Eliminated from:
LenzeElectricalShaft libraryV01.03.04.00 and higher, included as of Engineer HighLevel 2.10 SP2
Behaviour of the new version?
The new version considers an inadvertent turning of the encoder when connecting the mains. After the power has been switched on, the dnPosOut_p position output of the L_EsEncoderConv function block indicates values which match the external position at the dnEncoderIn input of the position encoder if the position restoration has been selected after mains recovery (C5275= 1).
Concerns which products?
All versions of the , included from Engineer HighLevel 2.5 onwards
What happens?
After the power has been switched on, the dnPosOut_p position output of the L_EsEncoderConv function block indicates values that do not match the external position at the dnEncoderIn input of the position encoder.
When does the problem occur?
The problem occurs if restoration of the position after power-on has been selected (C5275=1) in the L_EsEncoderConv function block and the encoder is turned inadvertently during power-off. In this case, the dnPosOut_p position output is sporadically initialised with an incorrect value after the voltage has been restored.
Possibilities of diagnosis?
The internally calculated position ( dnPosOut_p position output of the L_EsEncoderConv, '_p'-Signal function block) diverges from the actual position of the external position encoder (dnEncoderIn input).
Short-term measures/recommendations?
After power-on, calculate the position externally (e.g. in a PLC) and, in the L_EsEncoderConv function block, specify this starting value for the dnPosOut_p position output by means of the bLoadStartPos and dnStartPos_p inputs.
Evaluation:
The L_EsEncoder Conv function block converts the unscaled value of a position encoder (e.g. CAN master value encoder) into the position scaling inside the 9400. This also takes into account any inadvertent turning of the encoder in the power-off state within half the display range. Inadvertent turning in a deenergised state is not detected due to the functional restriction.
As a remedy for this situation, the valid starting value can be determined externally after power-on and can be set by means of the loading function in the L_EsEncoderConv function block.
