An AC drive is an essential component for controlling the speed and efficiency of an electric motor. Growing demand worldwide for energy-efficient process flows means that AC drives are more important than ever to the future of process controls.Here we’ll discuss the features, benefits, and applications of AC drives in more detail.
What Is an AC Drive?
AnAC driveis a device utilized to control the speed of an electric motor. It is also known as a variable frequency drive, variable speed drive, and adjustable speed drive.
The AC drivecontrols the speed by changing the frequency of the electrical supply to the corresponding motor. Motor speed changes proportionally to the frequency. AC drives accomplish the following objectives:
Improve process control
Minimize mechanical stress on motor control systems
Optimize the overall operation of the application
AC Drive Benefits
Here are the advantages of an AC drive:
Energy efficiency. AC drives minimize peak energy demands by drawing more power from the motor. In many applications, AC drives can save as much as 50% in energy expenses.
Versatility. An AC drive controls more than just motor speed. Additional features include multi-use programmability and self-diagnostics. AC drives can also operate in hazardous environments like petrochemical plants, where DC drives are unsuitable.
Power factor. With light loading, motors tend to have poor power factors. AC drives increase the power factor in these applications and remove the need for utility power factor charges or correction capacitors.
Reduced stress. AC drives precisely control starting and stopping, which reduces mechanical wear throughout the system.
Compact size. An AC drive is smaller and lighter than other motor control methods.
AC drives are widely used in applications across many industries. Common uses for AC drives include:
TECO Westinghouse is a top-quality supplier of AC and DC motors and generators. For over 100 years, TECO Westinghouse has been a leader in motor design and application. Gainesville Industrial Electric is a certified distributor of TECO Westinghouse products, which include a comprehensive line of both low voltage and medium voltage AC drives. We carry top brands like Mitsubishi and Worldwide Electric to ensure our customers have robust, reliable drives for their critical applications.
Contact Our Experts for Your AC Drive Needs
AC drives are the most reliable and energy-efficient method to control electric motor speeds. For high-quality AC drives to control the speed of your motors, consult with the experts at Gainesville Industrial Electric. Our team can help you select the best option for your application. We provide same-day shipping for all products in stock.
An industrial gearbox is a type of enclosed system responsible for transmitting mechanical energy to designated units. In the process, gearboxes control rotation speed and torque. Unlike standard gearboxes, industrial models feature a longer lifespan and improved safety mechanisms.
When selecting gearboxes for an application, it’s important to understand the different types and their uses.
The Different Types of Industrial Gearboxes
Depending on the needs of various applications, there are several types of industrial gearboxes available.
Explosion proof motors are designed to reduce or eliminate the risks traditional motors present in the presence of combustible materials. Traditional motors feature parts that can spark or generate too much heat in environments with dust and other flammable materials. This poses a significant fire risk that explosion proof motors are designed to negate by being able to fully contain internal explosions and prevent the ignition of larger, combustible atmospheres.
This guide will break down some of the different types of explosion proof motors to help you determine the right one for your facility.
UL Certification — UL674
UL674 is the UL industrial standard for “Electric Motors and Generators for Use in Hazardous (Classified) Locations.”[MAKE LINK OPEN IN NEW TAB] Motors designated as explosion proof should meet this standard’s testing criteria. UL performs a destructive test on each submitted motor to measure its ability to contain and mitigate explosions to different degrees. The results of the test determine which class, division, and group it falls in. This information is displayed on a UL listing identification plate, which is affixed to the motor’s enclosure.
Understanding Hazardous Location Classes, Divisions, and Groups
UL certified explosion proof motors fall into two distinct classes:
Class I. These locations have vapor or gas in high enough concentrations to combust.
Class II. These locations have combustible dust. Class II motors are designed to ensure that the ignition source of the motor and the combustible dust never interact. This means the motor can never reach or exceed the auto-ignition temperature of the dust.
These classes are further divided into different divisions, which include:
Division 1. Division 1 locations contain combustible materials during normal operating conditions.
Division 2. Division 2 locations contain combustible materials only during equipment malfunction.
For example, a Class I, Division 1 location contains combustible vapor or gas during normal operating conditions, whereas a Class I, Division 2 location contains combustible vapor or gas only during equipment faults.
The classes and divisions are further classified into groups based on the type of combustible materials present. Class I groups include:
Group A. Acetylene
Group B. Propylene oxide, hydrogen, ethylene oxide, butadiene, manufactured gases containing more that 30% hydrogen by volume
Group C. Isoprene, cyclopropane, diethyl ether, acetaldehyde, ethylene
Group D. Styrene, ammonia, acetone, methane, benzene, ethane, ethanol, butane, gasoline, propane
Class II groups include:
Group E. Magnesium, aluminum, and other metal dusts with similar properties
Group F. Coal
Group G. Wheat flour, nylon, corn, polyethylene, wheat, sugar
If a UL listing identification plate indicates that a motor is a Class 1, Division 1, Group C and D explosion proof motor, that means it can prevent explosions in areas that contain Group C and D combustible materials during normal operating conditions.
