Motor bases work as mounts for electric motors. The devices are installed with adjustable bolt patterns suitable for different-sized motors that enable necessary position adjustments to the motor. Most bases fit NEMA electric motor sizes.

The base regulates the pressure in a belt-driven system. That is critical for staying away from belt slippage and excessive strain that lead to higher maintenance costs and extra downtime. Optimal belt tension helps lengthen the support lifetime of components, such as belts and motor bearings.


Today’s marketplace features multiple types of electric motor bases with two principal categories, including:

Fixed-placement adjustable bases: These adjust via manual alteration of the center range that separates a driver and driven pulleys. They enable pushing or pulling a engine into spot to install or adapt the belt. After the belt is stopped the pulley, one or multiple screws pressure the motor from the driven pulley until the desired tension level is certainly attained. The installation bolts are then tightened to comprehensive the process.

Base style ranges from simple, one-piece, formed plates to more complex models featuring Z-pubs with continuous welding to improve strength. Select versions match NEMA mounting sizes. Fixed-position bases are preferred due to low initial costs.

The equipment is further divided into the following classifications:

Single-screw adjustable bottom possesses a central screw for tension positioning. As the screw turns, the engine movements with the pulley center towards or from the guts of the powered pulley. The operational simplicity offered by this device offers a reasonably-priced option for a number of applications.

Dual-screw positioning base has two adjustable screws placed beneath the motor ft. Its configuration matches single-screw systems but with reinforced building for extending the application form range. In comparison with the single-screw style, this type of setup supports higher versatility in shaft alignment and dual screws give a robust method of maintaining alignment.

Specialized fixed-position bases feature mounting studs extending from slots. While performing tension modifications the nuts are loosened and the electric motor is definitely lifted above the studs. If the nuts are loosened more than was necessary, the motor will turn and shift nearer to the driven pulley through the Stainless Steel Chain tightening process. Because of this the tension will exceed the required level and the installation studs will encounter excessive strain when tightening the nuts.

Tension-controlling bases: The structures integrate external or internal tools that automatically alter the center distance of a pulley of a working engine in response to load condition requirements.

Types of tension-controlling gadgets comprise:

Pivot bases depend on a motor’s weight along with its direction of rotation for applying and controlling stress. The motor is mounted on pivoting arms and is held set up with bolt holes and slots configured to fit the frame. The strain in the belt increases with the length of the electric motor from the pivoting shaft. Once started, the motor’s response torque extends the pulley’s center range and builds tension by directing the pivoted arm downward. The hands move upward to decrease the center range as the operating load increases.

Spring-loading bases employ built-in springs to control belt strain. This unit features a motor added to cross members connected to tubes. The formed carriage shifts towards or from a driven member in response to fluctuating load. The engine can be bolted to the free-shifting carriage. When the adjustment screw is certainly turned clockwise, the follower nut, spring, and carriage move around in the direction reverse to the powered pulley. After installing the belt, additional rotation of the screw pushes the carriage to a point where in fact the belt is snug.

Conversion engine bases match newer, smaller motors after they have undergone rerating to support older mounts.

Heavy duty and custom-built bases serve particular purposes and applications. Heavy-duty versions comprise reinforced construction and heavier materials to handle additional stress. Unique gussets along with cross braces are sometimes found in these units.


Fixed-position mechanisms are selected because of their cost advantage over more costly tension-controlling equipment. They are available in styles that are standard to NEMA mounting dimensions and provide sufficient belt tension control. However, such configurations have specific drawbacks, including:

With out a movable plate for mounting, system alignment is performed when it is not really operating. This entails a particular amount of guesswork and is definitely less optimal than producing changes in dynamic mode.
When the engine is secured in position and the belt aligned, pulley middle distance is locked in. If belt tension is not adequate to operate a vehicle a maximum load with no slippage, stress can lead to extra wear of elements.
Such structures face difficulty in dealing with load fluctuations and shock or vibrations.
Tension-controlling bases are more efficient to set up and operate. They cope better with situations including variation in weight. These units hold the benefit in scenarios where many alterations are required due to area and environment, or where unique mounting requirements can be found. They decrease the time to execute changes and can mount motors vertically or horizontally.
If you want to know more about the motor base, please contact us for more information.