Calibration

CALI_PLC_CAM / CALI_HW_SYNC / SET_CALIBRATION / SET_CALIBRATION_AUTO / CLEAR_CALIBRATION:

The simplest calibration case is calibration by cam only (connected to one digital input).

Here, the motor travels in the 1^st step with velocity 1 (Index 0x8020:09) in direction 1 (Index 0x8021:13) towards the cam. Subsequently, in the 2^nd step, it travels with velocity 2 (Index 0x8020:0A) in direction 2 (Index 0x8021:14) away from the cam. After the "In-Target timeout" (Index 0x8020:0C) has elapsed, the calibration position (Index 0x8020:08) is taken on by the terminal as the current position.

Note

Observe the switching hysteresis of the cam switch

With this simple calibration it must be noted that the position detection of the cam is only exact to a certain degree. The digital inputs are not interrupt-controlled and are “only” polled. The internal propagation delays may therefore result in a system-related position difference.

For a more precise calibration, an HW sync pulse (C-track) is used in addition to the cam. This calibration proceeds in exactly the same way as described above, up to the point at which the motor travels away from the cam. The travel is not stopped immediately; instead, the sync pulse is awaited. Subsequently, the “In-Target timeout” runs down again and the calibration position is taken on by the terminal as the current position.

Calibration 2: — Calibration with cam and C-track

If calibration by hardware is not possible due to the circumstances of the application, the user can also set the “Calibrated” bit manually or automatically. The manual setting or deletion takes place with the commands “SET_CALIBRATION” and “CLEAR_CALIBRATION”.

It is simpler, however, if the standard start types (Index 0x8021:01) are set to “SET_CALIBRATION_AUTO”. The “Calibrated” bit will now be set automatically by the first rising edge on “Enable”. The command is conceived only for this purpose; therefore, it does not make sense to use it via the synchronous data exchange.