Yaskawa NS300 - Manual (Page 9)

Subject: Technical Note Product: NS300/NS500 Doc#: EM.MCD.05.106
Title: NS300/500 Master Ladder Example
Doc#: Copyright Yaskawa Electric America
©2004
May 9, 2007 Page 9 of 16
The last recommended programming practice is to force off any non-utilized command bits. Two bits are provided
in order to modify the motion command by indicating a direction, using the DIR bit, or indicating that the move
should be absolute or incremental, using the INC bit. These bits are only valid for selected commands, and
otherwise have no significance. When a command is selected that renders these specific bits inactive, they
should be set off. This is shown below in line 41, which controls the DIR bit.
Fig 4. DIR Bit Circuit
The PLC_DIR bit commands the DIR coil. However, the DIR coil is only valid during feed, step, station, or point
table commands. If the PLC_DIR is set, but the current command is not of the commands that can utilize the DIR
command, then this bit is left off and properly follows the recommended practice.