Installing the PLC

The FX2N equipment is designed to be easy to install。 You can use the mounting holes to attach the modules to a panel, or you can use the built-in clips to mount the modules onto a standard (DIN) rail。 The small size of the FX2N allows you to make efficient use of space。

Guidelines for Installing FX2N Devices

You can install an FX2N either on a panel or on a standard rail, and you can orient the FX2N either horizontally or vertically。

Separate the FX2N Devices from Heat, High Voltage, and Electrical Noise

As a general rule for laying out the devices of your system, always separate the devices that generate high voltage and high electrical noise from the low-voltage, logic-type devices such as the FX2N。

When configuring the layout of the FX2N inside your panel, consider the heat-generating devices and locate the electronic-type devices in the cooler areas of your cabinet。 Operating any electronic device in a high-temperature environment will reduce the time to failure。

Consider also the routing of the wiring for the devices in the panel。 Avoid placing low voltage signal wires and communications cables in the same tray with AC power wiring and high-energy, rapidly-switched DC wiring。

Provide Adequate Clearance for Cooling and Wiring

FX2N devices are designed for natural convection cooling。 For proper cooling, you must provide a clearance of at least 25 mm above and below the devices。 Also, allow at least 75 mm of depth。

Caution 

For vertical mounting, the maximum allowable ambient temperature is reduced by 10 degrees C。 Mount the FX2N CPU below any expansion modules。

When planning your layout for the FX2N system, allow enough clearance for the wiring and communications cable connections。 For additional flexibility in configuring the layout of the FX2N system, use the I/O expansion cable。

Power Budget

All FX2N CPUs have an internal power supply that provides power for the CPU, the expansion modules, and other 24 VDC user power requirements。

The FX2N CPU provides the 5 VDC logic power needed for any expansion in your system。 Pay careful attention to your system configuration to ensure that your CPU can supply the 5V power required by your selected expansion modules。 If your configuration requires more power than the CPU can supply, you must remove a module or select a CPU with more power capability。 

All FX2N CPUs also provide a 24 VDC sensor supply that can supply 24 VDC for input points, for relay coil power on the expansion modules, or for other requirements。 If your power requirements exceed the budget of the sensor supply, then you must add an external 24 VDC power supply to your system。 Refer to Appendix A for the 24 VDC sensor supply power budget for your particular FX2N CPU。

If you require an external 24 VDC power supply, ensure that the power supply is not connected in parallel with the sensor supply of the FX2N CPU。 For improved electrical noise protection, it is recommended that the commons of the different power supplies be connected。

Guidelines for Grounding and Wiring

Proper grounding and wiring of all electrical equipment is important to help ensure the optimum operation of your system and to provide additional electrical noise protection for your application and the FX2N。

Prerequisites

Before you ground or install wiring to any electrical device, ensure that the power to that equipment has been turned off。 Also, ensure that the power to any related equipment has been turned off。

Guidelines for Isolation

FX2N AC power supply boundaries and I/O boundaries to AC circuits are rated 1500 VAC。

These isolation boundaries have been examined and approved as providing safe separation between AC line and low voltage circuits。

All low voltage circuits connected to an FX2N, such as 24V power, must be supplied from an approved source that provides safe isolation from AC line and other high voltages。 Such sources include double insulation as defined in international electrical safety standards and have outputs that are rated as SELV, PELV, Class 2, or Limited Power according to various standards。