HEIDENHAIN iTNC 530 Service Manual page 59

Special case: Absolute multiturn rotary encoder
The control saves an overflow (more than 4096 revolutions of the encoder) internally.
Additionally, the number of traversed sectors (1 sector = 256 revolutions) is saved.
After the drives are switched on, the current sector is compared to the saved sector.
When the motor is switched on and to the switch-off position two complete sectors are in
between (further than the sector "after next"), the error message Switch-off pos. <axis> unequal
ENDAT is immediately displayed after the drives are switched on.
It is possible that a pop-up window appears with the information that there is a difference
between switch-on and switch-off position by more than the value in MP1146.x. If the motor
is at the correct position, the message can be confirmed with the YES soft key.
MP1146.x
Input:
May 2006
Switch-off position in
Error!
1 sector
(= 256 revolutions)
Caution
The error has to be eliminated!
It is assumed that after restarting the control the number
of revolutions is correct again.
Difference between switch-off position and position read in via the EnDat
interface
0.0000 to 300.0000 (mm) or (°)
0: No difference permitted
this sector
Error!
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