ShaftMechRefPosition

General

Functional Description

ShaftMechRefPosition represents the reference position of the drive shaft (gear box output side) in units. The dead time ShaftRefDelay is compensated starting from MechRefPosition. The YOffsetPosition from the Y offset generator is taken into account. Coordinate displacements with SetPos (FC_SetposDual(), FC_SetposGroup(), FC_SetposSingle()) affect this parameter. The parameter Direction has to be taken into account during the interpretation of ShaftMechRefPosition.

The value of ShaftMechRefPosition is calculated once every Sercos cycle (CycleTime).

In relation to the reference position on the drive shaft, there is no delay. However, an acceleration-proportional detected error occurs during the compensation of the dead time.

NOTE: If ControllerEnable is disabled, the value of ShaftMechPosition is cyclically copied to ShaftMechRefPosition. Thus, the drive is automatically synchronized to the position for the next release. If ControllerEnable is switched off while the drive is still in motion a jump occurs in ShaftMechRefPosition. The drive does not react to this jump because it no longer follows the set-point settings when ControllerEnable is switched off.

NOTE: The parameter value is transferred from the slave to the master via the parameter channel of the Sercos by every access. Typically, this takes about 10 ms. However, up to 1 s can be realized if large amounts of data are transferred on the parameter channel. If the Sercos bus is in phase 0 or 1, then a default value is indicated here. If the Sercos bus is in phase 3 or 4, then the parameter value is transferred and indicated. In the Sercos phase 2, the parameter can be read through the application.