discrepancy between commanded and actual on z-axis

I press 'esc' when M0 is the current command. Then I load next .ngc program wich consist of commands for tool length probing (G38.2, G43.1 Z[#5063-#1000] etc.), and the commands to cut the material (g1,g0, etc.). When was processed command g0 z20 (after tool probing and applying of G43.1 Z), z-axis go down to 2.4564 value (the same value was on the screen of AXIS gui), after that any attempts to handle the z-axis were unsuccessful. (z-axis was placed in the wrong values different from commanded) Problem has been resolved when the EMC restarted.

EMC v 2.4.5
Ubuntu hadry heron 8.04 (was installed from EMC 2.3.0 installation disk)

Excuse me for bad English.

But, regardless of active offsets (g54, ...) and offset by Z, when I type g0z20 , digits on screen in gui should be established to "z +20.0000"?

2 andypugh:

During this error, I was in relative coordinates mode.

Thanks.

Is the problem repeatable? A screenshot might contain some information that helps?

No, not very repeatable. It appears rarely, but this is enough to spoil the work. Tomorrow I'll try deliberately call an erroneous situation and will make a screen shot and maybe a photo.