13 Communications Performance and Communications Load
13-24
NY-series Industrial Panel PC / Industrial Box PC Built-in EtherNet/IP Port User’s Manual (W563)
The tag data is transferred during task processing. Therefore, the tag data transfer process is added to
the task processing for tasks set as a tag’s refreshing task. This requires you to make adjustments to
the variable access time and task period in the Task Setup so that these processes are completed
within a single task period.
1
Calculate the time required for the data transfer and set the result as the "variable access
time"
*
.
For the formula for calculating the time required for the data transfer, refer to
* If the same refreshing task is set for multiple tag sets, calculate the total time required for all tags in tag
sets.
2
Set the variable access time in the Task Setup to a value equal to or greater than the value cal-
culated in step 1 above.
Adjust the task period time after adding in the time calculated in step 1. Use the Sysmac Studio
to set the variable access time and task period settings. For details, refer to the
NY-series Indus-
trial Panel PC / Industrial Box PC Software User’s Manual
(Cat. No. W558).
Tag data is transferred based on the actual time required for the transfer (task period
×
number of data
transfers), regardless of the packet interval (RPI) setting. Therefore, set the packet interval (RPI)
according to the following guideline.
Actual time required for data transfer (Task period
×
Number of data transfers) < RPI
For details on the actual time required to transfer data, refer to
13-3-2 Built-in EtherNet/IP Port Data
.
Example: Relationship between the RPI Setting and the Time Required for Data Transfer
•
Task period: 10 ms
•
Number of data transfers: 2
•
Actual time required for data transfer: 10 ms
×
2 times = 20 ms
Regardless of the RPI value, the time required for the data transfer is 20 ms.
13-3-3 Relationship between Task Periods and Packet Intervals (RPIs)
Effect of Tag Data Links on Task Periods
Adjusting Packet Intervals (RPIs) According to the Task Periods
T
as
k period: 10 m
s
Ex
a
mple: Prim
a
ry periodic t
as
k
To Controller #2
To Controller #2
Refre
s
hing period
d
u
ring RPI
10 m
s
I/O refre
s
hing
U
s
er progr
a
m exec
u
tion
Motion control
S
end d
a
t
a
proce
ss
ing
S
end d
a
t
a
proce
ss
ing
T
as
k period × 2
Time re
qu
ired to tr
a
n
s
fer d
a
t
a
from Controller #1: 20 m
s
T
as
k period: 10 m
s
Ex
a
mple: Prim
a
ry periodic t
as
k
RPI of 10 m
s
RPI of 20 m
s
T
as
k period × 2
(1)
(2)
(1) (2)
Refre
s
hing period
d
u
ring RPI:
20 m
s
Tr
a
n
s
mi
ss
ion
p
a
th
Tr
a
n
s
mi
ss
ion
p
a
th
Controller#1
Controller#1
D
a
t
a
link proce
ss
ing
(
s
y
s
tem common proce
ss
ing
3
)
OI MC
UPG
OI
UPG
MC
T
a
g d
a
t
a
link
s
ervice
T
a
g d
a
t
a
link
s
ervice
OI MC
UPG
OI MC
UPG
OI MC
UPG
OI MC
UPG
OI MC
UPG
OI MC
UPG
OI MC
UPG
Summary of Contents for Sysmac NY512-1300
Page 459: ......
