FX3U-ENET-L USER'S MANUAL - Automation Systems and Controls

SAFETY PRECAUTIONS(Read these precautions before use.)Before installation, operation, maintenance or inspection of this product, thoroughly read through andunderstand this manual and all of the associated manuals. Also, take care to handle the module properly andsafely.This manual classifies the safety precautions into two categories: "DANGER" and "CAUTION."DANGERCAUTIONIndicates that incorrect handling may cause hazardous conditions,resulting in death or severe injury.Indicates that incorrect handling may cause hazardous conditions,resulting in medium or slight personal injury or physical damage.Depending on the circumstances, procedures indicated by CAUTION may also cause severe injury.It is important to follow all precautions for personal safety.Store this manual in a safe place so that it can be taken out and read whenever necessary. Alwaysforward it to the end user.[Design Precautions]DANGERTo prevent malfunctions of the PLC system that may be caused by illegal e-mail, take propercountermeasures (such as virus detection) so that illegal e-mail is not received by the mailserver of this module.If it is necessary to ensure the security of the PLC system against unauthorized access fromexternal devices via the Internet, appropriate measures must be incorporated by the user.When controlling the PLC (modifying data) while it is in operation by connecting computerperipheral devices to the main unit or connecting personal computers to the extension device,make sure to have an interlock circuit outside of the PLC to ensure safe system operation.Do not write any data in the "system area" of the buffer memory of the extension device. Whenwriting a value to the buffer memory including "System Area," pay close attention not to changethe system bit. If data is written to the "system area" or the "use prohibited" signal is output,there is a risk that the PLC system may malfunction.When the program examples introduced in this manual are applied to the actual system,examine the safety of the control in the target system.A - 1 A - 1