Specifications

15
2. Replacement of FX2N series
1
Introduction
2
Replacement of FX2N series
3
Replacement of FX2NC
series
4
Program changeover method
A
Models affected by production termination
B
Related manuals
C
Frequently asked questions
2.3.2 Cautions about hardware
z Comparison of FX2N series and FX3U series and cautions for replacement
This is a list of hardware cautions. When performing replacement, please refer to the manual of each
model and conrm details list here.
 Hardware differences of FX
2N series and FX3U series, and cautions
No. Item
Difference
Caution
FX
2N series FX3U series
1
Pitch of mounting
holes in lateral
direction
Overall dimension
-10mm
Different depending
on the number of
I/O points.
Mounting hole positions in the
lateral direction are different
(see Fig. 1. Outline Drawing on
the next page).
2 Input wiring
FX
2N Japan type
models are sink
input only.
FX3U has standard
sink/source input.
Wiring to the S/S terminal is
needed for the FX3U (see Fig. 2.
on the next page).
3
Battery and mounting
position
F
2-40BL,
lithium thionyl
chloride primary
battery
FX3U-32BL,
lithium manganese
dioxide primary
battery
Type name (model) is different.
Mounting position is different.
4 Battery voltage
Nominal voltage
3.6V
Nominal voltage
3.0V
Be careful when using special
device D8005 (battery voltage).
5
Input hardware lter
(when digital lter is
zero)
• High-speed counter
• Input interrupt
function
• Pulse catch function
X0, X1: 20μs
X2 to X7: 50μs
X10 to X17: 200μs*
*16 I/O point main
unit: 10ms
X0 to X5 : 5μs
X6, X7: 50μs
X10 to X17: 200μs*
*16 I/O point main
unit: 10ms
Noise, not detected in FX2N,
may affect input of FX3U.
If necessary, implement a noise
countermeasure external to the
main unit.
6
FX
1, FX2 series
expansion
Expansion possible
using
FX2N-CNV-IF.
Expansion not
possible.
Using FX2N or FX3U series
replacement models.
7
Terminal end resistance
of 485-BD, 485ADP
Packaged together
with BD and ADP,
to be selected and
installed.
Built into BD and
ADP, selectable
using a switch.
In FX3U, the resistance value
can be selected using a built-in
switch.
8
Wire size of 485-BD,
485ADP
AWG26 to 16 AWG22 to 20
Wire size is different. A large
wire size may not be usable in
FX3U. (See Table 1. Cable size,
page 17).