Mitsubishi MELSEC AJ65BT-R2 User Manual page 41

3 SPECIFICATIONS
(2) Calculation example
(a) Transmission time
An example of calculating the transmission time for transmitting 10 words
(20 bytes) of data is shown below.
Transmission size of each area
Transmission speed
No. of connected modules
Master station sequence program scan time
Transmission speed
Data bit length
Stop bit length
Parity bit
1) When the master station is the A/QnA series
LS = 51.2 {29.4 + (8 × 4.8) + (8 × 9.6) + (1 × 32.4) + (1 × 4.8) + (1 × 9.6)}
+ 1300 = 11100 µ s (11.1ms)
Data transmission time = 20 × 10/9600 = 0.0208s (20.8ms)
Transmission time = 20 × 2 + 11.1 × 6 + (11.1 × 2) *
2) When the master station is the Q series
LS = 51.2 {27 + (8 × 4.8) + (8 × 9.6) + (1 × 30) + (1 × 4.8) + (1 × 9.6)}
+ 1300 +0 +0 = 10854 µ s (10.9ms)
Data transmission time = 20 × 10/9600 = 0.0208s (20.8ms)
Transmission time = 20 × 2 + 10.9 × 4 + (10.9 × 2) *
1
*
2
*
3
*
4
*
5
*
Item
+ {(136 + 16)/72 × 11.1} *
+ {(32 + 16)/16 × 11.1} *
= 149.6 + 3 × 11.1 + 8 × 11.1 + 3 × 11.1
= 305ms
+ {(136 + 16)/72 × 10.9} *
+ {(32 + 16)/16 × 10.9} *
= 126.2 + 3 × 10.9 + 8 × 10.9 + 3 × 10.9
= 278.8ms
R2 (R2 internal processing time)
Data transmission time
Transmission area 1 request/response scan (88
worth)
Transmission area 2 request/response scan (200
worth)
Status storage area request/response scan (20
worth)
3 - 21
MELSEC-A
Setting details
Default value
156kbps
Only one R2 module
20ms (Hypothetical)
9600bps
8
1
Even
1 2
+ 20.8 *
3 + {(512 + 16)/72 × 11.1} *
5
1 2
+ 20.8 *
3 + {(512 + 16)/72 × 10.9} *
5
(136 words)
H
(512 words)
H
(32 words)
H
4
4