Axis And Spindle Installation; Determining Sampling Interval And Interpolation Time - Siemens SINUMERIK 840C Installation Instructions Manual

09.95
10

Axis and Spindle Installation

10.1

Determining sampling interval and interpolation time

Corresponding data
MD 155 NC MD Position controller basic clock frequency
MD 160 Ratio of interpolation to position control
MD 168 Drive basic cycle time
MD 1396*/MD 466* Position control clock frequency increase axis/spindle
Functional description
MD 155 and MD 168 are used to set the position control basic clock frequency, and MD 160
to set the ratio of the interpolation time to the sampling interval. The objective is to keep both
these times to a minimum.
In order to off-load the CPU as much as possible, axes that are not used for workpiece
machining (auxiliary axes, loader axes) can be controlled at longer intervals. MD 1396* is used
to increase the sampling interval.
The sampling interval is the interval at which the control forwards a new setpoint to the axes
and computes the actual value.
MD466* is valid for the spindle rather than MD1396*.
X
MD 160
=IPO clock frequency
Determination of sampling interval and interpolation time
From software version 3 onwards, the machine data dialog
See Section entitled Machine Data Dialog (MDD).
© Siemens AG 1992 All Rights Reserved
SINUMERIK 840C (IA)
10.1 Determining sampling interval and interpolation time
MD 168
X
MD 155
=Position control basic
clock frequency
X
MD 1396*
=Position control clock
frequency
Axes
handels the standard start-up.
6FC5197- AA50
10 Axis and Spindle Installation
Drive basic cycle time
[62.5 µs]
X
MD 466*
=Position control clock
frequency
Spindles
10–1