I/O signal or communication line shall be wired at least 100mm 
 away from a high-voltage cable or power line. If not, it may cause 
  abnormal output or operation. 
 Use  PLC  only  in  the  environment  specified  in  PLC  manual  or 
general standard of data sheet. If not, electric shock, fire, abnormal 
operation of the product or flames may be caused. 
 
  Before  installing  the  module,  be  sure  PLC  power  is  off.  If  not, 
electric shock or damage on the product may be caused. 
 
 Be  sure  that  each  module  of  PLC  is  correctly  secured.  If  the 
product is installed loosely or incorrectly, abnormal operation, error or 
dropping may be caused. 
 
 Be sure that I/O or extension connecter is correctly secured. If 
not, electric shock, fire or abnormal operation may be caused. 
 
  If  lots  of  vibration  is  expected  in  the  installation  environment, 
don’t  let  PLC  directly  vibrated.  Electric  shock,  fire  or  abnormal 
operation may be caused. 
 
 Don’t let any metallic foreign materials inside the product, which 
may cause electric shock, fire or abnormal operation..