Omron CP1H-CPU - 05-2006, Operation Manual

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95
Computing the Cycle Time
Section 2-7
CJ-series Special I/O Unit I/O Refresh Times (Examples)
Increase in Cycle Time Caused by CPU Bus Units
Note The refresh time for I/O built into the CPU Unit is included in the overseeing
time.
When pulse output ports 2 and 3 are used, the cycle time increases in propor-
tion to the output frequency.
Cycle time rate of increase (%) from pulse output ports 2 and 3 = Output fre-
quency (kHz)
×
0.1.
Examples:
30 kHz: Approx. 3%
100 kHz: Approx. 10%
2-7-5 Cycle Time Calculation Example
The following example shows the method used to calculate the cycle time
when CPM1A Expansion I/O Units only are connected to a CP1H CPU Unit.
Name Model I/O refresh time per Unit
CompoBus/S Mas-
ter Unit CJ1W-SRM21 Allocated one unit number 0.15 ms
Allocates two unit numbers 0.17 ms
Analog Input Unit CJ1W-AD041/081(-V1) 0.16 ms
Analog Output Unit CJ1W-DA021/041/08V 0.16 ms
Analog I/O Unit CJ1W-MAD42 0.167 ms
Temperature Con-
troller Unit CJ1W-TC @@@ 0.367 ms
Name Model Time Remarks
Controller Link
Unit CJ1W-CLK21-V1 0.15 ms There will be an increase of 1.0 ms + 0.7
µ
s
×
number of
data link words.
There will be an additional increase of the event execution
times when message services are used.
Serial Commu-
nications Unit CJ1W-SCU41
CJ1W-SCU21 0.24 ms There will be an increase of up to the following time when a
protocol macro is executed:
0.7
µ
s
×
maximum number of data words sent or received (0
to 500 words)
There will be an increase of the event execution times when
Host Links or 1:N NT Links are used.
Ethernet Unit CJ1W-ETN11/21 0.17 ms If socket services are executed with software switches,
there will be an increase of 1.4
µ
s
×
the number of bytes
sent/received.
There will be an increase of the event execution times when
FINS communications services, socket services for CMND
instructions, or FTP services are performed.
DeviceNet Unit CJ1W-DRM21 0.5 ms + 0.7
µ
s
×
Num-
ber of allocated words
The number of allocated words includes all I/O areas allo-
cated to all slaves, even unused words within the I/O areas.
If message communications are performed, the number of
words for message communications must be added to the
number of allocated words at the left, but only during the
cycles when the message communications are performed.