Mitsubishi Electric Melsec QJ71LP21 Reference Manual page 98

3 SPECIFICATIONS
Total number of stations
Communication speed
Communication speed
3 - 44
(f) Link scan time in the twisted bus system
The link scan time in the twisted bus system is obtained by the equation
below using the following variables:
• Network type
• Number of assignment points of the link device
• Constant 1 to 3
1) MELSECNET/H mode
[Link scan time]
LS = KB1+(KB2 total number of stations) +
2) MELSECNET/H Extended mode
[Link scan time]
LS = KB1+(KB2 SP) +
LS : Link scan time
KB1 to 3: Constant
1 to 8
KB1 8.0
156kbps 312kbps 625kbps 1.25Mbps 2.5Mbps
KB2 4.6
156kbps 312kbps 625kbps 1.25Mbps 2.5Mbps
KB3 0.064
LB : Total points of link relays (LB) used in all
stations
LW : Total points of link registers (LW) used in all
stations
LX : Total points of link inputs (LX) used in all
stations
LY : Total points of link outputs (LY) used in all
stations
T : Maximum number of bytes sent by the transient transmission in one
link scan.
F : Number of stations returned to the network (Only if there are faulty
stations. : Maximum number of stations returned to the network in 1
scan (set value))
SP : Refer to Section 3.3.3 (e).
1: Total link device points set up in the network range parameter
assignment.
Note that the points assigned to reserved stations are excluded.
2: "0" when not used.
LB+LX+(LW
+ (T KB3) + (F 4) [ms]
LB+LX+(LW 16)
KB3 + (T KB3) + (F 4) [ms]
8
9 to 16 17 to 24 25 to 32
8.5 8.9 9.3
3.83 3.06 2.55
0.032 0.016 0.008
1
1
1
1
2
MELSEC-Q
16)
KB3
8
5Mbps 10Mbps
2.05 1.55 1.05
5Mbps 10Mbps
0.004 0.002 0.001
Refer to Section
3.3.3.
3 - 44