Programming instructions

ADT-CNC4620 Programming Manual
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1.6. Conversion between imperial and metric system*
Set the unit to imperial or metric with G code (G20, G21).
System G code Minimum unit
Imperial G20 0.0001 inch
Metric G21 0.0001mm
The G code for imperial and metric switch should be placed in front of the program. Use
separate block instruction before setting the coordinate system. The unit system of the
following values changes according to the G code for imperial and metric switch.
(1) Feeding speed instruction value expressed with F.
(2) Instruction value related to position
(3) Compensation
(4) The value of one scale of the Handwheel pulse generator
(5) Movement of single step
(6) Part value of the parameter
Note:
1. When the system is electrified, the G code for imperial and metric switch is same as
before the power supply is cut off
2. In the program, do not change G20, G21
3. If the mechanical unit system is different from the input unit system, the maximum
error would be 0.5 of minimum movement unit, and the error won’t be accumulated.
4. When imperial input (G20) and metric input (21) are switched, the offset should
comply with the new setting of the input unit.
1.7. Program constitution
To complete automatic processing of the part, you need to write the part program (the program)
according to the instruction format of the CNC system, which will execute the program and
complete the controls such as machine tool feeding, principal axis start/stop, tool selection, cooling
and lubrication, and thus finish the part processing.
For example:
Fig. 1-7