Siemens sinumerik 840D sl Function Manual page 450

Note
The assignment between 2 master axes and a slave axis programmed with TANG( ... ) is
not canceled by TANGOF. Refer to section "Canceling the definition of a follow-up axis
assignment".
2.2.5 Switching off intermediate block generation
In order to stop generating the intermediate block at corners during program execution with
active tangential follow-up control, the TANG() block must be repeated without following
TLIFT().
2.2.6 Canceling the definition of a follow-up axis assignment.
A follow-up axis assignment specified by TANG() remains active after TANGOF. This inhibits
a plane change or geometry axis switchover.
The predefined subprogram TANGDEL is used to cancel the definition of a follow-up axis
assignment so that the follow-up axis can be operated dependent on new leading axes when
a new follow-up axis assignment is defined.
TANGDEL(C)
The existing definition in the example of TANG(A, X, Y) is canceled.
Example for plane change
N10 TANG(A, X, Y, 1)
N20 TANGON(A)
N30 X10 Y20
...
N80 TANGOF(A)
N90 TANGDEL(A)
...
N120 TANG(A, X, Z)
N130 TANGON(A)
...
N200 M30
Special functions: Tangential Control (T3)
Function Manual, 11/2006, 6FC5397-2BP10-2BA0
2.2 Using tangential follow-up control
; delete defined coupling of A to X and Y as leading axes
; A can be coupled to new leading axes
Detailed description
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