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Reference drive
The SMS14 detects the position of the step motor via a reference drive. The step motor will be closed
or opened completely, and the SMS14 gains its orientation via the reference drive.
If Jumper J4 is set, the SMS14 opens the step motor completely, and defines the position “0%” as
the step motor being completely open.
If Jumper J4 is not set, the SMS14 closes the step motor completely, and defines the position “0%”
as the step motor being completely closed.
The reference drive is carried out once as the device boots (= when power is supplied).
Holding current
If Jumper J3 is not set, the SMS14 outputs 30% of current to the step motor as soon as its target
position is reached in order to hold that position.
If Jumper J3 is set, no holding current will be output.
Power supply
The module requires a 12V power supply. Terminals for supply are situated on the left side of the
PCB.
PWM control
The SMS14 has a PWM input. This allows for setting the target position of the connected step motor.
Signals with a frequency between 500Hz and 3kHz can be read. 1kHz is recommended.
The PWM signal is interpreted linearly from 5% to 95%.
• <5% PWM: 0% of max. motor position
• 5%-95% PWM: sets target position linearly from 0-100% of max. motor position
• >95% PWM: 100% of max. motor position
+12V
GND
PWM
GND
