Probing with switchable probe and measured value detection in the drive

Release Note

Function available as of V3.1.3080.05.

Basics

If a measuring probe is used that can be activated/deactivated when no measurement run is executed, the external measuring interface between the CNC and the PLC is used. (See Measure with external measuring hardware)

The CNC informs the PLC of the start and end of a measurement run so that the PLC can activate or deactivate the measuring hardware accordingly.

A possible application is the use of radio measuring buttons to save power.

CNC – PLC

The workflow from the CNC’s point of view is as follows:

The interface between the CNC and the PLC is used to inform about the initialisation, start and end of a measurement run. The probe can then be prepared, enabled or disabled.

The CNC writes each task (HLI_EXT_LATCH_PREPARE_PROBE, HLI_EXT_LATCH_ENABLE_PROBE, HLI_EXT_LATCH_DISABLE_PROBE) with the required parameter number of the probing input and the relevant edge to the interface and sets please_rw = TRUE.

Notice

The interpolator does not move to the measuring block until the PLC acknowledges that probe preparation is completed.

The workflow from the PLC’s point of view is as follows:

After the task “HLI_EXT_LATCH_PREPARE_PROBE“ is received, please_rw is set to FALSE. If the measuring probe is enabled, the PLC signals this to the CNC with done_w = TRUE.
Please note that the PLC must always acknowledge these tasks. At the start of the measuring block the task “HLI_EXT_LATCH_ENABLE_PROBE“ must be acknowledged. After the measurement run is completed, the CNC again informs the PLC with the task "HLI_EXT_LATCH_DISABLE_PROBE"; this task must again be acknowledged by the PLC.

Notice

Before a new measurement run starts, the system waits until the PLC acknowledges the task “HLI_EXT_LATCH_DISABLE_PROBE“.

For more information on the interface structure, refer to the HLI documentation. (See Measure with external measuring hardware)

CNC – DRIVE

Depending on the drive type, the drive must be configured in the drive hardware as described in “Section: Measured value detection”.

Depending on the drive, the measured position is transmitted via the drive interface to the CNC.

Axis parameter

The following axis parameters are required for measuring with the CNC-PLC interface:

Alternatively, the measuring interface can also be enabled in the NC program by the #MEAS command (see [PROG//Extended programming]).