5.2.7
Link special relay (SB)
The Link special relay (SB) is a relay that indicates various communication status and detected errors. Each of this
device area is turned on or off according to a factor occurred during data link. Status of the data link can be confirmed
by monitoring the link special relay.
MELSEC-L CC-Link System Master/Local Module User's Manual
5.2.8
Edge relay (V)
The edge relay (V) is a device in which the on/off information from the beginning of the ladder block. Contacts only can
be used. (Coils cannot be used.) The edge relay of the same number cannot be set.
Detecting a leading edge and execute it in the program configured using index modification
Ex.
Ex.
[Program example]
*1
The on/off information for X0Z1 is stored in the V0Z1 edge relay. For example, the on/off information of X0 is stored in
V0, and that of X1 is stored in V1.
[Timing chart]
When Z1 = 0
When Z1 = 1
236
*1
*1
ON
X0
OFF
ON
V0
OFF
ON
M0
OFF
1 scan
X1
OFF
V1
OFF
M1
OFF
Stores on/off information of X0, X1, and X10.
Clears index register (Z1).
Specifies the number of repeats
(10 times).
Turns on M0Z1 for 1 scan, followed
by rise of X0Z1.
Increments (+1) index register (Z1).
Returns to FOR instruction.
Turns on for 1 scan by rise of X0.
ON
ON
Turns on for 1 scan by rise of X1.
ON
1 scan