Case description: FANUC system machine tool coordinates suddenly do not follow the programming instructions (that is, the program suddenly runs randomly)
Failure analysis: Generally, the above-mentioned failures occur, and the possibility of the failure caused by the system hardware is very small, so when dealing with similar failures, do not easily *change the system-related hardware. For this type of question, you can generally start the examination and recording from the following aspects:
1) Caused by improper setting of coordinate system G54 or the median value of tool compensation (a few points or input errors)
2) The program of DNC processing is caused by interference during RS-232 transmission, or the transmission software works unstable.
3) The manual absolute value is in an invalid state (that is, G6.2 becomes 1)
4) Handwheel insertion operation was performed in automatic operation mode.
5) Absolute value programming and incremental programming are mixed.
6) Improper operation of personnel (incorrect program selection, incorrect tool compensation settings, incorrect metric and inch systems, polar coordinates, etc.).
7) There is no zero-return operation after power-on, or there is no G28 reference point return for each axis in the engineering program header.
8) MDI mode command coordinate movement, absolute and incremental are related to parameter setting. If the setting is improper, the correct coordinate command cannot be executed.
9) Whether the command is used correctly, such as improper use of G92\G92.1, it is easy to go randomly.
10) The peripheral interference of the machine tool, including the grounding of the machine tool, etc.
11) Misoperation of the operator.