Advanced Micro Controls Inc. SMD17E2 - Homing Inputs; Physical Inputs; Network Data Input; Homing Configurations

HOMING AN SMD17E2 SMD17E2 User Manual
ADVANCED MICRO CONTROLS INC.
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Homing Inputs
Both of the physical DC inputs can be used when homing the driver. A Backplane Proximity bit is available in
the network output data that can be used to control when the home input is acted upon. This is typically used
in applications where the home input is triggered multiple times in a machine cycle, and the system need to
control which trigger is acted upon.
Physical Inputs
 Home Input: This input is used to define the actual home position of the machine.
 CW Limit Switch Input: This input is used to prevent overtravel in the clockwise direction.
 CCW Limit Switch Input: This input is used to prevent overtravel in the counter-clockwise direction.
Network Data Input
 Backplane_Proximity_Bit: An SMD17E2 can be configured to ignore changes on the physical hom-
ing input until the Backplane_Proximity_Bit makes a 01 transition. The unit will home on the next
inactive-to-active change on the physical input once this transition occurs. You must program your host
to control the state of this bit.
This bit is disabled by default, and must be activated when you configure the SMD17E2
before is can be used. If you decide to activate this bit when you configure the unit and then
never set it to a “1”, the SMD17E2 will never act on the physical Home Input.
Homing Configurations
A SMD17E2 must have one of its DC inputs configured as the home input before one of the CW/CCW Find
Home commands can be issued.
1) You do not have to configure and use CW or CCW Limits. If you choose to configure the
unit this way, then the SMD17E2 has no way to automatically prevent over travel during a
homing operation. In linear applications, you must prevent over travel by some external
means, or ensure that the homing command is issued in the direction that will result in
reaching the homing input directly.
2) You can use a bit in the Network Output Data (the Backplane_Proximity_Bit) as a home
proximity input. Using this bit is completely optional and prevents the Home Input from
being acted upon until the Backplane_Proximity_Bit makes a 0
1 transition.