Mitsubishi Electric SW0DNC-MNETH-B User Manual page 28

1 OVERVIEW
Control station
(Station No.1)
Q80BD
Personal
-J71
computer
LP21
-25
Q80BD
Personal
-J71
computer
LP21
-25
Normal station
(Station No.6)
1 - 4
(9) External power supply allows continuous network communication
even during power-off of personal computer. (Function of the
Q80BD-J71LP21S-25)
Since power is supplied externally, the Q80BD-J71LP21S-25 can continue
network communication (baton passing) even if a personal computer is powered
off and data link cannot be performed.
Therefore, a normally operating station connected between other stations with
power-off computers will not be disconnected from the data link.
Another advantage is that the link scan time is stabilized since loopback can be
also prevented.
Q
CPU
Normal station
(Station No.5)
When station No. 3 and No.5 use MELSECNET/H boards without the external
power supply function and if their personal computers are powered off, station
No.4 is cut off from the network as well as No.3 and No.5.
Station No.1
Station No.6
Normal station
(Station No.2)
QJ71
LP21
-25
Q80BD
Personal
-J71
computer
LP21S
-25
External power
supply
Station No.2
Station No.5
Personal computer
Normal station
(Station No.3)
Q80BD
Personal
-J71
computer
LP21S
External power
-25
Data link continued
Q QJ71
CPU LP21
-25
Normal station
(Station No.4)
Personal computer
Station No.3
Station No.4 Disconnected
MELSEC
supply
1 - 4