Programming instructions

8
2.3 Hardware Components
Main Units
The main unit contains the CPU that provides the processing power that
reads the inputs, solves the logic, and writes to the outputs. The main unit
contains:
1) An integrated power supply that provides power to the CPU, inputs, and a
limited number of connected expansion or special function blocks
2) Integrated inputs. These can be either AC or DC, depending on the model
selected. The largest FX3U main unit has 64 inputs.
3) Integrated outputs. These can be relays, transistors or triacs. The largest
FX3U unit has 64 outputs. In the FX1S and FX1N the ratio of inputs to
outputs is 3 / 2 or 4 / 3. In the FX2N and FX3U line the ratio is 1 / 1.
4) Programming port. This port uses RS-422 as its communication protocol.
The PLC can be programmed through this port, or an HMI (Human-Machine
Interface) can be connected as well.
5) Accessory connection ports. These can be used to connect memory module
or an option board to the main unit.
FX3U
(FX2N is very similar in appearance)
FX2NC Base Unit