Mitsubishi Electric MELSEC-F FX3G Series User Manual page 94

FX Series Programmable Controllers
3G
User's Manual - Hardware Edition
*1. Input/output occupied points by special function blocks are excluded.
*2. For the input extension block (including the FX
calculate the current consumption of the internal 24V DC. Include the input extension block in
calculation for the nearest main unit or input/output powered extension unit located on the upstream
side to the extension power supply unit.
→ When the main unit is on the upstream side, refer to Subsection 6.5.1 and Subsection 6.5.2.
→ When the input/output powered extension unit is on the upstream side, refer to Subsection 6.6.1
*3. A maximum of 8 special function units/blocks are connectable, including the main unit and the input/
output powered extension unit.
3
Determine whether the devices can be added to the extension power supply
unit.
Calculate the current to confirm whether the selected extension devices can be connected.
1. Calculate the current consumption of the built-in 5V DC power supply.
Capacity of 5V DC
power supply
Extension power
supply unit
3 -1
mA
2. Calculate the available current supply from the internal 24V DC power supply.
Power supply
capacity for internal
24V DC
Extension power
supply unit
3 -2
mA
3. Calculate the available input/output occupied points (excluding the occupied input/output
by special function blocks).
Connectable I/O
occupied points
Extension power
supply unit
3 -3
points
If the calculation result for the 5V DC power supply is a negative value, the current consumption exceeds the
power supply capacity.
If the calculation result for the internal 24V DC is a negative value, the current consumption exceeds the
power supply capacity.
If the calculation result for the number of occupied input/output points is a negative value, the available
number of input/output points is exceeded.
Reconfigure the system with an input/output powered extension unit.
88
Current consumption
Total of current consumed
by extension devices
4 -1
- =
mA
Current consumption
Total of current consumed
by extension devices
-
4 -2
=
mA
Number of I/O
occupied points
Total of I/O occupied points
by extension devices
4 -3
- =
points
6 Examination of System Configuration
6.7 Expansion of Extension Power Supply Unit (FX3U-1PSU-5V)
-8ER-ES/UL and FX
2N
Calculation result
mA
Calculation result
mA
Calculation result
points
-8ER), it is not necessary to
2N
and Subsection 6.6.2.
0mA
0mA
0points