AMCI SD17060E-K, Руководство пользователя

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Networked Indexer/Driver User Manual
SD17060E-K & SD31045E-K S
PECIFICATIONS
13
Indexer Functionality (continued)
Synchronizing Moves
By default, the Networked Driver products use the SyncManager 2 event to control the transfer of data from
the EtherCAT Slave Controller (ECS) to the microprocessor that controls motion. This allows the Networked
Driver to execute commands as soon as new data arrives. When more than one axis is updated with a single
EtherCAT packet, the time difference between axis updates is very short. Updating multiple axes with a single
packet allows the EtherCAT network to out perform the update times of other industrial network protocols.
On very fast machines, or large machines that require more than one transfer to update all axes, the EtherCAT
Distributed Clock (DC) functionality can be used to closely synchronize motion over multiple axes if using
the SyncMaster2 event proves to be ineffective.
The EtherCAT Distributed Clock functionality is built into the ECS used by the Networked Driver products.
The Networked Driver can act as the reference clock for the system if it is the first device in the EtherCAT
network. The SYNC0 signal, which is based off of the Distributed Clock, can be use to synchronize the start
of moves over multiple devices. The time between when the SYNC0 signal is received by the main processor
of the Networked Driver and when the driver begins to cause motion is 520 ± 25 microseconds. The 520
microseconds is the time required to read the data from the ECS once the SYNC0 signal becomes active. The
±25 microseconds is caused by the 20 kHz update frequency of the PWM drivers.
For the Networked Driver, the minimum update time on the SYNC0 signal is two milliseconds. If the task
time is less than two milliseconds, the SYNC0 time must be a multiple of the task time.
Encoder Functionality
Two of the three inputs available on the Networked Drive can be configured to accept AB quadrature signals
from an incremental encoder. These signals are always decoded using X4 decoding. When configured this way,
the indexer section of the Networked Driver has the following additional functionality.
Table R1.2 Indexer Encoder Functionality
Stall Detection
When Stall Detection is enabled, the Networked Driver monitors the encoder for position changes, regardless
of whether or not a move is in progress. If the error between the encoder position and the motor position
exceeds forty-five degrees, the Networked Driver responds in the following manner:

The stall is reported in the network input data.

The motor position becomes invalid. (The machine must be homed or the motor position preset before
Absolute moves can be run again.

If a move was in progress, the move is stopped.
Note that a move does not have to be in progress for stall detection to be useful. By enabling stall detection,
the Networked Driver can notify the system if the motor shaft moves more than forty-five degrees while the
motor should be holding the load. For example, if the motor should hold a load against gravity, but the Idle
Current Reduction parameter is set to high, the Networked Driver will issue a stall detection error if the load
begins to fall.
Feature Description
Stall Detection
When the Networked Driver is configured to accept an encoder, the encoder
can be used to verify motion when a move command is issued.
Encoder Registration
Move
Uses the count from a quadrature encoder to determine when a move begins
to decelerate and stop. Commonly used in spooling/despooling applications.
Electronic Gearing
The Networked Driver can be configured to control the position of a motor
based on feedback from an external encoder. The ratio of encoder pulses to
motor pulses is full programmable and can be changed on-the-fly.