Omron GRT1 - 27-11-2006 Operation Manual page 75

Remote Communication Characteristics
Maximum I/O Response
Time
PLC
PROFIBUS
Communications Unit
SmartSlice bus
Input Unit T
Output Unit
Note
PROFIBUS
Communication Cycle
Time (T )
RM
Refresh Time (T )
RF
Master Units for CS, CJ,
C200HX/HG/HE (-Z), and
C200HS PLCs
Note
56
The maximum I/O response time (T
T = T + 2×T
MAX IN
T
RF
T
RM
T
SL-CI
T
SL
IN
T : The Input Unit's ON (OFF) delay
IN
T : The Output Unit's ON (OFF) delay
OUT
T : The SmartSlice bus communication cycle time
SL
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 entire PROFIBUS communication cycle
RM
T : The PLC's cycle time
PLC
T : The PLC's PROFIBUS Unit refresh time
RF
Refer to the GRT1 Series SmartSlice I/O Units Operation Manual for details
on Input Unit's input delay times and Output Unit's output delay times.
The PROFIBUS communication cycle time is the time from the completion of
a Slave's remote I/O communication processing until remote I/O communica-
tion with the same Slave are processed again. The communication cycle time
is used to calculate the maximum I/O response time.
The communication cycle time (T
for the PROFIBUS Master Unit (Refer to the CS/CJ-series PROFIBUS DP
Master Units Operation Manual).
The refresh time is the time required to exchange I/O data between the PLC's
CPU Unit and the PROFIBUS Master Unit. The PLC's cycle time is increased
when a Master Unit is mounted, as shown below.
When a Master Unit is mounted to the PLC, the PLC's cycle time (I/O refresh-
ing) is increased by the amount shown in the following table.
PROFIBUS Master unit
CS1/CJ1W-PRM21
C200HW-PRM21
1. The number of words refreshed is the total number of words in the I/O Area
allocated to the Slaves, including any unused words between the allocated
words. For example, if there are only two Input Slaves with station address-
es 1 and 5, the 5 input words for stations 1 through 5 would be refreshed
even though the input words for stations 2, 3, and 4 are unused.
) is the total of the following terms:
MAX
+ T + T + 2×T
SL SL-CI SL-CO
T
T
T T
PLC
PLC
RF RF
) is defined by the Bus parameter settings
RM
I/O Refresh processing time
0.7 + 0.001 × number of words (ms) (See note 1)
• For C200HX/HG/HE (-Z) PLCs:
1.72 + 0.022 × number of words (ms) (See note 1)
• For C200HS PLCs:
2.27 + 0.077 × number of words (ms) (See note 1)
Section 3-5
+ 2×T + T + T
RM PLC RF OUT
T
PLC
T
RM
T
SL- CO -
T
SL
T
OUT