IEC RETAIN variables are not supported on Unidrive M for saving non-volatile data through power-down/ up. This means that code such as the following will not compile:
// Save position on power-down. THIS WILL NOT COMPILE.
VAR RETAIN
POSITION : DINT;
END_VAR
However, Unidrive M400 contains a number of non-volatile parameters in its Application menus - menu 18 and 20. These values are a mixture of PS (power-down save) parameters that are automatically saved when the drive powers off, and user-saved parameters that are saved on command by the user. Please read the Unidrive M user guide for more details.
See Also