DM860 Fully Digital Stepper Drive Manual V1.0
7
Since parallel and serial connections of motor coils will significantly change resulting inductance and resistance, it is
therefore important to set driver output current depending on motor phase current, motor leads and connection methods.
Phase current rating supplied by motor manufacturer is important in selecting driver current, however the selection also
depends on leads and connections.
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
REF Current
Peak Current
SW1
SW2
SW3
2.00A
2.40A
ON
ON
ON
2.57A
3.08A
OFF
ON
ON
3.14A
3.77A
ON
OFF
ON
3.71A
4.45A
OFF
OFF
ON
4.28A
5.14A
ON
ON
OFF
4.86A
5.83A
OFF
ON
OFF
5.43A
6.52A
ON
OFF
OFF
6.00A
7.20A
OFF
OFF
OFF
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.
The current automatically reduced to 50% of the selected dynamic current one second after the last pulse. Theoretically,
this will reduce motor heating to 36% (due to P=I
2
*R) of the original value. If the application needs a different
standstill current.
28B
