Siemens SINUMERIK 840D Programming Guide

10
08.97 Motion-Synchronous Action
10.4 Actions within s
y
nchronized actions
10
840D
NCU 572
NCU 573
840Di

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SINUMERIK 840D/840Di/810D/FM-NC Programming Guide Advanced (PGA) – 04.00 Edition
10-369
10.4.11 Adaptive control (multiplicative)
Programming example
Influence the programmed feedrate by
multiplication
The aim is to influence the programmed feedrate by
multiplication. The feedrate must not exceed certain
limits – depending on the load on the drive:
•
The feedrate is to be stopped at a drive load of
80%: Override = 0.
•
At a drive load of 30% it is possible to traverse at
programmed feedrate: Override = 100%.
•
The feedrate can be exceeded by 20%:
Max. override = 120%.
Upper limit
Lower limit
30 80
100
120
160
Load
[ ]
%
OVR
[ ]
%
1. Polynomial definition
Determination of the coefficients
y = f(x) = a
0
+ a
1
x + a
2
x
2
+ a
3
x
3
a
1
= –100%/(80–30)% = –2
a
0
= 100 + (2*30) = 160
a
2
= a
3
= 0 (not quadratic or cubic element)
Upper limit = 120
Lower limit = 0
Therefore:
FCTDEF(2,0,120,160,-2,0,0)
2. Activate AC control
ID=1 DO SYNFCT(2,$AC_OVR,$AA_LOAD[x])
;Read the current axis load (% of the max. drive current ) via $AA_LOAD[x],
calculate the feedrate override with the polynomial defined above.

Siemens SINUMERIK 840D Specifications

General

Series	SINUMERIK 840D
Axes	Up to 31
Channels	Up to 10
Operating System	Windows-based
Power Supply	24 V DC
Control Unit Type	CNC
Interface	Ethernet, PROFIBUS
Display	TFT color display
Interpolation	Spline
PLC	Integrated PLC
Data Storage	CompactFlash, USB