37
FX
3U
/FX
3UC
Series Programmable Controllers
Programming Manual - Basic & Applied Instruction Edition
2 Overview (Sequence Program)
2.7 Types and Setting of Parameters
1
In
troduct
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Ov
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In
st
ru
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Li
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D
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De
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Speci
fied t
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D
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Bef
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Pr
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Bas
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FNC0
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-FNC0
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FNC1
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-FNC1
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M
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FNC
20-
FNC
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Ar
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2.7
Types and Setting of Parameters
Setting of parameters means setting the environment where the PLC operates.
Almost all FX
3U
/FX
3UC
PLCs can be used with factory default values. When it is necessary to add optional
memory, set the comment capacity, set the communication condition for serial ports, etc., change the
parameter settings by a programming tool such as personal computer.
2.7.1
Parameter list
The following items may be set in the parameter settings.
Classification
Item
Description
Memory
capacity
Memory
capacity
This parameter specifies the maximum value for the number of steps to which a
sequence program can be input.
1) The upper limit is determined by the capacity of the built-in memory or optional
memory.
2) The program memory, file register, comment area, and other special setting
capacities are contained in this memory capacity.
Comment
area
This parameter incorporates comments into the program memory.
1) Because comments remain in the PLC, the contents can be easily understood at the
time of maintenance.
2) Up to 50 comments can be input when one block is specified, but the program
memory capacity is reduced because the comment area requires 500 steps in the
memory capacity.
File register
This parameter incorporates data registers into the program memory.
1) A sequence program and control data such as machining set values can be handled
together, which is convenient.
2) Up to 500 file registers can be created when one block is specified, but the program
memory capacity is reduced because file registers require 500 steps in the memory
capacity.
Other special
setting
capacity
1) This parameter sets whether or not the special block/unit initial value setting
function is used.
When this function is used, the program memory capacity is reduced because this
function requires 4000 steps (8 blocks) in the memory capacity.
2) This parameter sets whether or not the positioning setting (constants and setting
table) in TBL (FNC152) instruction is used. When this setting is used, the program
memory capacity is reduced because this setting requires 9000 steps (18 blocks) in
the memory capacity.
Device setting
Latch range
setting
This parameter enables to change the latched (battery backed) device range and the
non-latch device range inside the PLC.
I/O assignment
setting
I/O
assignment
setting
This setting is not written to the PLC.
When the I/O range is set according to the system configuration, however, inputs and
outputs are checked by the program check in GX Developer.
Special unit
setting
This parameter sets the initial values of the buffer memory (BFM) for each special block/
unit number.
It is necessary to set the memory capacity.
PLC system
setting (1)
[PLC mode]
Batteryless
mode
This parameter sets the PLC operation mode without a battery.
When the baterryless mode is set, detection of battery voltage low level error is stopped
automatically, and consequently, contents of latched (battery backed) devices becomes
inconsistent and are initialized automatically.
Modem
initialization
This parameter automatically sends a specified AT command as an initialization
command to a modem connected to the serial port.
RUN terminal
input setting
This parameter sets whether one input terminal in the PLC is used for RUN input.
RUN terminal
input number
This parameter specifies the input number of the RUN input described above within the
range from X000 to X017.
PLC system
setting (2)
[Serial
communication]
Serial port
operation
setting
This parameter corresponds to the following settings by specifying each contents on the
PC screen:
Setting of communication format (D8120, D8400 and D8420)
Setting of station number (D8121 and D8421)
Setting of timeout check (D8129, D8409 and D8429)
