Digital Stepper Drive DM320T
7
driven motor (particularly at lower speed). Higher supply voltage will allow higher motor speed to be achieved, at the
price of more noise and heating. If the motion speed requirement is low, it’s better to use lower supply voltage to
decrease noise, heating and improve reliability.
6.1 Regulated or Unregulated Power Supply
Both regulated and unregulated power supplies can be used to supply the drive. However, unregulated power
supplies are preferred due to their ability to withstand current surge and fast response for current change. If you
prefer to a regulated power supply, it is suggested to choose such a power supply specially designed for stepper/servo
controls. Or, in the case when only normal switching power supplies are available, it is important to use “OVERSIZE”
high current output rating power supplies (for example, using a 4A power supply for 3A stepper motor) to avoid
problems such as current clamp. On the other hand, if unregulated supply is used, one may use a power supply of
lower current rating than that of motor (typically 50%
～
70% of motor current). The reason is that the drive draws
current from the power supply capacitor of the unregulated supply only during the ON duration of the PWM cycle,
but not during the OFF duration. Therefore, the average current withdrawn from power supply is considerably less
than motor current. For example, two 3A motors can be well supplied by one power supply of 4A rating.
6.2 Power Supply Sharing
Multiple DM320T drives can share one power supply to reduce cost, if that power supply has enough power capacity.
To avoid cross interference, connect each stepper drive directly to the shared power supply separately. To avoid cross
interference, DO NOT daisy-chain connect the power supply input pins of the Drivers. Instead connect them to power
supply separately.
6.3 Selecting Supply Voltage
The DM320T is designed to operate within 18-30VDC voltage input. When selecting a power supply, besides voltage
from the power supply power line voltage fluctuation and back EMF voltage generated during motor deceleration
needs also to be taken into account. Ideally it is suggested to use a power supply with the output voltage of 24VDC,
leaving room for power line voltage fluctuation and back-EMF.
Higher supply voltage can increase motor torque at higher speeds, thus helpful for avoiding losing steps. However,
higher voltage may cause bigger motor vibration at lower speed, and it may also cause over-voltage protection or
even drive damage. Therefore, it is suggested to choose only sufficiently high supply voltage for intended applications.
7. DIP Switch Configurations
This drive uses an 6-bit DIP switch to set microstep resolution, and motor operating current, as shown below:
7.1 Microstep Resolution Configurations
Microstep resolution is set by SW4, 5, 6 of the DIP switches as shown in the following table:
