Panasonic FPS Series, User Manual

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Communication
FP Σ User's Manual
240
Tlc = 10 × Ttx
Ttx = 1/transmission speed
×
1000
×
11ms
≈
0.096ms at 115200bit/s
Twt = Initial value 400ms (can be changed using SYS1 instruction)
Tls = 7 × Ttx
Ttx = 1/transmission speed × 1000 × 11ms ≈ 0.096ms at 115200bit/s
Tlc (link addition command sending time)
Twt (addition waiting time)
Ttx (sending time per byte)
Tls (link error stop command sending time)
Tso (master station scan time)
Ttx (sending time per byte)
Tso (master station scan time)
Calculation example 1
Conditions: All stations have been added to a 16-unit link. Highest station number = 16.
Relays and registers have been evenly allocated. Scan time for each PLC: 1ms.
Ttx = 0.096
Pcm (per station) = 23 + (4 + 8)
×
4 = 71
Tpc = Ttx × Pcm = 0.096 × 71 ≈ 6.82ms
Ts (per station) = 1 + 6.82 = 7.82ms
Tlt = 0.096
×
(13 + 2
×
16) = 4.32ms
Given the above conditions, the maximum value for the transmission time (T) of one cycle will be:
T max. = 7.82
×
16 + 4.32 + 1 = 130.44ms
Calculation example 2
Conditions: All stations have been added to a 16-unit link. Highest station number = 16.
Relays and registers have been evenly allocated. Relays and registers have been evenly
allocated. Scan time for each PLC: 5ms.
Ttx = 0.096
Pcm (per station) = 23 + (4 + 8) × 4 = 71
Tpc = Ttx
×
Pcm = 0.096
×
71
≈
6.82ms
Ts (per station) = 5 + 6.82 = 11.82ms
Tlt = 0.096 × (13 + 2 × 16) = 4.32ms
Given the above conditions, the maximum value for the transmission time (T) of one cycle will be:
T max. = 11.82 × 16 + 4.32 + 5 = 198.44ms
Calculation example 3
Conditions: All but one station have been added to a 16-unit link. Highest station number = 16.
Relays and registers have been evenly allocated. Scan time for each PLC: 5ms.
Ttx = 0.096
Ts (per station) = 5 + 6.82 = 11.82ms
Tlt = 0.096 × (13 + 2 × 15) = 4.31ms
Tlk = 0.96 + 400 + 0.67 + 5 ≈ 407ms
Note: The default value for the addition waiting time is 400ms.
Given the above conditions, the maximum value for the transmission time (T) of one cycle will be:
T max. = 11.82
×
15 + 4.13 + 5 + 407 = 593.43ms