Selecting the Best Explosion Proof Motor Type for Your Application
When determining the right explosion proof motor for your specific application, it’s important to determine the division and class of your environment. Your local safety authorities can help with this. If you have a Class I, Division 1 location, you need a motor that is fully capable of containing internal explosions. If you have a Class II, Division 1 location, it’s important to choose a motor with a casing that can keep the surface cool. Division I motors can handle both Divisions I and II locations, in the event of any doubt about your location’s identification.
Quality Explosion Proof Electric Motor Solutions
At GIE, we provide the following hazardous duty explosion proof motors:
These motors are rated for Division I locations. Their single-phase design makes them best suited for general-purpose and residential applications.
Three Phase Hazardous Duty Explosion Proof Motors
Our hazardous duty three-phase motors are built to withstand more demanding operating conditions compared to general-purpose motors. All of these motors are suitable for Division I locations, but we also offer individual models that are suitable for Class I and Class II locations with Group C, D, E, F, and G hazardous materials. Their three-phase design makes them ideal for more extreme environments, such as factories and other industrial facilities.
Contact Us for Your Explosion Proof Motor Needs
Properly rated explosion proof motors keep your facility safe when spontaneous ignition and combustion are a risk. Contact us today to learn more about our available motors or request a quote for pricing details.
Electric motors are electromechanical devices that convert electrical energy into mechanical energy to power connected equipment. They can be classified in many ways depending on their design and construction. Regarding the number of power source phases, they can be categorized as single-phase or three-phase. While there are some similarities between the two, there are also many differences. Each has unique operating and performance characteristics that make it suitable for particular types of applications.
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The electric motor experts at Gainesville have put together the following guide to single-phase and three-phase motors to help readers understand which one is best for them. It covers the differences between them, highlighting how they work, types available, key advantages, and common applications.
Differences Between Single-Phase and Three-Phase Motors
In any motor application, it is important to choose the type you use carefully. If the motor is too small, it can cause electrical stresses that lead to premature motor failure. If the motor is too powerful, it can cause damage to the equipment and unnecessary power waste. Depending on the requirements and restrictions of the application, the wrong motor can also lead to many other issues.
For these reasons, it is important to know which motors are suitable for which applications. The first step is understanding how they work and what advantages they offer. Let’s take a look at single-phase motors and three-phase motors.
What Is a Single-Phase Motor?
A single-phase electric motor uses a single-phase power supply to convert electric energy into mechanical energy. It contains two wires (one hot wire and one neutral wire) and uses a single alternating voltage. Since it only generates an alternate field, it needs a capacitor for startup.
Single-phase motors can provide power of up to 10 hp. However, they are typically small in size and offer limited torque capacities.
Like any other pump, submersible pumps are used to move fluid from one point to another; however, they are completely submerged in the fluid or medium they are required to pump. This type of pump features a hermetically sealed motor that is close-coupled to the pump body, which is contained in a water-tight enclosure to prevent the entry of liquid and to protect the motor from damage.
Submersible pumps work by using the head of fluid to push it forward rather than pull it up. This pumping process is extremely efficient because it requires no energy. A submersible pump’s motor is cooled by the fluid around it to prevent overheating.
In many fluid pumping applications, pumps have to be placed above the level of liquid, allowing air into the line, which can lead to challenges such as overheating and pump failure. To avoid these issues, self-priming pumps are used to evacuate the air before moving liquids. At Gainesville Industrial Electric (GIE), we offer a variety of self-priming pumps to suit the needs of various applications.
Self-Priming Pumps 101
What Is Self-Priming?
Pumps that are partially or completely above the fluid level allow air into the suction line, which must be evacuated or displaced before the pump can move the liquid. Self-priming pumps are capable of removing air at startup before beginning its normal pumping functions.
Are Centrifugal Pumps Self-Priming?
Centrifugal pumps do not have seals between the suction and discharge sides of the pump, meaning they are not self-priming and cannot evacuate gases and air if the pump is above fluid level. To make a centrifugal pump self-priming, it can be surrounded by a tank to ensure that it is always immersed in a liquid and that it has the necessary lubrication and cooling to prevent the pump from overheating.
How Do Self-Priming Pumps Work?
To avoid the mixing of air and water, self-priming pumps create a partial vacuum to discharge water while also evacuating any air. It does this by combining the air and water during the priming process, forcing the air to rise and the water to sink or go down. Gravity then pulls the air-free water back into the impeller, where it mixes with the remaining air in the suction line.
This process repeats until all air is evacuated and a vacuum forms in the suction line. Once this happens, atmospheric pressure forces the water into the suction line and towards the impeller to allow pumping to begin.
Self-priming pumps are used in various industrial and commercial facilities, from steel mills, power plants, and sewage treatment facilities to wineries, breweries, and more. Common applications include:
Pumping water, fuels, clear or gray water, raw sewage, industrial wastewater, and more
Liquid transfer systems
Basement floodwater pumps
Bailing out boats
Increasing water pressure
Self-Priming Pump Solutions
At GIE, we offer the following self-priming pump solutions:
FPS self-priming pumps are built to handle clear water and solids. They can handle solids up to 3 inches in diameter or length, and the pumps are built with self-priming mechanisms to mitigate the risk of becoming air-bound. At GIE, we provide FPS self-priming pumps in electric drive, frame mount drive, and gas engine drive varieties. Gas engine varieties can provide up to 27 horsepower, depending on the model.
