Yaskawa NS300 - Manual (Page 5)

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 5 of 16
Programming the NS300/500 Master Ladder
Properly programming the network master controller of the NS300/500 is essential for success when
implementing one of these application modules. Most application issues identified in the field are the result of an
application program that does not adhere to the NS300/500 timing diagrams. This technical note is intended to
explain how the example master ladder program operates, and how it effectively eliminates common
programming mistakes. Following the principles described in this tech note will greatly reduce troubleshooting by
eliminating the majority of application issues. Three main issues are addressed; general program flow, best
practices programming, and proper command bit sequencing and interlocking. After addressing these issues,
specific highlights of the program are also discussed.