HEIDENHAIN TNC 306 Technical Manual - Manual (Page 230)

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TNC 406/TNC 306 14 Electrode changer 2/97
The flowchart for this Electrode Changer example is written in the form of modules which are listed
below:
TOOL CALL Automatic Electrode Change
REPLACE OLD TOOL Return current electrode to original rack location
PLC POS. NEUTRAL Move to clearance position in X, Y and Z
SELECT NEW TOOL Take new electrode from defined rack position
POC. REG Determine electrode rack position
PLC POS. POC 1/2/3/4/5 Move to defined rack position
PLC POS. Z DOWN Move to Z axis position for electrode change
PLC POS. Z UP Move to Z axis clearance position
For the electrode change, five conditions need to be considered:
1 T-code > Tmax
=> Error Message: "INCORRECT TOOL NUMBER"
2 0 < T-code < = Tmax and SPIREG = 0
=> No current tool, select new tool only
3 T-code = 0 and 0 < SPIREG <= Tmax
=>Replace old tool, no new tool
4 0 < T - code <= Tmax and 0 < SPIREG <= Tmax
=> Replace old tool, select new tool
5 T-code = SPIREG
=> No T-code is sent from the NC to the PLC or direct acknowledgment sent from
the PLC
Note: T-code = New tool number transmitted to W262
Tmax = Maximum tool number (i.e. 5)
SPIREG = Current tool number