Appendix 4 Special Relay (Sm) For Remote I/O Stations - Mitsubishi Electric MELSEC Q Series Reference Manual

APPENDICES

Appendix 4 Special Relay (SM) for Remote I/O Stations

Number
Name
Meaning
Explanation
Set by (When set)
Corresponding ACPU
M9
Applicable CPU
For details on the following items, refer to the following.
• CPU
• Networks
• SFC
App - 33
The special relay (SM) is an internal relay whose specification is fixed in the
programmable controller. For this reason, the special relay cannot be used in the same
way as other internal relays used in sequence programs. However, the bit of the
special relay can be turned ON or OFF as needed to control the CPU module or the
remote I/O module.
To monitor and turn ON or OFF the bit of the special relay of the remote I/O module,
use GX Developer. Connect GX Developer to the remote master station or the remote
I/O station to perform monitoring and device tests.
The list in this section provides only the special relay areas related to the remote I/O
module. The following table shows how to read the special relay list.
Item
• Indicates the number of the special relay.
• Indicates the name of the special relay.
• Indicates the nature of the special relay.
• Contains detailed information about the nature of the special relay.
• Indicates whether the relay is set by the system or user, and, if it is set by the system, when
setting is performed.
<Set by>
S
U
S/U : Set by both system and user
<When set>
Each END
Initial
Status change
Error
Instruction execution : Set when instruction is executed
Request
System switch
• Indicates special relay M9
(Indicates M9
model QCPU and Redundant CPU are not supported.)
• Items indicated as "New" have been newly added for Q/QnACPU
• Indicates the applicable CPU module.
: Can be applied to all types of QCPU and QnACPU
QCPU: Can be applied to all Q-series CPU
Q00J/Q00/Q01: Can be applied to Basic model QCPU
Qn(H)
QnPH
QnPRH : Can be applied to Redundant CPU
QnU
QnA: Can be applied to QnA series and Q2ASCPU series
Remote: Can be applied to the MELSECNET/H remote I/O modules.
Each CPU module type name: Can be applied only to the specific CPU module. (e.g.
Q4ARCPU, Q3ACPU)
• User's Manual (Function Explanation, Program Fundamentals) for the CPU
module used
• Q corresponding MELSECNET/H Network System Reference Manual (PLC to
PLC network)
• Q corresponding MELSECNET/H Network System Reference Manual (Remote
I/O network)
• For QnA/Q4AR MELSECNET/10 Network System Reference Manual
• MELSEC-Q/L/QnA Programming Manual (SFC)
: Set by system
: Set by user (in sequence program or test operation at a peripheral device)
indicated only if setting is done by system.
: Set during each END processing
: Set only during initial processing
(when power supply is turned ON, or when going from STOP to
RUN)
: Set only when there is a change in status
: Set when error is generated
: Set only when there is a user request
(through SM, etc.)
: Set when the system is switched
/ corresponding to the ACPU.
format change when there has been a change in contents. Basic
: Can be applied to High Performance model QCPU
: Can be applied to Process CPU
: Can be applied to Universal model Q CPU
Description
MELSEC-Q
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