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Help Page -How to Choose the Best Rotator for Your Project.

If you are unfamiliar with sign rotators this page will help you determine the best rotator for your project. To begin with, there are two types of rotators, indoor and outdoor. We make two types of indoor rotators, compact and the larger standard size. Click here for information on compact rotators.

Standard size rotators look similar and have the same components but outdoor rotators require more powerful drive systems to meet weather conditions. The illustration below shows the main components of our rotators. Indoor rotators typically turn at about 2 revolutions per minute, outdoor rotators normally turn faster at 4 to 6 revolutions per minute.

Semco rotator diagram

Indoor rotators come in many different sizes based mostly on the weight of the sign or display to be rotated. Larger rotators usually have more powerful drive systems since more weight requires more turning torque. If your display will be evenly balanced and will rest on the hub plate of the rotator you can match the rotator that is rated for the sign weight. For example, if you have a display weighing 250 lbs that is evenly balanced we would recommend our T100-5C compact rotator rated for 300 lbs. If you have the same display that will be mounted vertically on a wall, we would recommend a larger T100-5X compact rotator with a more powerful drive system.

 If you have a tall display or an eccentric or unbalanced display, you should consider using a rotator that is rated above the weight of your display. Also keep in mind that an unbalanced load will put more stress on the bearings resulting in a shorter overall bearing life. Using a rotator with a higher load rating may prolong the life of the bearings.
Collector and brushes: the number of circuits you require will determine how many collector rings you will need. "F" Model rotators and compact rotators mounted upside down require an additional circuit to power the rotator. With this type of application, your electric wires must pass through the collector to the brushes. The motor is powered by the brushes; the rotator frame turns with the display or sign. Consult an electrician if you are unsure of the power requirements of your lighting system. Our rotators come equipped with 115V motors, and turn in the clockwise direction at 2 to 3 rpm. As an option, motor voltage, rotation direction, and speed can be changed on most models. We also have variable speed motors for most of our revolving units.

Mounting: Most of the time the rotator is located out of the site of the viewer. The rotator can be positioned under the display in a cabinet, inside the display, or above. Our rotators have drilling in the hub plate, base plate, and the side of the frames and on our compact models we include tapped holes on the sides of the rotator frames. Your sign or display should be engineered to support the total weight of the display as well as side loading, electrical requirements and public safety. If you want to hang the rotator and display, please let us know when you order so we can add safety features for this type of application. Our accessory companion matching plates make it easy to mount your display to the hub of the rotator, simply weld the plate to the post that supports the display, then bolt the companion plate to the rotator hub.

Outdoor Rotators: Your sign becomes a sail when the wind hits it. Even a relatively light weight sign can generate an enormous amount of side force or bending moment when hit by wind. Depending on the wind conditions of the area the sign will be installed, the same sign could require different size rotators. A rotator mounted high inside the sign will see less force than a rotator mounted below the sign and can therefore be smaller, however, this type of installation is not always feasible. We offer accessories such as split plates and stub bearings to support the sign opposite the rotator. You should always consult an engineer when considering outdoor sign installations. Please see the installation links below to determine the recommended rotator for your project. If the sign will be used in a high wind area, please call for free consultation on rotation selection.


Please call if you have any questions determining the size rotator required for your project.

Outdoor Illustrations

"F" Model rotators mount inside sign near the top - known as Figure 1 installations

"F" Model rotators mounted inside sign near bottom of sign - Figure 1A installations

"T" Model installations - Rotators that mount under the signs