Glentek Inc. 208 Standard Street, El Segundo, California 90245, U.S.A. (310) 322-3026
7
Selecting a Glentek Servo Motor to Replace a Stepper Motor
This section provides the specifications of various stepper motors so they can be compared to
equivalent servo motors. This should help in clearing up some of the confusion involved in choosing a
servo motor to replace a stepper.
Both Servo and Stepper motors have peak and continuous torque ratings. You will notice that the
peak and continuous torque ratings are generally the same with the stepper motor. Whereas, in a
servo motor, the peak torque rating is generally two or three times higher than the continuous torque
rating.
To select a servo motor, the peak torque must be equal to or greater than the peak torque rating of
the step motor. Since the horse power to weight ratio of a stepper motor is similar to that of a servo
motor, you should start out by selecting a servo motor approximately the same weight as the stepper
motor.
As a final system test, after selecting the Glentek servo motor replacement for your stepper motor,
Glentek strongly recommends you to install the servo motor and exercise your machine at maximum
axis duty cycle to make sure that the servo motor runs without over heating and the following error re-
mains within desired specification.
in-lb = in-oz x 0.0625 N-m = in-oz x 0.007
Frame
Size
Stepper Motor
Glentek Servo Motor
Torque
(in-oz)
Weight
(lbs)
Model
Number
Peak Torque
(in-oz)
Cont. Torque
(in-oz)
Weight
(lbs)
Overall
Length (inches)
NEMA 23
185
1.5
GMBN2310
216
72
@2.7 Amps
2.3
4.59
NEMA 23
495
3.1
GMBN2320
588
168
@4.7 Amps
3.8
6.12
NEMA 34
247
3.2
GMBN3405
297
99
@1.8 Amps
4.2
4.20
NEMA 34
465
3.7
GMBN3410
595
198
@3.4 Amps
5.7
5.26
GMBN3420
850
298
@7.5 Amps
9.0
6.89
NEMA 34
640
5.3
NEMA 34
1160
8.8
GMBN3430
1188
396
@6.0 Amps
12.0
7.88
NEMA 42
1869
16.53
GMBN4230
1274
424
@7.9 Amps
15.0
6.42
NEMA 42
2830
19.8
GMBN4260
2547
848
@15.8 Amps
21.0
8.78
