How To Select a Can Stack Linear Actuator

Digital Linear Actuator (DLA):
20 D A M 10 D 2 U -L

Motor Diameter
Denotes DLA
Step Angle
A = 15 deg
B = 7.5 deg
Rotor Size
M = Medium
L = Large
Linear Travel per Step
05 = .0005"
10 = .001"
20 = .002"
30 = .003"
40 = .004"
Magnet Type
B = Ferrite
D = Neodymium
1 = 5V
2 = 12V
Driver Type
U = Unipolar
B = Bipolar
Captive/Non-Captive Design
K = Captive
L = Non-Captive

Selection Criteria

Motor diameter

The motor diameter (sometimes referred to as frame size) is the diameter to the nearest mm of the motor casing. Matching the motor diameter to the available space in the application is typically the best place to start when sizing a DLA. In general, larger frame size motors deliver more force.

Step angle

A smaller step angle will provide more force but a slower speed, as well as greater positional accuracy.

Rotor size

This is a letter code that refers to the size of the rotor within the motor. While a larger rotor will provide more force, it will not always affect the size of the motor.

Linear travel per step

The distance the lead screw will travel with each step of the motor.

Magnet type

Stronger magnets will provide more force in the same size with the same current draw. Ferrite magnets are lower strength but lower cost, while more expensive Neodymium magnets are higher strength for high performance applications.

Rated voltage

Running the motor at rated voltage will yield catalog performance. A chopper drive can be used to alter the voltage and current to the motor to tailor to the specific application requirements.

Driver type

The type of motor chosen should match the type of driver used in the application (unipolar is 6 wires, bipolar is 4 wires).

Captive vs. non-captive

A captive design will provide purely translational motion of the shaft, ideal for applications where space is a constraint. A non-captive design will allow for longer stroke.