Filter
Top Products
34
FX3G/FX3U/FX3UC Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
2 Overview (Sequence Program)
2.6 Program Memory and Devices
2.6.2 Memory operations and latched (battery or EEPROM backed) devices
(power ON/OFF and RUN/STOP)
1. Backup operation
The operations of the data memory, bit device memory and program memory in FX3G/FX3U/FX3UC PLCs are classified
as shown below:
1) Types of program memory
2) Types of word device memory
a) FX
3U/FX3UC PLC
*1. The contents of the program memory and device values are not backed up correctly in FX
3U
/FX
3UC
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.
→ For special data registers, refer to Chapter 37.
*4. An optional memory cassette is required.
Item Power OFF
Power
OFF→ON
STOP→RUN RUN→STOP
Parameter
Does not change.
*1
Sequence program
Does not change.
*1
Comment
Can be secured by
parameter setting.
Does not change.
*1
File register
Does not change.
*1
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
Does not change.
*2
File type
Does not change.
*1
Special type Cleared.
Set to initial
values.
*3
Does not change.
*3
Extension register (R)
Latched (battery
backed) type
Does not change.
*2
Extension file register
(ER)
*4
File type Does not change.
Index register (V, Z) V, Z Cleared. Does not change.
Timer present value
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)
Does not change.
*2
Retentive type for 1 ms
(battery backed)
Does not change.
*2
Counter present value
register (C)
General type Cleared.
Does not change. Cleared.
Does not change while M8033 is ON.
Latched (battery
backed) type
Does not change.
*2
High speed type
(battery backed)
Does not change.
*2
Clock data
Present value
(battery backed)
Does not change.
*2