HEIDENHAIN TNC 426 PB/M Technical Manual page 484

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You can define an angle limit for traverse at constant velocity. The size of the

angle depends on the machine drives:

Enter the permissible angle in MP7460.

Realistic input values: 5° to 15°

MP7460 functions without radius compensation at outside corners and with

radius compensation at inside corners. The parameters apply for operation

with both following error and feedforward control.

The contour is machined as shown here:

Axis standstill

If you program M90, the tool velocity in following-error mode is kept constant

at corners without radius compensation. This causes a corner rounding that

varies with the feed rate (see User's Manual).

If you program M112 or M124, defined arcs will be inserted at the corners

regardless of the feed rate (see User's Manual). The rounding arcs generate

twice as many NC blocks, and the feed rate is now only limited by the radial

acceleration.

In MP7680 bit 7, specify whether the rounding arcs should always be

inserted or only when the acceleration from MP1060.x or MP1070 has been

exceeded at the corners.

With MP7680 bit 8, specify whether a rounding arc or a cubic spline is to be

inserted between lines during the M function M112. The cubic spline

produces an additional jerk reduction. But it takes more computing time than

an inserted arc. As of 280 476-xx the feed rate for arcs and splines is

reduced enough to prevent any excessive jerk. This does not apply if F MAX

is programmed.

α = Change of axis direction

Path when MP7460 < α

Path when MP7460 > α

HEIDENHAIN Technical Manual TNC 426, TNC 430