Position monitoring function:
Maximum permitted deviation between incremental counted position and absolute
position. 180° el: position monitoring is switched off, neither warning nor error will
be triggered.
For absolute encoders with incremental signals
A warning is triggered in ec02 warning encoder interface if the cyclically deter-
mined deviation between incremental and absolute position is higher than the ad-
justed value in ec32. An error is triggered, if the deviation is repeated several times
in succession.
ec32 max pos error is expressed in (electrical) degrees, since a deviation of just a
few encoder signal periods in combination with high poled synchronous machines
may have been dramatic effects for encoders with low resolution.
The position error in increments is calculated as:
max. position error [inc] = ec29 * 4 [inc] * ec32 [°] / 360° / motor pole pair number
Example: If a max. position error of 20° is electrically adjusted in ec32, the follow-
ing consequences occur for a motor with 3 pole pairs and an encoder with 1024
periods per revolution: The position monitoring triggers a warning message, if the
incremental position has moved from the absolute position by 76 increments or 19
signal periods.
For non-absolute encoders with zero signal
The only difference to position monitoring for absolute encoders is that the incre-
mental position is compared with the zero signal (instead with the absolute posi-
tion).
The first passed zero signal is taken as start value and all subsequently detected
zero signals are compared with it. Even if the same zero signal is always passed
when turning back and forth by just a few degrees.
Special case SinCos encoder with absolute track without zero signal
Here the incremental position is compared with the absolute position. The maxi-
mum deviation is fixed (mechanically) adjusted to 16° and can not be changed.
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