Siemens SINUMERIK 840Di sl Function Manual page 52

Detailed description
2.4 Actions in synchronized actions
Additive feedrate control
In case of additive control, the programmed value (F word with respect to Adaptive Control)
is compensated by an additive factor. F
The following are set, for instance, as 'real-time variable output':
$AC_VC
$AA_VC[axis]
Example of additive control of path feedrate
The programmed feedrate (axial- or path-related) must be subject to additive control by the
(positive) X axis current (e.g. infeed torque). The operating point is set to 5 A. The feedrate
may be altered by ±100 mm/min. The magnitude of the axial current deviation may be ±1 A.
Figure 2-5
Determination of the coefficients, see also Chapter "FCTDEF":
y = f(x) = a
a = 100mm / (1min*A)
1
a = -100 → Control constant
1
a = -(-100)*5 =500
0
a = 0 (not a square component)
2
a = 0 (not a cubic component)
3
Upper limit = 100
Lower limit = -100
The polynomial to be defined (no. 1) is thus as follows:
FCTDEF(1, -100, 100, 500, -100, 0, 0)
This function completely describes the Figure "Example of additive control".
52
additive path-feed offset,
additive axial feedrate override
Example of additive control
+ a x +a x + a x
2 3
0 1 2 3
= F + F
active programmed AC
Function Manual, 11/2006, 6FC5397-5BP10-2BA0
Synchronized actions