Applied Motion 1240i User Manual

Page 8

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Mounting the Drive.

The 1240i has four 0.156 inch diameter holes in the circuit board for mounting.

Always use standoffs or spacers to support the 1240i: a 1240i with power connected

will be damaged if you set it on a conductive surface without supports. The standoffs

or spacers can be up to 0.25 inch in outer diameter. You can use #4 or #6 screws to

fasten the 1240i.

mounting holes

0.156 inch Diameter

mounting holes

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Microstepping

Most step motor drives offer a choice between full step and half step resolutions. In

full step mode, 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 1240i precisely control the amount of current in each

phase at each step position as a means of electronically subdividing the steps even

further. The 1240i offers a choice of 13 step resolutions. The highest setting divides

each full step into 254 microsteps, providing 50,800 steps per revolution when us-
ing a 1.8

motor.

In addition to providing precise positioning and smooth motion, microstep drives

can be used for motion conversion between different units. The 25,400 step/rev

setting is provided as a means of converting motion from metric to english (there are

25.4 mm in an inch). Other settings provide step angles that are decimal degrees
(36,000 steps/rev makes the motor take 0.01

steps). Some settings are used with

lead screws. When the drive is set to 2000 steps/rev and used with a 0.2 pitch lead

screw, you get 0.0001 inches/step.

The microstep resolution of the 1240i is set by the Si Programmer

software.