Mitsubishi Electric MELIPC MI5000 Series User Manual page 259

Appendix 5
The list of special relays contains the following information.
Item
No.
Name
Content
Details
Set by
Do not change the special relay set by system with the operations such as program execution or device test.
Doing so may result in system down or disconnection of communication.
No. Name
SM0 Latest diagnostics error
SM1 Latest self-diagnostic error
SM52 battery low
SM53 AC/DC DOWN
SM80 Detailed information 1:
Flag in use
SM112 Detailed information 2:
Flag in use
SM1536 Cyclic transmission status
SM1540 Data link status
List of Special Relays
Description
Indicates the number of the special relay.
Indicates the name of the special relay.
Indicates the content of the special relay.
Indicates the details of the special relay.
Indicates the timing to set each device by system and/or user.
■Set by
• S: Set by system.
■When to set
• Status change: Set only when the status is changed (by a special relay).
• Error occurrence: Set when an error occurs.
Description
• OFF: No error
• ON: Error
• OFF: No error
• ON: Error
• OFF: Normal
• On: Battery low
• Off: No AC/DC DOWN
detection
• On: AC/DC DOWN is detected
• OFF: Not used
• ON: In use
• OFF: Not used
• ON: In use
• OFF: Cyclic transmission not
executed
• ON: cyclic transmission carried
out
• OFF: All stations normal
• ON: Error station found
Details
• This relay turns ON when the self-diagnoses returns an
error.
• The ON state is maintained even after the error has
been later cleared.
• This relay turns ON when the self-diagnoses returns an
error.
• The ON state is maintained even after the error has
been later cleared.
• This relay switches to ON when the battery voltage of
the MELIPC drops below the specified value.
• Becomes OFF if the battery voltage becomes normal
later.
• This relay synchronizes with BATTERY LED.
This relay switches to ON when a momentary power
failure of 20 ms or less is detected while the AC power
supply module is in use. This relay is reset when power is
turned OFF to ON.
This relay switches to on if the detailed information 1
exists when SM0 switched to ON.
This relay switches to on if the detailed information 2
exists when SM0 switched to ON.
• This relay turns ON when the cyclic transmission
starts.
• This relay is turned OFF when the cyclic transmission
stops.
• This relay turns ON when an error exists even in one
slave station.
• The status of each slave station can be checked in
SD1540 to SD1543 (Data link status of each station).
Appendix 5 List of Special Relays
Set by (when
to set)
S (at error
occurrence)
S (at error
occurrence)
S (at error
A
occurrence)
S (at error
occurrence)
S (status change)
S (status change)
S (status change)
S (status change)
APPX
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