More on Treadmill Motors
To buy the right treadmill, you really don’t need to know more than what’s discussed in Treadmill Motors. However, if you really want to know more, here it is!
As explained in the above article, “continuous duty” horsepower is the best expression of a motor’s strength. But another consideration is at what speed the motor has to turn to produce that power. That is, at what RPM (revolutions per minute)? The slower a motor has to turn to produce a given amount of belt-turning power, the less stress on the motor and the longer it will last. This motor turning and belt turning power is also known as torque.
A practical application of all this in shopping for a treadmill is to make sure the motor has enough horsepower for the speed (RPMs) that it is likely to be used. It is unlikely that you will be going so fast on the treadmill that the motor should turn at more than 5,000 RPM. A complete (and rarely provided) horsepower rating would give both the continuous horsepower and the RPM rating, such as 3.0 chp @3,000 rpm. If the horsepower rating for a motor is for greater than 5,000 RPM, it will likely heat up too quickly, and maybe overheat, unless is has a very high horsepower.
Of course, treadmill manufactures know all this and usually match the motor’s horsepower and RPMs with the likely use of the machine. If the motor is in a runner’s treadmill and spins at fewer than 4,000 RPMs, or a walker’s that at fewer than 5,000 RPMs, the motor should run cool, smooth, and quiet, and last a lifetime.
The optimal match of a motor’s horsepower and RPMs with the treadmill’s use will also result in the treadmill using less electricity. Which brings us to another motor measurement. How much electricity does the motor use when it producing that horsepower?
The amount of electrical current used by a treadmill motor is partially explained by the voltage, or amount of electrical power, necessary to run the motor. Thus, for example, a motor may be 2.0 chp, rated at 100 volts. That means the motor requires 100 volts of electricity to produce that level of horsepower. The voltage that is transmitted is controlled by the treadmill’s controller, so the voltage rating of the motor needs to be at most within the voltage allowed by the controller.
AC v. DC
If you’re still reading this, you’ll probably want one last electrical fact about treadmill motors. Is the motor AC or DC?
Residences in the United States are equipped with AC (alternating current). Gym treadmills typically have AC motors. AC motors are usually more powerful than DC (direct current) motors. So shouldn’t your treadmill also have an AC motor?
Actually, no. Home treadmills, like other home appliances, have DC (direct current) motors. All these appliances convert the home’s AC current to DC so it can run the DC motor. DC motors are used in treadmills because they are quieter than AC motors and provide more consistent output, especially at higher RPMs. They also get to top speed more quickly than AC motors. Thus, it is very unusual to find a home treadmill with an AC motor.