MC_StepRefPulse¶
Function Block MC_StepRefPulse
This Function Block performs homing by searching for zero pulse (also called Marker or reference pulse) in encoder. The reference pulse appears once per encoder revolution. The advantage in using Reference Pulse for homing is the higher accuracy and precision that can be achieved compared to traditional optical, mechanical or magnetic sensors.
- The axis state is changed to Homing if not already in.
- Home is commanded by user in the desired homing direction at the programmed velocity.
- First occurrence of the Reference Pulse, Homing is finished.
- Torque is limited. Time and Distance Limits can cause error if exceeded.
- This Function modifies actual position and sets to the “SetPosition” input value at the end
- This Function Block clears the Homing State when Done.
It is common that a first approach is performed against a mechanical sensor at higher velocity, and after a Reference Pulse, at a lower velocity. This is a traditional 2-Step homing (Coarse by external Switch in reverse and Fine by Reference Pulse in forward). For ease of use both functions could be grouped together in single Function Block. Advantage having the Function Blocks separate is that any combination is possible (MC_Block and after MC_RefPulse, etc.), stating different velocity and conditions for each Step (higly flexible), without increasing homing Function Block complexity too much.
See the following chapter to check if this Function Block is supported by the used axis implementation: Overview
For this Function Block there is a visualization in the Library MC_Blocks_AC500_V11.
See the following chapter for a list of available data types: Overview