HEIDENHAIN TNC 640, User Manual, Page: 261 / 948

Tools | Tool data
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HEIDENHAIN | TNC 640 | Conversational Programming User's Manual | 10/2017
261
NOTICE
Danger of collision!
During an automatic tool change with
M101
, the control always
retracts the tool in the tool axis first. There is danger of collision
when retracting tools for machining undercuts, such as side
milling cutters or T-slot milling cutters!
Deactivate the tool change with
M102
After the tool change the control positions the tool according to
the following logic, unless otherwise specified by the machine tool
builder:
If the target position in the tool axis is below the current
position, the tool axis is positioned last
If the target position in the tool axis is above the current
position, the tool axis is positioned first
Depending on the NC program, the machining time can increase as
a result of the tool life verification and calculation of the automatic
tool change. You can influence this with the optional entry element
BT
(block tolerance).
If you enter the
M101
function, the control continues the dialog by
requesting
BT
. Here you define the number of NC blocks (1 - 100)
by which the automatic tool change may be delayed. The resulting
time period by which the tool change is delayed depends on the
content of the NC blocks (e.g. feed rate, path). If you do not define
BT
, the control uses the value 1 or, if applicable, a default value
defined by the machine manufacturer.
The higher the value of
BT
, the smaller will be the effect
of an extended program duration through the
M101
function. Please note that this will delay the automatic
tool change!
Use the formula BT = 10: Average machining time
of an NC block in seconds to calculate a suitable
starting value for
BT
. Round up to the next integer. If the
calculated result is greater than 100, use the maximum
input value of 100.
If you want to reset the current age of a tool (e.g. after
changing the indexable inserts), enter the value 0 in the
CUR_TIME column.
The
M101
function is not available for turning tools and
in turning mode.