Appendix 6 Special Relay (Sm) List - Mitsubishi Electric MELSEC-L SSCNETIII/H User Manual

Appendix 6
The special relay (SM) is an internal relay whose application is fixed in the programmable controller. However, it can
be turned on/off as needed to control the head module.
The following table shows how to read the special relay list.
Item
No. Special relay number
Name Special relay name
Description Contents of special relay
Details Detailed description of special relay
Set side and set timing of special relay
<Set by>
• S: Set by system.
• U: Set by the user (via network or by test operation of GX Works2).
• S/U: Set by both system and user.
Set by
<Set timing>
(Set timing)
The following shows the set timing when the special relay is set by system.
• Initial: Set during initial processing (after power-on or reset).
• Status change: Set when the operating status is changed.
• On error: Set if an error occurs.
• Write: Set when data is written to the module.
Do not change the value of any special relay set by the system using test operation, etc. Doing so may result in system down
or communication failure.
Special Relay (SM) List
Description
APPENDICES
A
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