Mitsubishi Electric Melsec QJ71LP21 Reference Manual page 454

APPENDICES
No. Name
3
External power supply
SB008C
information
(140)
3
Module type of each
SB008D
station
(141)
SB0090
Host loop status
(144)
3
SB0091 Forward loop status
(145)
3
Forward loop status of
SB0092
remote master station
(146)
3
SB0095 Reverse loop status
(149)
3
Reverse loop status of
SB0096
remote master station
(150)
3
SB0099 Forward loop loopback
(153)
3
SB009A Reverse loop loopback
(154)
3: Valid only when the SB0047 is off. When it turns on (error), the last data are retained.
7: Available only in the remote sub-master station.
App - 15
Table 3 Link special relay (SB) list (continued)
Description
Indicates the information of the external power supply (including
the host).
Off: All stations are without external power supply
On: Stations with external power supply exist
When any station with external power supply exists, the status of
each station can be checked in Power supply status of each
station (SW008C to SW008F).
Depending on the timing of the link refresh, Power supply status
of each station (SW008C to SW008F) and the update may be
offset by one sequence scan.
Indicates the module type of each station.
Off: All stations are NET/10 type modules
On: NET/10H type modules exist
Indicates the host's loop status.
Off: Normal
On: Abnormal
When an error is identified, the error details can be checked by
Loopback information (SW0090).
Indicates the status of stations connected to the forward loop.
Off: All stations normal
On: Faulty station exists
When any faulty station exists, the status of each station can be
checked in Forward loop status of each station (SW0091 to
SW0094).
Depending on the timing of the link refresh, Forward loop status
of each station (SW0091 to SW0094) and the update may be
offset by one sequence scan.
Indicates the forward loop status of the remote master station.
Off: Normal
On: Error
Indicates the status of stations connected to the reverse loop.
Off: All stations normal
On: Faulty station exists
When any faulty station exists, the status of each station can be
checked in Reverse loop status of each station (SW0095 to
SW0098).
Depending on the timing of the link refresh, Reverse loop status
of each station (SW0095 to SW0098) and the update may be
offset by one sequence scan.
Indicates the reverse loop status of the remote master station.
Off: Normal
On: Error
Indicates the loopback status of the forward loop while the
system is operating.
Off: Not executed
On: Executing stations exist
(Executing stations are stored in the SW0099)
Indicates the loopback status of the reverse loop while the
system is operating.
Off: Not executed
On: Executing stations exist
(Executing stations are stored in the SW009A)
Use permitted/prohibited
Control Normal
station station
Loop Bus Loop Bus
[Availability column] Loop: optical loop, Bus: coaxial/twisted bus
MELSEC-Q
Remote
Remote I/O
master
station
station
Loop Bus Loop Bus
7
: Available, : Not available
App - 15