Special functions: reset, latch, set position

Latch and/or Reset can be activated on the C-signal in the CoE. It is not recommended to activate both functions at the same time.

Reset

The internal counter is reset immediately to 0 when the C-signal reaches the EL5021.

Latch

When the C-signal reaches the EL5021, a new position determination is started and the last determined position is “latched” (stored); see fig. "Latching" of a position, Signal C_A. The latch determination is handled with priority if the latch signal falls in terms of time within the range of the triggered position determination; the regular position determination is then executed immediately afterwards, see signal C_B.

This delay has no meaning in the synchronous operating mode; in DC mode sufficient time reserves are available so that GetPos can nevertheless be executed in time for the next EtherCAT cycle, ensuring that current data can be delivered.

Fig.144: “Latching” of a position

Set position (set counter)

The position value specified in 0x7000:11 (counter value) is reset via the index 0x7000:03.

Set position The use of the “Set position” function is recommended only when the axis is at a standstill.