Never  connect  the  supply  power  to the  inverter  output  terminals  U,  V 
and W. Power line voltage applied to the output can result in permanent 
damage to the inverter. 
If  frequent  shifting  is  required,  employ  mechanically  connected  switches  or  contactors  to 
ensure that the motor terminals are not connected to the AC power line and inverter output 
terminals simultaneously.