F7493 fault in siemens sinamics V90 drive indicates an Overflow of the value range for the position actual value. This means the encoder’s calculated absolute position exceeded the maximum 32-bit internal data limit and the drive has lost its absolute reference.
Cause:
The value range (-2147483648 … 2147483647) for the position actual value representation was exceeded. When the overflow occurs, the “referenced” or “adjustment absolute measuring system” status is reset.
- The position actual value (r2521) has exceeded the value range.
- The encoder position actual value has exceeded the value range.
- The maximum encoder value times the factor to convert the absolute position from increments to length units (LU) has exceeded the value range for displaying the position actual value.
Remedy:
If required, reduce the traversing range or position resolution p29247.
Note for case = 3:
If the value for the maximum possible absolute position (LU) is greater than 4294967296, then it is not possible to make an adjustment due to an overflow.
For rotary encoders, the maximum possible absolute position (LU) is calculated as follows:
Motor encoder without position tracking:
- IPOS: p29247 * p29248 * 4096 / p29249 for multiturn encoders
- PTI: 1048576 * p29012[X] * 4096 / p29013 for multiturn encoders
