AMCI SMD17K, Руководство пользователя

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20 Gear Drive, Plymouth Ind. Park, Terryville, CT 06786
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Tel: (860) 585-1254 Fax: (860) 584-1973 http://www.amci.com
SMD17K User Manual
SMD17K S
PECIFICATIONS
15
Driver Functionality
This table summarizes the features of the stepper motor driver portion of an SMD17K.
Table R1.2 Driver Functionality
Idle Current Reduction
Idle Current Reduction allows you to prolong the life of your motor by reducing its idling temperature. Values
for this parameter range from 0% (no holding torque when idle) to 100%.
Idle current reduction should be used whenever possible. By reducing the current, you are reducing the I
2
R
losses in the motor, which results in an exponential, not linear, drop in motor temperature. This means that
even a small reduction in the idle current can have a significant effect on the temperature of the motor.
Note that the reduction values are “to” values, not “by” values. Setting a motor current to
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2 Arms and the current reduction to 25% will result in an idle current of 0.5 Apk. (The
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SMD17E always switches from RMS to peak current control when the motor is idle to
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prevent motor damage due to excessive heating.)
Available Discrete Inputs
The SMD17K has two discrete, sinking, DC inputs that accept 3.5 to 27 Vdc signals. (5 to 24 Vdc nominal)
How your SMD17K 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.
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
SMD17K 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 SMD17K that will cause the unit to seek this sensor. How the SMD17K actu-
ally finds the Home sensor is described in the
Homing an SMD17K chapter starting on page 49.
Feature Benefits
RMS Current Control
RMS current control give an SMD17K the ability to drive the motor at its
fully rated power regardless of the programmed steps per turn. There is no
reduction in power when microstepping that may occur with other drivers.
Programmable
Motor Current
RMS current supplied to the motor can be programmed from 0.1 to 2.0
amps in 0.1 amp increments. Reducing the motor current to the minimum
needed for your application will significantly reduce the motors operating
temperature
Programmable Idle
Current Reduction
Extends motor life by reducing the motor current when motion is not
occurring. This extends the life of the motor by reducing its operating
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temperature.
Programmable
Motor Steps/Turn
Allows you to scale your motor count to a real world value. (counts per
inch, counts per degree, etc.)
Anti-Resonance Circuitry
This feedback circuitry and algorithm gives the SMD17K the ability to
modify motor current waveforms to compensate for mechanical resonance
in your system. This will give you smooth performance over the entire
speed range of the motor.
Over Temperature
Detection
An SMD17K sets a warning bit in the network data when the temperature
of the unit approaches its safe operating threshold.
Over Temperature
Protection
Protects your SMD17K from damage by removing power from the motor if
the internal temperature of the driver exceeds the safe operating threshold
of 203°F/95°C.