Mitsubishi Electric MELIPC MI5000 Series, User Manual

Page: 259 / 320

APPX
Appendix 5 List of Special Relays
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A
Appendix 5
List of Special Relays
The list of special relays contains the following information.
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.
Item Description
No. Indicates the number of the special relay.
Name Indicates the name of the special relay.
Content Indicates the content of the special relay.
Details Indicates the details of the special relay.
Set by 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.
No. Name Description Details Set by (when
to set)
SM0 Latest diagnostics error • OFF: No error
• ON: Error • This relay turns ON when the self-diagnoses returns an
error.
• The ON state is maintained even after the error has
been later cleared.
S (at error
occurrence)
SM1 Latest self-diagnostic error • OFF: No error
• ON: Error • This relay turns ON when the self-diagnoses returns an
error.
• The ON state is maintained even after the error has
been later cleared.
S (at error
occurrence)
SM52 battery low • OFF: Normal
• On: Battery low • 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.
S (at error
occurrence)
SM53 AC/DC DOWN • Off: No AC/DC DOWN
detection
• On: AC/DC DOWN is detected
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. S (at error
occurrence)
SM80 Detailed information 1:
Flag in use • OFF: Not used
• ON: In use This relay switches to on if the detailed information 1
exists when SM0 switched to ON. S (status change)
SM112 Detailed information 2:
Flag in use • OFF: Not used
• ON: In use This relay switches to on if the detailed information 2
exists when SM0 switched to ON. S (status change)
SM1536 Cyclic transmission status • OFF: Cyclic transmission not
executed
• ON: cyclic transmission carried
out
• This relay turns ON when the cyclic transmission
starts.
• This relay is turned OFF when the cyclic transmission
stops.
S (status change)
SM1540 Data link status • OFF: All stations normal
• ON: Error station found • 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).
S (status change)