Omron DRT1 Series - Page 322

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Remote I/O Communications Characteristics Section 7-1
T
RM
= Σ (Communications time for each Slave)
+ MULTIPLE I/O TERMINAL processing time
+ Explicit messages processing time
+ 0.01
× N + 1.0 [ms]
Communications time for each Slave: Time required for each Slave
Σ (Communications time for each Slave) is the total of the processing time
of each Slave in the network.
MULTIPLE I/O TERMINAL processing time:
3.5 [ms]
Only when Slaves with input, output, or mixed I/O of more than 8
bytes exist.
Explicit messages processing time:
0.11
× T
B
+ 0.6 [ms]
Explicit message communications execution time
T
B
: Baud rate factor
(500 kbps: T
B
= 2; 250 kbps: T
B
= 4; 125 kbps: T
B
= 8)
N: Number of Slaves
Communications Time for
each Slave
The following equations show the communications time per Slave (T
RT
) for
each kind of Slave Unit.
Output Slaves with 8 Bytes of Output Max.
T
RT
= 0.016 ×T
B
× S
OUT1
+ 0.11 × T
B
+ 0.07 [ms]
S
OUT1
: The number of Output Slave output words
T
B
: The baud rate
(500 kbps: T
B
= 2; 250 kbps: T
B
= 4; 125 kbps: T
B
= 8)
Input Slaves with 8 Bytes of Input Max.
T
RT
= 0.016 ×T
B
× S
IN1
+ 0.06 × T
B
+ 0.05 [ms]
S
IN1
: The number of Input Slave input words
T
B
: The baud rate
(500 kbps: T
B
= 2; 250 kbps: T
B
= 4; 125 kbps: T
B
= 8)
Mixed I/O Slaves with 8 Bytes of I/O Max.
T
RT
= 0.016 × T
B
× (S
OUT2
+ S
IN2
) + 0.11 × T
B
+ 0.07 [ms]
S
OUT2
: The number of Mixed I/O Slave output words
S
IN2
: The number of Mixed I/O Slave input words
T
B
: The baud rate
(500 kbps: T
B
= 2; 250 kbps: T
B
= 4; 125 kbps: T
B
= 8)
Input Slaves, Output Slaves, or Mixed I/O Slaves with Over 8 Bytes of I/O
T
RT
= T
OH
+ T
BYTE-IN
× B
IN
+ T
BYTE-OUT
× B
OUT
[ms]
T
OH
: The protocol overhead
T
BYTE-IN
: The input byte transmission time
B
IN
: The number of input bytes
T
BYTE-OUT
: The output byte transmission time
B
OUT
: The number of output bytes
Baud rate T
OH
T
BYTE-IN
T
BYTE-OUT
500 kbps 0.306 ms 0.040 ms 0.036 ms