CANopen DSP 402 Implementation Guide
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Various homing positions are illustrated in the diagrams that follow (section 9.4). A circled number indicates the code for selecting the homing position. The direction of movement is also indicated.
Additional homing methods are available with other modes of the Elmo drives, such as the binary interpreter or the user program.
Four sources of homing signal are available: the negative and positive limit switches, the home switch and, and the index pulse, which are handled by fast inputs. The captured value is independent of drive sampling time. Limit switches must be previously defined during the drive setup (using the IL[N] command).
In the homing sequence diagrams, the encoder count increases as the axle position moves to the right. In other words, the left is the minimum position and the right is the maximum position. In the SimplIQ drive, the user may select the configuration; otherwise, it is determined according to the setup process.
Error Cases
Error cases are events in which the drive cannot reach the home method or operate the home demand parameters, such as high speed. In cases where the limit is known in advance — such as home speed higher than the speed limit — an abort message is executed. In cases where a fault is hit during the operation of the home procedure — such as an abort switch — the drive goes into a fault state. The homing error bit in the statusword is set and an emergency message for motor fault, if not masked, is transmitted. The error register can be monitored for the fault indication. In cases where a limit prevents the home sequence from being finished, such as reaching a mechanical limit, no special indication is given. It is up to the application to monitor or set a timeout sequence for the home procedure.
