Applied Motion 3540MO - Manual (Page 7)

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Microstepping
Most step motor drives offer a choice between full step and half step resolutions. In
most full step drives, both motor phases are used all the time. Half stepping divides
each step into two smaller steps by alternating between both phases on and one
phase on. Microstepping drives like the 3540 MO precisely control the amount of
current in each phase at each step position as a means of electronically subdividing
the steps even further.
The 3540 MO divides each full step into 64 microsteps, providing 12,800 steps per
revolution for precise positioning and smooth motion.
5k Ω
joystick
joystick "fire" button
fwd
rev
3540 MO
COM
DIR (REV LIMIT)
RUN (FWD LIMIT)
SPD
CCW
WPR
CW
+
5-24
VDC
SUPPLY
-
rev limit switch
fwd limit switch
Typical wiring for Joystick Mode
0 1 2 3 4 5
-25
-20
-15
-10
-5
0
5
10
15
20
25
Speed vs Input Voltage
Joystick mode, SPD input off (or open)
HI SPEED pot at maximum
volts volts
speed (rev/sec)
0.1
0.2
0.4
0.8
1.6
45678
Setting Phase Current
Before you turn on the power supply the first time, you need to set the driver for the
proper motor phase current. The rated current is usually printed on the motor label.
The 3540 MO drive current is easy to set. If you wish, you can learn a simple
formula for setting current and never need the manual again. Or you can skip to the
table on the next page, find the current setting you want, and set the DIP switches
according to the picture.
Current Setting Formula
Locate the bank of tiny switches near the motor connector. Four of the switches
have a value of current printed next to them, such as 0.4 and 0.8. Each switch
controls the amount of current, in amperes (A), that its label indicates. There is
always a base of current of 0.4 A. To add to that, slide the appropriate switches
toward their labels on the PC board. You may need your small screwdriver for this.
Example
Suppose you want to set the driver for 2.2 amps per
phase. You need the 0.4 A base current plus another 1.6
and 0.2 A.
2.2 = 0.4 + 1.6 + 0.2
Slide the 1.6 and 0.2 A switches toward the labels as
shown in the figure.