Mitsubishi Electric Melsec-k Instruction Manual page 28

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3. HARDWARE CONFIGURATION AND HANDLING
Slave Channel to Be Re-set
3.10 Concept of Channel Numbers in Optical Link
Loop
As shown in Fig, 3.8, when
RESET Switch
Master channel
Automatic
Reconnection Mode
the same channel
numbers exist inside a link loop (in this example,
there are two Number
2
channels), send data from
the master channel are sent to each channel, each
channel receives only the data which is required a t i t s
own channel, and processing
is
continued.
ONLINE- Re-setting of
OFFLINE switch channel number
"Number 2 channel"
"Number
2
channel"
0
Fig.
3.8
Master channel
"Number
2
channel-A"
"Number 2 channel-F"
Fig. 3.9
The example of data sending from the slave channel
t o the master channel is shown in Fig, 3.9. In this
instance, data are sent from Number
2
channel t o the
master channel. In this case, however, since there are
two Number
2
channels, the send data of the first
Number
2
channel (Number
2
channel-F) are merely
sent t o the adjacent Number
2
channel (Number
2
channel-A) and are not transferred to the master
channel (because the switch across R and D of
Number
2
channel-A is open). Therefore, when the
same channel numbers exist within a link loop, the
master channel receives data from the last channel
in relation to the master channel (in this example,
only the data of Number
2
channel-A are trans-
ferred to the master channel). Accordingly, since
normal link data transfer cannot be performed,
avoid setting the same channel numbers in the loop.
All channel sutomatic
reconnection mode
Master channel i s in
automatic reconnection
i o d e . Slave channels to be
re-set are not in automatic
reconnection mode.
Master channel i s not in
automatic reconnection
mode. Slave channels are
in automatic reconnection
mode.
All channels are not in
automatic recon nectio n
mode.
*I
Re-setting of
channel number
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I I
ONLINE- R e-se
t
OFFLINE switch
1
c ! $ t % l
1
slave channel
Not required
Online
0 0
"I: To reset the system in the all channel automatic reconnection mode, be sure to reset the slave channels and
Table 3.2 Channel Number Re-setting Method and Syatem Resetting Method after Re-setting
then the master channel.
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