describes the characteristics of DeviceNet remote I/O communi-
cations with a Slice I/O Terminal connected to an OMRON Master. Use this
section 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).
(1) The values provided by these equations may not be accurate if another
company's Master or Slave is being used in the network.
(2) This manual describes the communications with the Slice I/O Terminal
only. For details on the Master Unit or overall DeviceNet network, refer to
the DeviceNet Operation Manual (W267). For details on Slaves other
than the Slice I/O Terminal, refer to the DeviceNet DRT2 Series Slaves
Operation Manual (W404).
The I/O response time is the time it takes from the reception of an input signal
at an Input Slave (Input Unit in the Slice I/O Terminal) to the output of the cor-
responding output signal at an Output Slave (Output Unit in the Slice I/O Ter-
minal) after being processed by the PLC's ladder program.
The minimum I/O response time (T
T = T + T + T
MIN IN SL-IN
+ T + T
SL-OUT OUT
T
RT-IN
T
SL-CI
T
SL-IN
T
IN
T : The Input Unit's ON (OFF) delay
IN
T : The Output Unit's ON (OFF) delay
OUT
T : The Slice bus' communications time (input data)
SL-IN
T : The Slice bus' communications time (output data)
SL-OUT
T : The Slice Communications Unit's input data processing time
SL-CI
T : The Slice Communications Unit's output data processing time
SL-CO
) is the total of the following terms:
MIN
+ T + (T - T
SL-CI RT-IN PLC
T
PLC
T
RF
T
RT-OUT
Section 5-1
) + T + T
RF RT-OUT SL-CI
T
SL-CO
T
SL-OUT
T
OUT