Mitsubishi FX3G Series User Manual

6 Examination of System Configuration
6.5 Expansion of Main Unit
62
FX3G Series Programmable Controllers
User's Manual - Hardware Edition
6.5.1 When adding input/output extension blocks using the 24V DC service power supply
of the main unit
If extension is not allowed due to restrictions in connection to the main unit described in the preceding
subsection, extension blocks can be added using the 24V DC service power supply of the main unit.
For adding extension blocks using the 24V DC service power supply, it is necessary to examine again
whether extension is possible for all of extension blocks selected in the preceding subsection and extension
blocks to be selected in this subsection.
Note that only up to two network-related special function blocks can be connected including extension to the
main unit.
1 Confirm the priority of all extension blocks to be connected to the main unit.
The priority is set to each extension block to be connected, and required to judge the possibility of
extension to the main unit. The priority is determined by the extension block type without regard to
the connection position.
When the extension power supply unit (FX
3U -1PSU-5V) is used and the nearest upstream unit to
the extension power supply unit is the main unit, the priority should be considered also for input
extension blocks (including the FX
2N -8ER-ES/UL and FX 2N -8ER) extended to the extension power
supply unit.
2 Judge whether extension to the main unit is possible.
Judge the possibility of extension to the main unit for all extension blocks in turn, starting from the
extension block having the highest priority confirmed in step 1. Consider that 16 input/output points
are provided in each of the FX
2N -8ER-ES/UL and FX 2N -8ER. Eight output points have higher prior-
ity over 8 input points. Refer to the preceding subsection for judgment about the possibility of
extension to the main unit.
3 Check whether extension from the 24V DC service power supply is possible.
Check using the quick reference matrix shown below whether the number of points whose exten-
sion is judged as impossible in step 2 can be added using the 24V DC service power supply.
A special function block is handled in the same way as 16 output points.
Example: When 8 input points and 8 output points are connected, the current of the 24V DC service
power supply becomes 150mA or less.
Input extension
block
FX2N-8ER-ES/UL
FX
2N-8ER
Priority 2 Priority 3Priority 1 Priority 4
<Priority>
>>>
Special function
block
Output extension
block
Priority LowPriority High
0 8 16 24 32
Number of added points
Output
Number of
added points
100 016
250 508
400 300 200 100 00
Input
150
(Example)

Mitsubishi FX3G Series Specifications

General

Brand	Mitsubishi
Model	FX3G Series
Category	Controller
Language	English