Extension Of The Sag Compensation With Ncu Link - Only 840D Sl - Siemens SINUMERIK 840D sl Function Manual

K3: Compensations
5.4 Interpolatory compensation
compensation tables are referred to below as f tables and their values as f_i(x) (i=number of
table).
The compensation values of f tables are evaluated by multiplying them by other tables. The
latter are referred to below as g tables and their values as g_i(y). The number of f tables and
g tables is equal (four in the example).
In g tables, one compensation value in each table is set to 1 and all the others to 0. The position
of compensation value 1 within the table is determined by the table number. In the first g table,
compensation value 1 is positioned at the first interpolation point and, in the second g table,
at the second interpolation point, etc. By multiplying g tables by f tables, the correct
compensation value in each f table is selected by multiplying it by 1. All irrelevant compensation
values are concealed through multiplication by 0.
Using this scheme, compensation value D
following equation:
D (x/y)=f_1(x)*g_1(y) + f_2(x)*g_2(y) + ...
z
When the compensation value for the actual position of the machine spindle is calculated, the
f table values are multiplied by the g table values according to this rule.
Applied to the example, this means, for instance that compensation value D
calculated by multiplying each of the function values f_i(500) in the f tables by the function
values g_i(300) in the g tables:
D (500/300) = f_1(1000)*g_1(300) + f_2(1000)*g_2(300) + f_3(1000)*g_3(300) +
z
f_4(1000)*g_4(300)
D (500/300) = 0.2*0 + 0.7*1 + 1.2*0 + 1.7*0 = 0.7
z
5.4.4

Extension of the sag compensation with NCU link - only 840D sl

The sag compensation can also be applied to axes in an NCU link group, i.e. if several NCUs
are connected by NCU link.
General parameter assignment
For general parameter assignment, see section "Commissioning (Page 276)".
The parameterization of the input and output axes of a compensation table takes place with
the following system variables:
● $AN_CEC_INPUT_NCU
● $AN_CEC_INPUT_AXIS
● $AN_CEC_OUTPUT_NCU
● $AN_CEC_OUTPUT_AXIS
288
at position (x/y) is calculated according to the
z
Function Manual, 10/2015, 6FC5397-1BP40-5BA3
(500/300) is
z
Extended Functions