These self-priming pumps can handle clear water for a variety of commercial and industrial applications. They are available in portable contractor pump styles, with enclosed impellers, and with bronze fittings to integrate with virtually any applicable system. Gould’s self-priming end suction pumps can handle up to 250 PSI and fluid temperatures of 250°F.
These self-priming pumps are designed to be placed anywhere from 10 to 20 feet above the fluid level without the risk of becoming air-bound. Along with clear water, they can handle solids of different sizes depending on the specific model chosen. Marlow specializes in vertical in-line pumps that can be used in industrial petroleum and chemical systems.
Contact GIE for Your Pump Needs
Self-priming pumps are crucial in ensuring that air does not interfere with pumping operations. At GIE, we have been providing high quality industrial electric motors, pumps, parts, and various repair and maintenance services since 1959. Our experienced staff and commitment to quality ensures products that meet or exceed customer expectations. To learn more about our self-priming pumps, contact us or request a quote today.
Centrifugal and positive displacement pumps are powerful tools that can move fluid through complex industrial and municipal systems. But it’s essential to choose the right equipment for your facility’s needs. Here, we’ll discuss the differences between the two pump types, the fluids they can handle, and some of the most popular applications of each pump.
Difference Between Centrifugal Pumps and Positive Displacement Pumps
. Fluid Transfer Mechanisms
Both centrifugal and positive displacement pumps transfer water from an inlet point to an outlet point at a controlled degree of force and quantity. However, the mechanisms they use are different. Positive displacement pumps draw fluid into a cavity, or displace the fluid, and then force the fluid out of the cavity through suction. Centrifugal, or aerodynamic, pumps have a spinning impeller that draws the fluid into the pump and forces it out of the outlet point at an increased velocity.
. Types of Fluid Transferred
Each type of pump works best with different types of fluid. Positive displacement pumps can handle highly viscous fluids, and their flow rate can increase as the fluid gets thicker. Centrifugal pumps, on the other hand, can’t handle viscous fluids as well because of the frictional losses. Also, positive displacement pumps can handle shear sensitive fluids—or fluids that change when force, stress, or pressure is applied—whereas centrifugal pumps cannot; the impellers present a risk to the fluid. Positive displacement pumps can also handle intermittently dry periods and can start without being primed by liquid in the system. Centrifugal pumps need liquid in the unit to kick-start the pressurized control.
There are several different types of positive displacement and centrifugal pumps, each of which uses slightly different mechanisms and can handle different loads but which still uses the basic concepts of positive displacement and rotational force to cause movement. Facilities should first decide whether a positive displacement or centrifugal pump is the best choice based on pressure and flow rate demands, the type of fluid being moved, and the required suction lift before choosing a specific pump type and model.
Pump Performance Comparison
One of the key differences between the performance of positive displacement and centrifugal pumps is the flow rate. Positive displacement pumps maintain a constant flow rate, even as pressure changes, but the fluid moving out of centrifugal pumps is a varying flow rate based on pressure.
. When to Use a Centrifugal Pump?
Centrifugal pumps excel at pumping thin liquids with low viscosity levels. These include water, thin oils and fuels, and chemicals. They’re the most commonly used category of pump for high-volume applications that demand high flow rates at low pressures. Some popular applications include:
Municipal water and water supply systems
Air conditioners and water circulators
Petrochemical and light fuel transfer stations
With a vortex impeller, centrifugal pumps can even handle some fluids with solids. However, they work best when pumping consistent high-volume quantities of water.
. When to Use a Positive Displacement Pump?
Positive displacement pumps, on the other hand, excel at high-pressure and low flow rate applications with viscous fluids. These pumps work well in the following applications:
Municipal sewage systems
Oil processing centers
Manufacturing centers that produce or process thick pastes and other viscous materials
Complex facilities such as food processing plants and other manufacturing facilities benefit from a mix of both types of pumps. Food processing operations will need centrifugal pumps for adding water to batches, for example, but need positive displacement pumps to control the movement of thicker compounds. Oil processing centers may need positive displacement pumps for processing crude oil while they can use centrifugal pumps for handling thinner, lighter by-products.
Quality Pumps From Gainesville Industrial Electric
At Gainesville Industrial Electric, we work hard to provide the right pump for the job. Since 1959, we’ve specialized in providing high-quality motors, pumps, gearboxes, and drives to industrial clients across multiple industries.
Industrial pumps are designed specifically for use in harsh or heavy-duty applications. They move a range of material types, including water and wastewater, chemicals, oil, petroleum, sludges and slurries, and food. This overview of pump varieties and applications will lend insight into which pumps are best suited for certain jobs. (more…)
Variable frequency drives (VFDs)—also referred to as AC drives, variable speed drives, inverters, and motor drives—regulate the voltage and frequency that a power supply delivers to a connected motor. These controller devices are suitable for use with single-phase and three-phase motors, adjusting their output speed to enhance process operations and energy efficiency. (more…)