DM870 Digital Stepping Driver Manual V1.0
Tel: +086 0755-26434369 9 Web Site: www.leadshine.com
7. Selecting Microstep Resolution and Drive Output Current
Microstep resolutions and output current are programmable, the former can be set from full-step to
102,400 steps/rev and the latter can be set from 0.5A to 7.0A. See more information about
Microstep
and Output Current Setting
in Section 13.
However, when it
’
s not in software configured mode, this Drive uses an 8-bit DIP switch to set
microstep resolution, and motor operating current, as shown below:
Microstep Resolution Selection
When it
’
s not in software configured mode, microstep resolution is set by SW5, 6, 7, 8 of the DIP
switch
as shown in the following table:
Microstep
Steps/rev.(for 1.8
°
motor)
SW5
SW6
SW7
SW8
1 to 512
Default/Software configured
ON
ON
ON
ON
2
400
OFF
ON
ON
ON
4
800
ON
OFF
ON
ON
8
1600
OFF
OFF
ON
ON
16
3200
ON
ON
OFF
ON
32
6400
OFF
ON
OFF
ON
64
12800
ON
OFF
OFF
ON
128
25600
OFF
OFF
OFF
ON
5
1000
ON
ON
ON
OFF
10
2000
OFF
ON
ON
OFF
20
4000
ON
OFF
ON
OFF
25
5000
OFF
OFF
ON
OFF
40
8000
ON
ON
OFF
OFF
50
10000
OFF
ON
OFF
OFF
DM870 Digital Stepping Driver Manual V1.0
Tel: +086 0755-26434369 10 Web Site: www.leadshine.com
100
20000
ON
OFF
OFF
OFF
125
25000
OFF
OFF
OFF
OFF
Current Settings
For a given motor, higher Drive current will make the motor to output more torque, but at the same
time causes more heating in the motor and Drive. Therefore, output current is generally set to be such
that the motor will not overheat for long time operation. Since parallel and serial connections of
motor coils will significantly change resulting inductance and resistance, it is therefore important to
set Drive output current depending on motor phase current, motor leads and connection methods.
Phase current rating supplied by motor manufacturer is important in selecting Drive current, however
the selection also depends on leads and connections.
When it
’
s not in software configured mode, the first three bits (SW1, 2, 3) of the DIP switch are used
to set the dynamic current. Select a setting closest to your motor
’
s required current.
Dynamic current setting
Peak Current
RMS Current
SW1
SW2
SW3
Default/Software configured (0.5 to 7.0A)
OFF
OFF
OFF
2.6A
1.8A
ON
OFF
OFF
3.4A
2.4A
OFF
ON
OFF
4.0A
2.8A
ON
ON
OFF
4.8A
3.4A
OFF
OFF
ON
5.4A
3.8A
ON
OFF
ON
6.1A
4.3A
OFF
ON
ON
7.0A
5.0A
ON
ON
ON
Notes:
Due to motor inductance, the actual current in the coil may be smaller than the dynamic
current setting, particularly under high speed condition.
Standstill current setting
SW4 is used for this purpose. OFF meaning that the standstill current is set to be half of the selected
dynamic current, and ON meaning that standstill current is set to be the same as the selected dynamic
current.