MC_TouchProbe

The MC_TouchProbe FB records an axis position when a trigger event occurs. The measurement channel and method (rising or falling edge of the trigger signal) are defined via the reference for the trigger signal source.

Block diagram

Parameters of the FB

VAR_IN_OUT
	Axis	AXIS_REF	Axis reference
	TriggerInput	TRIGGER_REF	Reference to the trigger signal source (see chapter 1.2.1).
VAR_INPUT
	Execute	BOOL	Starts touch probe recording at rising edge.
VAR_OUTPUT
	Done	BOOL	Trigger event recorded.
	Busy	BOOL	Is TRUE, while it is waited for the trigger event.
	Error	BOOL	Indicates if an error has occurred.
	ErrorID	WORD	Error identification.
	CommandAborted	BOOL	Command is aborted by another command (MC_AbortTrigger).
	RecordedPosition	LREAL	Position where trigger event occurred. Default unit [0,1µm or 10-4 °]

Behavior of the FB

A measurement command is issued only when the axis is in the ‘Standstill’ or ‘Continuous Motion’ or ‘Discrete Motion’ or ‘Synchronized Motion’ or ‘Stopping’ state. Moreover, no measurement command must be active in the measurement channel specified by ‘trigger_input’. The measurement channel must therefore be in the ‘TP_IDLE’ state. If this is not the case, the ‘Error’ output is set to TRUE and ‘ErrorID’ indicates an error value that designates the state the axis is currently in.
If a measurement command in a measurement channel is active, no further measurement command in relation to this measurement channel can be sent. Therefore, the FB cannot be retriggered. If it is nevertheless commanded, the ‘Error’ output becomes TRUE and reports the value 44009 (ERR_PO_AX_TPROBE_RETRIG) at ‘ErrorID’.
Errors are also generated, if, while measuring is active, the axis reference, the measurement channel or the measurement type has changed. These errors' codes have the values:

44001, , (ERR_PO_AX_REF_CHG_WHILE_ACTIVE),
44011 (ERR_PO_AX_INPREF_TPCH_CHW_ACTIVE),
44012 (ERR_PO_AX_INPREF_TPMD_CHW_ACTIVE).