HEIDENHAIN TNC 306 Technical Manual - Manual (Page 218)

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TNC 406/TNC 306 10 Handwheel 2/97
MP7670.0 Minimum subdivision factor for handwheel HR 330 and HR 130
Entry range: 0 to 10
Set Reset
M2789 Operating mode "Handwheel" PLC PLC
0=highlight display on "Increment"
1= highlight display on "Interpolation factor"
HR 410
Machine parameter MP7640=2 activates the functions for the HR410 handwheel.
When the control transfers the initializing parameters, it transmits to the handwheel a code that
depends on the value entered in MP7640. After initialization is completed, the handwheel must
answer with a corresponding code. If the code is incorrect, the error message "HANDWHEEL NOT
READY appears.
All keys of the handwheel except for the function keys A, B, and C are evaluated by the NC. All
outputs except O109 to O111 are driven by the NC. The function keys A, B, and C, and the outputs
O109 to O111 must therefore still be evaluated or controlled by the PLC.
Machine parameters MP7670.0 to MP7670.2 determine which subdivision factors are in effect for
low, medium and high speed.
The machine parameters MP7671.0 to MP7671.2 define the speed of the speed levels (low,
medium, high) with the percentage factor from MP1020. The last adjusted speed level (the key last
pressed) remains stored even if power is interrupted.
If the handwheel is active, that is, it the handwheel symbol is shown for one of the axes, the NC will
use the value entered in MP7671.x to calculate the feed rate when the HR 410 axis keys are
pressed. For this reason the axis direction keys on the machine control panel are inhibited whenever
the handwheel axis direction keys are being used.
Assignment of handwheel inputs/outputs for PLC evaluation:
Function key A I173 O109
Function key B I174 O110
Function key C I175 O111
Assignment of handwheel inputs only for information to the PLC:
Slow feed rate I168
Medium feed rate I169
Fast feed rate I170
Axis direction – I171
Axis direction +
I172