HEIDENHAIN TNC 306 Technical Manual - Manual (Page 502)

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TNC406/TNC 306 Update Information No. 11
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The following machine parameters and PLC words are applicable when MP2081=1:
MP 2133 Retraction velocity for short circuit during erosion; short circuit is quickly detected
through X12. (MP 2133 has no function if = 0.)
MP 2141 Free-run feed rate forward if analog voltage has crossed the threshold.
MP 2142 Feed rate for gap control at SV=100%
W520 Threshold for positioning with free-run feed rate from MP2141 value range 0 to 500
(corresponds to the voltages 0 to 5 V).
W522 Factor for gap feed rate backwards
Value range 0 to 1000 (corresponds to factor 0.0 to 10.0).
W524 Nominal value of sparking gap (GV)
Value range 0 to 500 (corresponds to 0 to 5 V
• New M function M93, backward positioning
The new M function M93 was introduced to make it simpler to program the OEM cycle
necessary for erosion of vector cavities and star cavities. Erosion blocks (also circle / helix) that
are programmed with this M function are automatically repositioned to the starting point after
execution (as in the disk cycle). M93 is permitted only when M36 is active.
• Improvement of the function for erosion with time limit
Cycle 2 (eroding with time limit) is also effective for erosion blocks with M93.
• New marker M2189
M2189 is set by the NC if an error message is displayed from the PLC by error markers M2924
to M3123. PLC error messages are deleted by resetting the error marker or by pressing the CE
key.
• The input range for MP 1060.x (acceleration) was changed to the values 0.01 to 9.0.
• The input range for MP 330.x (resolution of encoder) was changed to the values 1 to 360 ([µm or
1/1000 degrees] per encoder period. For square-wave inputs, the encoder must be equipped
with a 5-fold EXE if it has distance-coded reference marks (MP1350). If an angular axis is
connected to a square-wave input, the encoder must output 90 000 pulses per revolution (ppr) or
a divisor thereof.
Example:
For a rotary encoder and 5-fold EXE (square-wave input): (RON 275 C or ROD 270 C)
18 000 ppr * 5 = 90 000 ppr
MP330 = 4 (min. value for square wave)
9 000 ppr * 5 = 45 000 ppr MP330 = 8
If an angular axis is connected to sinusoidal inputs, the encoder must output a total of 360 000 or
a divisor thereof:
ROD 4xx with 2000 ppr * transmission ratio 180 (no EXE)
= 360 000 MP330=1
ROD 4xx with 1000 ppr * transmission ratio 180 (no EXE) = 180 000 MP330=2
ROD 4xx with 1000 ppr * transmission ratio 90 (no EXE) = 90 000 MP330=4
ROD 4xx with 3000 ppr without transmission ration = 3 000 MP330=120