App - 5 App - 5
MELSEC-Q
APPENDICES
Table 2 Link special relay (SB) list (Continued)
No. Name Description
Availability
Control
station
Normal
station
Remote
master
station
Remote I/O
station
Optical Coaxial Optical Coaxial Optical Coaxial Optical Coaxial
SB0007
(7)
Clear forward loop
transmission errors
Clears the line abnormal detection (SW00CC) of the forward loop
side to 0.
Off: Clear not instructed
On: Clear instructed (valid when on)
SB0008
(8)
Clear reverse loop
transmission errors
Clears the line abnormal detection (SW00CD) of the reverse loop
side to 0.
Off: Clear not instructed
On: Clear instructed (valid when on)
6
SB0009
(9)
Clear loop switch count
Clears the loop switch count (SW00CE to SW00E7) to 0.
Off: Clear not instructed
On: Clear instructed (valid when on)
SB000A
(10)
Clear transient
transmission errors
Clears the transient transmission errors (SW00EE, SW00EF) to
0.
Off: Clear not instructed
On: Clear instructed (valid when on)
SB000B
(11)
Transient transmission
error area setting
Designates whether to overwrite or retain the transient
transmission errors (SW00F0 to SW00FF).
Off: Overwrite
On: Retain
3
4
SB000F
(15)
Clear minor errors
Clears all of minor errors detected by remote I/O stations.
This error clear is executed on all remote I/O stations.
While SB000F is ON, no minor error is detected on all remote I/O
stations.
In a multiplexed remote I/O network (including the one that
supports redundant systems), this can be manipulated only from
the station acting as a master.
Off: Clear not instructed
On: Clear instructed (valid when on)
SB0011
(17)
Data link operation
designation
Designates the data link operation.
Off: No switch instruction
On: Switch instruction (valid when on)
When On is detected, data link switches from Online (normal
data link) operation to Online (debug) operation, or from Online
(debug) operation to Online (normal operation).
Debug operation
Online operation
SB0011
Debug operation
SB0014
(20)
Remote sub-master
station switching
command
Forcibly directs the remote sub-master station that is performing
master operation to shift to sub-master operation. (It is invalid for
the redundant system.)
Off: Without directive
On: With directive
SB0018
(24)
System switching
monitoring time setting
valid flag
Indicates whether the system switching monitoring time setting
(SW0018) is valid or invalid in case of a data link error.
Off: Invalid
On: Valid (valid at the time of startup)
SB0020
(32)
Module status
Indicates the communication status between the network module
and the CPU module.
Off: Normal
On: Abnormal
SB0040
(64)
Network type
(host)
Indicates the network type set with the parameters of the host's
network module.
Off: PLC to PLC network
On: Remote I/O network
SB0041
(65)
Host station's redundant
function support
information
Indicates the station supports the redundant function or not.
Off: Redundant function not supported
On: Redundant function supported
SB0042
(66)
Power supply status of
host
Indicates the external power supply status to the host's
QJ71LP21S-25. (When using QJ71LP21-25, 0 is ON.)
Off: Not supplied (EXT.PW LED is OFF.)
On: Supplied (EXT.PW LED is ON.)
SB0043
(67)
Online switch
(host)
Indicates the mode set by the switch of the host's network
module.
Off: Online (mode setting is 0 or 4); "Parameter setting mode
becomes valid"
On: Other than online (mode setting is other than 0)
3: Valid only when SB0047 is off. When it turns on (error), the last data are retained.
4: Minor errors are the type of errors that do not affect the CPU operation. (Refer to Section 8.3.3)
6: The SB0009 should be kept on until the SW00CE becomes "0."