Ncu Link; Introduction - Siemens SINUMERIK 840D sl Function Manual

B3: Several operator panels connected to several NCUs, distributed systems - only 840D sl
2.5

NCU link

2.5
2.5.1

Introduction

The number of channels or axes per NCU is restricted due to the limitation on memory and
computing capacity elements. A single NCU is not sufficient to fulfill the requirements made
by complex and distributed machines, such as multi-spindle and rotary indexing machines.
For this reason, the control system and closed-loop axis controls are distributed among
several NCUs.
In order to ensure, however, that channels and axes can continue to operate on an
interrelated, cross-NCU basis, the system provides NCU link functionality.
Function extensions
The following applications are possible:
● Cross-NCU interpolation (coupling of setpoints, actual values and VDI signals)
● Real exchange of axes
● Cross-NCU access to axis values and axial system variables
● NCU-user communication supported by NCU link variables
● Generation of alarms on the NCU affected by an irregularity, even if the cause of the
Extended Functions
Function Manual, 09/2009, 6FC5397-1BP20-0BA0
problem is on another NCU.
2.5 NCU link
139