F7442 fault in siemens sinamics V90 drive indicates the Multiturn resolution does not match the modulo range. This means the internal ratio between the encoder’s turns and the programmed axis modulo is not an integer, preventing the drive from correctly restoring position after a power cycle.
Cause:
The ratio between the multiturn resolution and the modulo range (p29246) is not an integer number. This results in the adjustment being set back, as the position actual value cannot be reproduced after power-off/power-on.
Remedy:
Make the ratio between the multiturn resolution and the modulo range an integer number.
The ratio v is calculated as follows:
v = (4096 * p29247 * p29248) / (p29249 * p29246)
