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MOONS’
MSSTAC6 Step Motor Drive User Manual
MOONS’
www.moons.com.cn
of voltages in which the motor does not run and is useful for stopping the motor when the joystick is
released.
Direction
The X2 input is used to select the direction of rotation. If the motor is moving when the state of the
direction input is changed, the motor will decelerate to stop then accelerate to the same speed in the
opposite direction.
Filter Frequency
If the analog signal is noisy, the motor speed may not remain constant. Industrial systems often pick up
electrical noise on an analog wire and the STAC6's high resolution 12-bit analog input may respond to the
noise. If this occurs, the analog filter frequency should be lowered until the issue is resolved. If the frequency
is set too low, the motor may change speed more slowly than specified in the acceleration and deceleration
boxes due to excessive filtering.
Motion Output
Output Y2 can be used to tell another piece of electronics what the drive is doing in velocity mode. If a
signal will indicate when a motor is in motion, there are two choices: Y2 can be closed when the motor is
moving and open when it is stopped, or Y2 can be open when moving and closed when stopped. If a
tachometer output is being used (a signal proportional to the motor speed), Y2 can emit pulses as the motor
turns, (100 square wave pulses per revolution for a 1.8° motor, otherwise 2 times the motor electrical
frequency).
Additional settings or 200, 400, 800 and 1600 pulses/rev are available for drives with DSP firmware
version 1.02 or later. However, the signal may not be accurate at higher speeds. Please examine the table
below for details.
tach ppr
accurate at
speeds
100
0 - 50 rev/sec
200
0 - 25
400
0 - 12.5
800
0 - 6.25
1600
0 - 3.125
Note: Signal integrity is best with an 80 mA load (use 300 ohms at 24V, 150 ohms at 12V or 62 ohms
at 5V.)
SCL Mode
Here the power up mode for the drive is set for use with SCL applications.
SCL is MOONS' host command language for applications requiring drives to receive instructions from a
host controller in real time. With SCL, drives can be operated in both RS-232 and RS-485 mode. The RS-485
option allows for multi-axis, multi-drop applications with drives "daisy chained" on one serial link. When this
option is selected the address of each drive will need to be set.
