Mitsubishi Electric FX5 User Manual page 76

Calculation method
The required time "Tinv" for inverter communication instruction in units of "ms" is calculated as follows.
"INT(n)" in the calculation formula indicates an integer obtained by truncating decimal places of "n".
■Length of 1 character
In inverter communication, the communication setting is as shown in the following table.
The length of 1 character is as shown in the following expression.
Length of 1 character
Name
Start bit
Data length
Parity bit
Stop bit
Total
■Time required for inverter communication instructions
The time required for inverter communication instructions is calculated based on the following expression.
Tinv = T + T + T
1 2 3
1
T = INT (
1
Scan time
) } + ΣT
T = { n × (T + T
2 4 5
T = 1 [ms]
3
*1 Time required for one instructions.
T , T and T [n] are calculated as given in the following table.
4 5 6
Communication
time
T
4
T
5
T [n]
6
T [n]+T [n]
7 9
T [n]
8
*2 Refer to Page 75 for the number of sent/received characters.
*3 Refer to Page 75 for the data check time of inverters.
4 INVERTER COMMUNICATION
74
4.4 Specifications
= Start bit + Data length + Parity bit + Stop bit
= 10 [bit]
Setting value

7
Even
1
+ 1 ) × Scan time [ms]
[n] [ms] n: Number of send/receives
6
T [1] + T [2] + T
6 6
Calculation method
1
= ( INT ( + 1 ) × Scan time ) + ( INT (
Scan time
1
= INT ( + 1 ) × Scan time
Scan time
• For Scan time <T [n]+T [n]+T [n]
7 8 9
T [n] + T [n] + T [n]
7 8 9
= ( INT (
Scan time
• For Scan time T
[n]+T [n]+T [n]
7 8 9
T [n] + T [n] + T [n]
7 8 9
= ( INT (
Scan time
1
= { (
Communication speed [bps]
*3
= Data check time in inverters
*1
[3] + •••
6
11
Scan time
) + 1 ) × Scan time + ( INT (
Scan time
) + 2 ) × Scan time + ( INT (
Scan time
) × (No. of characters sent/received
No. of bits
1
7
1
1
10
+ 1 ) × Scan time )
1
+ 1 ) × Scan time )
1
+ 1 ) × Scan time )
*2
× 1-character length) } × 1000