Panasonic FP7 Series User Manual

6.4 Response Time of PLC Link
6.4.1 Response Time of One Transmission Cycle
The maximum value of one transmission cycle time (T) can be calculated using the following
formula.
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Calculation formula
(1) Ts (transmission time per unit)
Calculation
formula
Ts = Scan time + Tpc (PLC link sending time)
Tpc = Ttx (sending time per byte) x Pcm (PLC link sending byte size)
Ttx = 1/ (baud rate kbps × 1000) × 11 ms … approx. 0.096 ms when 115.2 kbps
Pcm = 23 + (number of relay words + number of register words) x 4 (an ASCII code needs
multiplication by four)
(2) Tlt (link table sending time)
Calculation
formula
Tlt = Ttx (sending time per byte) x Ltm (link table sending size)
Ttx = 1/ (baud rate kbps × 1000) × 11 ms … approx. 0.096ms when 115.2 kbps
Ltm = 13 + 2×n (n = No. of added units)
(3) Tso (master unit scan time)
To be checked using tool software.
(4) Tlk (link addition processing time)
Calculation
formula
If all units have been added, Tlk = 0
Tlk = Tlc (link addition command sending time) + Twt (addition waiting time)
+ Tls (sending time for command to stop transmission if link error occurs) + Tso (master unit
scan time)
Tlc = 10 × Ttx (sending time per byte)
Ttx = 1/ (baud rate kbps × 1000) × 11 ms … approx. 0.096 ms when 115.2 kbps
Twt = initial value 400 ms
Tls = 7 × Ttx (sending time per byte)
Ttx = 1/ (baud rate kbps × 1000) × 11 ms … approx. 0.096ms when 115.2 kbps
Tso = master unit scan time
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Calculation example
Condition Calculation process
One transmission cycle
time (T)
1
16-unit link with all units added
Max. unit number = 16
Ttx=0.096
Each Pcm=23+(4+8)×4=71 bytes
T max.=Ts+Tlt+Tso
7.82×16+4.32+1
6.4 Response Time of PLC Link
WUME-FP7COM-07 6-13

Panasonic FP7 Series Specifications

General

Brand	Panasonic
Model	FP7 Series
Category	Controller
Language	English