Omron CJ Series Operation Manual page 277

A , B
2
slave devices are the devices allocated to this Master Unit only, modules are the total number of I/O
modules, selected for the slave devices.

T = (Min. Slave Interval
TR
The total Target Rotation Time is calculated as the sum of all individual Min. Slave Interval values for
each Master Unit on the PROFIBUS network.
From the total Target Rotation Time the Watchdog time for each slave device is calculated as fol-
lows:
T = 3 * T
WD TR
in which: T
TR
Baud rate is the selected baud rate value.
The Watchdog Time value is in turn used to calculate the total Data Control Time:
Data Control Time = 7 * T
Based on measurements, the following values have been determined for the 6 factors in equation
[1]:
Baud rate
[kBits/s]
9.6 414
19.2 418
45.45 1942
93.75 450
187.5 1390
500 2183
1500 4339
3000 11578
6000 23556
12000 47112
A2: 65.1 s, B2: 2 s, C2: 0.5 s
CJ-series PROFIBUS Master Unit Operation Manual for NJ-series CPU Unit (W509)
are constants (in s, determining the cycle time between the Unit and the CPU,
, C
2 2
) [2]
Master
/ Baud rate [3]
is the total Target Rotation Time in
[4]
WD
A1 B1 C1
[t ] [t ] [t
BIT BIT BIT
280 11
280 11
361 11
280 11
310 10
310 10
310 11
410 5
800 10
1600 20
,
t
BIT
Minimum Min. Slave Interval
]
[t ]
BIT
1250
1250
1250
1250
1250
1850
4800
9600
19200
38400
Appendices
[ms]
130
65.1
27.5
13.3
6.67
3.7
3.2
3.2
3.2
3.2
A-11