Motor Comparison

Dozens of motors are compared here based on specifications such as test voltage, unloaded speed, stall torque, and cost. The Tetrix DC Motor - new model W739530 operates at a test voltage of 13.96 volts, achieving an unloaded speed of 167 revolutions per minute (rot/min) and a stall torque of 1,100 oz-in. Its peak power is estimated to be between 10 to 18 watts, with a speed at peak power ranging from 7 to 13 rot/min and a torque at peak power of 75 oz-in, making it suitable for continuous use at a cost of $17.47. The older version, the Tetrix DC Motor - old model W739083, also runs at 13.96 volts but has a slightly higher unloaded speed of 176 rot/min and a lower stall torque of 400 oz-in, with a peak power of 10.70 watts.

In contrast, the AndyMark NeveRest 40 (model am-2964) shares the same test voltage of 13.96 volts and matches the unloaded speed of 176 rot/min, but it has a higher stall torque of 750 oz-in and estimated peak power of around 14 watts. This motor is priced at $25, which includes an encoder. The HS-785HB (QS) servo operates at a lower test voltage of 6.00 volts, with an unloaded speed of 43.48 rot/min and a stall torque of 183.31 oz-in, offering a peak power of 1.47 watts and a continuous travel capability, priced at $59.95.

Another servo, the HS-755HB (QS), also runs at 6.00 volts with the same unloaded speed of 43.48 rot/min and stall torque of 183.31 oz-in, but it is more affordable at $34.95. The HS-485HB, operating at the same voltage, has an unloaded speed of 55.56 rot/min and a lower stall torque of 83.30 oz-in, with a peak power of 0.85 watts, costing $17.47. The HSR-1425CR, equivalent to the Tetrix CR W39177, operates at 6.00 volts with an unloaded speed of 52.00 rot/min and stall torque of 42.00 oz-in, providing a peak power of 0.40 watts and priced at $18.87.

The NXT Motor (model 9842) shows versatility with two voltage ratings; at 9.00 volts, it achieves an unloaded speed of 170 rot/min and a stall torque of 49.56 oz-in, with a peak power of 2.04 watts, while at 7.00 volts, it has a lower unloaded speed of 135 rot/min and stall torque of 38.23 oz-in, with a peak power of 1.43 watts, both costing $19.99.

The data also includes a torque comparison chart that illustrates the performance of various motors at different torque levels. For instance, at zero torque, the AndyMark NeveRest 40 reaches a maximum speed of 176 rot/min, while the Tetrix DC Motor - new model W739530 follows closely at 167 rot/min. As torque increases to 10 oz-in, the speeds of these motors decrease slightly, with the NeveRest 40 at 173.65 rot/min and the new Tetrix at 165.48 rot/min.

At higher torque levels, the performance continues to vary; for example, at 100 oz-in, the AndyMark NeveRest 40 motor maintains a speed of 152.53 rot/min, while the Tetrix DC Motor - old model W739083 drops to 132.00 rot/min. The HS-785HB servo, at the same torque level, does not provide any speed, indicating its limitations under higher loads.

The chart continues to show that as torque increases, the unloaded speeds of the motors decline significantly, with the NeveRest 40 motor demonstrating a more gradual decrease compared to the others. The data highlights the performance characteristics of each motor, emphasizing their suitability for different applications based on their torque and speed capabilities.