How to connect TX and FX to a terminal box

TX and FX signals can be connected to a terminal box using the appropriate terminal blocks, connectors, and wiring procedures while observing torque and interference precautions.

Connecting FX (Fiber Optic) Ports

FX ports typically use fiber-optic connections with MT-RJ connectors for multimode fiber (50/125 or 62.5/125 µm) or SC/ST connectors depending on the device . To connect FX to a terminal box:

1. Select the correct fiber-optic patch cable that matches the port type (MT-RJ, SC, or ST) and the fiber type (multimode or single-mode) on both ends .
2. Ensure the cable length does not exceed the maximum specified for reliable communication.
3. Use mode-conditioning patch cords if connecting 1000BASE-LX/LH SFP modules to multimode fiber over distances greater than 300 meters .
4. Insert the fiber connectors into the FX port on the device and the corresponding port on the terminal box or patch panel.
5. Avoid bending the fiber sharply and keep it away from electrical cables to prevent signal loss or interference.

Connecting TX (Transmit) Signals

TX signals, often representing digital outputs or serial communication, are connected to terminal blocks as follows:

1. Identify the TX terminals on the terminal block or PLC connector (e.g., X000–X017 for inputs, Y000–Y017 for outputs on FX series PLCs), .
2. Use crimp-style terminals of the recommended dimensions and insert the wires into the terminal block .
3. Tighten the terminal screws to the specified torque (0.5–0.8 N·m or 4.4–7.1 lbf·in) to ensure a secure connection without damaging the unit .
4. Keep TX wiring separate from power cables to avoid noise interference and voltage drops .

FX-PCV Controller Example

For FX-PCV controllers, the 24 VAC supply power is connected to a two-terminal plug on the terminal block, with HOT and COM wires from the transformer . Ensure uniform phasing across network devices to reduce noise and ground loop issues. Stray wire strands should be avoided to prevent short circuits .

Safety and Best Practices

• Do not share trunking ducts with power cables to prevent interference .
• Verify connector types and pinouts before connecting to avoid damage .
• Follow manufacturer wiring diagrams for both FX and TX connections to ensure proper operation . By following these steps, TX and FX signals can be safely and reliably connected to a terminal box for PLC or network applications.