Appendix C: Operation Of Special Devices (M8000 -, D8000 -); Appendix C-1 Special Auxiliary Relay (M8000 To M8511) - Mitsubishi FX3UC SERIES User Manual

FX Series Programmable Controllers
3UC
User's Manual - Hardware Edition

Appendix C: Operation of Special Devices (M8000 -, D8000 -)

The device numbers and functions of the special auxiliary relays (indicated as "special M" in tables) and
special data registers (indicated as "special D" in tables) are shown below.
Note that functions of certain devices vary depending on the series of the PLC.
Do not use the undefined / blank special auxiliary relays and special data registers in the sequence program
since they are occupied by the CPU.
In addition, do not activate or write to the devices with brackets on the first letter such as [M]8000 or [D]8001
in the program.

Appendix C-1 Special Auxiliary Relay (M8000 to M8511)

Number and
Operation and function
name
PLC Status
[M]8000
RUN
RUN monitor
input
NO contact
M8061
Error occurrence
[M]8001
RUN monitor
NC contact
M8000
[M]8002
M8001
Initial pulse
NO contact
M8002
[M]8003 M8003
Initial pulse
NC contact
ON when either M8060, M8061,
[M]8004
M8064,
Error occurrence
M8067 is ON.
[M]8005
ON when battery voltage is
Battery voltage
below the value set in D8006.
low
It is set when battery voltage low
[M]8006
Battery error latch is detected.
ON for 1 scan, when detecting
momentary power failure
[M]8007
Even if M8007 turns ON, PLC
Momentary power
continues to RUN mode in case
failure
duration of power loss is within
period of time specified in D8008.
It is set when momentary power
failure is detected.
[M]8008
If power loss time is longer than
Power failure
period of time specified in D8008,
detected
M8008 is reset and PLC is turned
in STOP mode. (M8000=OFF).
ON when 24V DC power fails in
[M]8009
either powered supply extension
24V DC down
unit
Clock
[M]8010 Not used
[M]8011 ON and OFF in 10 ms cycle
10 ms clock pulse (ON: 5 ms, OFF: 5 ms)
424
Correspond-
ing special
device
1 scan time
M8065, M8066, or D8004
D8005
D8006
D8007
D8008
D8008
D8009
C Operation of Special Devices (M8000 -, D8000 -)
C-1 Special Auxiliary Relay (M8000 to M8511)
→ For detailed explanation, refer to the Programming Manual.
Number and
name
Clock
[M]8012
100 ms clock
–
pulse
[M]8013
1 sec clock pulse
[M]8014
–
1 min clock pulse
M 8015
–
M 8016
M 8017
–
[M]8018
M 8019
Flag
[M]8020
Zero
[M]8021
Borrow
M 8022
Carry
[M]8023
*1
M 8024
*1
M 8025
*1
M 8026
*1
M 8027
M 8028
[M]8029
– Instruction
execution
–
complete
*1. Cleared when PLC switches from RUN to STOP.
Operation and function
ON and OFF in 100 ms cycle
(ON: 50 zms, OFF: 50 ms)
ON and OFF in 1 sec cycle
(ON: 500 ms, OFF: 500 ms)
cycle
ON and OFF in 1 min
(ON: 30 sec, OFF: 30 sec)
Clock stop and preset
For real time clock
Time read display is stopped
For real time clock
±30 seconds correction
For real time clock
Installation detection (Always ON)
For real time clock
Real time clock (RTC) error
For real time clock
ON when the result of addition/
subtraction is 0.
ON when the result of subtraction
is less than the min. negative
number.
ON when 'carry' occurs as a result
of addition or when an overflow
occurs as a result of
operation.
Not used
BMOV direction specification
(FNC 15)
HSC mode
(FNC 53 to 55)
RAMP mode
(FNC 67)
PR mode
(FNC 77)
Interrupt permission during FROM/
TO (FNC 78 and 79) instruction
execution
ON when operation such as DSW
(FNC 72) is completed.
Correspond-
ing special
device
–
–
–
–
–
–
–
–
–
–
–
shift
–
–
–
–
–
–
–