Mitsubishi Electronics FX3G User Manual
38
FX
3S
/FX
3G
/FX
3GC
/FX
3U
/FX
3UC
Series
Programming Manual - Basic & Applied Instruction Edition
2 Overview (Sequence Program)
2.6 Program Memory and Devices
c) FX
3U
/FX
3UC
PLCs
*1.
Device values are not backed up correctly when the battery voltage becomes lower than the holding voltage.
*2.
The contents of the program memory and device values are not backed up correctly when the battery voltage
becomes lower than the holding voltage if a memory cassette is not attached.
*3.
Some devices are cleared when the PLC status switches from STOP to RUN.
→ For special data registers, refer to Chapter 37.
*4.
An optional memory cassette is required.
Caution
Programs (when a memory cassette is not attached), latched (battery backed) type device values and clock data is not
backed up correctly when the battery voltage becomes low due to expiration of the battery life or another reason.
In such a case, clear latched (battery backed) type devices, transfer programs again (when a memory cassette is not
attached), and then set initial values and clock data if necessary.
backed up correctly when the battery voltage becomes low due to expiration of the battery life or another reason.
In such a case, clear latched (battery backed) type devices, transfer programs again (when a memory cassette is not
attached), and then set initial values and clock data if necessary.
→ For a rough guide to the life and replacement of the battery, refer to the PLC User’s Manual
[Hardware Edition].
→ For the latched type device initialization method, refer to Subsection 2.6.5.
Item
Power OFF
Power
OFF
→ON
STOP
→RUN
RUN
→STOP
Data register (D)
General type
Cleared.
Does not change.
Cleared.
Does not change while M8033 is ON.
Latched (battery
backed) type
backed) type
Does not change.
*1
File type
Does not change.
*2
Special type
Cleared.
Set to initial
values.
*3
Does not change.
*3
Extension register (R)
Latched (battery
backed) type
backed) type
Does not change.
*1
Extension file register
(ER)
(ER)
*4
File type
Does not change.
Index register (V, Z)
V, Z
Cleared.
Does not change.
Timer present value
register (T)
register (T)
For 100 ms
Cleared.
Does not change.
Cleared.
Does not change while M8033 is ON.
For 10 ms
Cleared.
Does not change.
Cleared.
Does not change while M8033 is ON.
Retentive type for 100 ms
(battery backed)
(battery backed)
Does not change.
*1
Retentive type for 1 ms
(battery backed)
(battery backed)
Does not change.
*1
Counter present value
register (C)
register (C)
General type
Cleared.
Does not change.
Cleared.
Does not change while M8033 is ON.
Latched (battery
backed) type
backed) type
Does not change.
*1
High-speed type
(battery backed)
(battery backed)
Does not change.
*1
Clock data
Present value
Does not change.
*1