Memory Operations And Latched (Battery Backed) (Power On/Off And Run/Stop) - Mitsubishi Electric MELSEC FX3U Programming Manual

FX /FX /FX Series Programmable Controllers
3G 3U 3UC
Programming Manual - Basic & Applied Instruction Edition
2.6.2 Memory operations and latched (battery backed)
(power ON/OFF and RUN/STOP)
1. Backup operation
The operations of the data memory, bit device memory and program memory in FX
classified as shown below:
1) Types of program memory
Parameter
Sequence program
Comment
File register
2) Types of word device memory
a) FX /FX
3U
Data register (D)
Extension
(R)
Extension file
register (ER)
Index register (V, Z) V, Z
Timer present value
register (T)
Counter present
value register (C)
Clock data
*1. The contents of the program memory and device values are not backed up correctly in FX
PLCs when the battery voltage becomes lower than the holding voltage if a memory cassette is not
attached.
*2. Device values are not backed up correctly when the battery voltage becomes lower than the holding
voltage.
*3. Some devices are cleared when the PLC status switches from STOP to RUN.
*4. An optional memory cassette is required.
36
Item
Can be secured by
parameter setting.
PLC
3UC
Item
General type
latched (battery
backed) type
File type
Special type
register latched (battery
backed) type
File type
*4
For 100 ms
For 10 ms
Retentive type for 100 ms
(battery backed)
Retentive type for 1 ms
(battery backed)
General type
latched (battery
backed) type
High speed type
(battery backed)
Present value
(battery backed)
Power
Power OFF
OFF→ON
Does not change.
Does not change.
Does not change.
Does not change.
Power
Power OFF
OFF→ON
Cleared.
Does not change.
Does not change.
Set to initial
Cleared.
*3
values.
Does not change.
Does not change.
Cleared.
Cleared.
Cleared.
Does not change.
Does not change.
Cleared.
Does not change.
Does not change.
Does not change.
→ For special data registers, refer to Chapter 37.
2 Overview (Sequence Program)
2.6 Program Memory and Devices
/FX /FX
3G 3U 3UC
STOP→RUN RUN→STOP
*1
*1
*1
*1
STOP→RUN RUN→STOP
Does not change. Cleared.
Does not change while M8033 is ON.
*2
*1
*3
Does not change.
*2
Does not change.
Does not change. Cleared.
Does not change while M8033 is ON.
Does not change. Cleared.
Does not change while M8033 is ON.
*2
*2
Does not change. Cleared.
Does not change while M8033 is ON.
*2
*2
*2
3U
PLCs are
/FX
3UC