AMCI SMD34K, User Manual

Page: 16 / 100

SMD34K S
PECIFICATIONS
SMD34K User Manual
ADVANCED MICRO CONTROLS INC.
16
Available Discrete Inputs
The SMD34K has a total of three discrete DC inputs that accept 3.5 to 27Vdc signals. (5 to 24Vdc nominal)
How your SMD34K uses these inputs is fully programmable. The active state of each input is also program-
mable. Programming their active states allow them to act as Normally Open (NO) or Normally Closed (NC)
contacts. Two of these inputs are open collector sinking and share their common connection. The third input
is fully differential and can be wired as a sinking or sourcing input.
When using the Distributed Clock (DC) functionality of the EtherCAT system, Input 3 is not
available for use. Internally, the Input 3 circuitry is used by the SYNC0 signal to trigger a syn-
chronous command update. Input 3 must not be attached to sensors when using the DC func-
tionality.
Home Input
Many applications require that the machine be brought to a known position before normal operations can
begin. This is commonly called “homing” the machine or bringing the machine to its “home” position. An
SMD34K allows you to define this starting position in two ways. The first is with a Position Preset command.
The second is with a sensor mounted on the machine. When you define one of the inputs as the Home Input,
you can issue commands to the SMD34K that will cause the unit to seek this sensor. How the SMD34K actu-
ally finds the home sensor is described in the reference chapter
Homing an SMD34K starting on page 51.
CW Limit Switch or CCW Limit Switch
Each input can be defined as a CW or CCW Limit Switch. When used this way, the inputs are used to define
the limits of mechanical travel. For example, if you are moving in a clockwise direction and the CW Limit
Switch activates, all motion will immediately stop. At this point, you will only be able to jog in the counter-
clockwise direction.
Start Indexer Move Input
Indexer Moves are programmed through the Network Data like every other move. The only difference is that
Indexer Moves are not run until a Start Indexer Move Input makes a inactive-to-active state transition. This
allows an SMD34K to run critically timed moves that cannot be reliably started from the network due to data
transfer lags.
If the unit was ordered with the encoder option, and one of the discrete DC inputs is programmed as a Start
Indexer Move Input, then the encoder position data will be captured whenever the DC input makes a transi-
tion. An inactive-to-active state transition on the DC input will also trigger an Indexer Move if one is pending.
Emergency Stop Input
When an input is defined as an Emergency Stop, or E-Stop Input, motion will immediately stop when this
input becomes active. The driver remains enabled and power is supplied to the motor. Any type of move,
including a Jog or Registration Move, cannot begin while this input is active.
If a move is in progress when this input becomes active, the SMD34K responds by shorting the
motor’s windings together. This forces any regeneration energy to be dissipated in the windings
instead of being reflected back into the power supply. The windings will be shorted for up to
300 milliseconds. Once the short is removed, the SMD34K will set a bit in the network input
data to show that motion is stopped and the unit is ready to accept your next command.