Omron K3HB, Техническое руководство пользователя

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8-2
Remote I/O Communications Performance
Section 6-1
Com
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uni
cat
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P
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rf
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6-1 Remote I/O Communications Performance
The performance of remote I/O communications between an OMRON Master
Unit and OMRON Slave is described in this section. Use this information for
reference with precise timing is required.
The following conditions are assumed in the calculations provided in this sec-
tion.
• The Master Unit is operating with the scan list enabled.
• All required slaves are participating in communications.
• No error has occurred in the Master Unit.
• No messages are being sent on the network by Configurators or other
devices from other manufacturers.
Note The calculations given in the section may not be accurate if a master from
another manufacturer is used or if slaves from other manufacturers are used
on the same network.
6-1-1 I/O Response Time
The I/O response time is the time required from when the master is notified of
an input on an input slave until an output is made on an output slave (includ-
ing ladder diagram processing in the PLC).
CS/CJ-series,
C200HX/HG/HE (-Z), and
C200HS PLCs Minimum I/O Response Time
The minimum I/O response time occurs when the slave I/O refresh is per-
formed immediately after the input is received by the master and the output is
sent to the output slave at the beginning of the next I/O refresh.
T
IN
: ON/OFF delay time of the input slave (0 used as minimum value)
T
OUT
: ON/OFF delay time of the output slave (0 used as minimum value)
T
RT-IN
: Communications time for one slave for input slaves
T
RT-OUT
: Communications time for one slave for output slaves
T
PC
: Cycle time of PLC
T
RF
: DeviceNet Unit refresh time at PLC
Note Refer to the operation manuals for the slaves for the input slave ON/OFF
delay times and the output slave ON/OFF delay times. Refer to
6-1-2 Com-
munications Cycle time and Refresh Processing Time and to the operation
manual for the PLC for the PLC cycle time.
The minimum I/O refresh time can be calculated as follows:
T
MIN
= T
IN
+ T
RT-IN
+ (T
PC
−
T
RF
) + T
RT-OUT
+ T
OUT
TPC
T
RF
PLC
Master Unit
Input
Output
T
IN
T
RT-OUT
(T
PC-
T
RF
)
T
OUT
T
RT-IN
Program execution