ebm-papst Fans, Blowers and Technology

By Matt Menard, Market Manager - Air Conditioning

Remember the hotel room where you barely slept because the AC constantly cycled on and off?  

The HVAC systems in our homes, offices, hotels and other buildings should keep us comfortable no matter what the weather is outside. And while we expect these systems to perform on demand, we certainly don’t want to hear them running.

What strategies can we help supress the sound and vibration of essential HVAC components?

Internal compressors and fans are the main sources of noise. If the fan’s rattling or the compressor’s banging, clanking, hissing or rattling, getting the system inspected and serviced should be your first priority.

However, cooled air that moves through systems and ducts can create additional sounds. These noises may require a variety of approaches that building HVAC and maintenance pros can address during design, installation or retrofitting.

Size It Right
According to a recent column in HPAC Engineering by Michael Ivanovich of the Air Movement and Control Association International (AMCA), even the most efficient fan will perform poorly if not sized properly.

Mike’s 14-point checklist can help HVAC engineers save energy, reduce noise and maximize efficiency.

Hide It
Any air conditioner that is in a room with people is going to be noisy, which is why most are located elsewhere. Ideally, the only noise that should be heard is that of air flowing into the room.

Placing the air conditioning equipment in a basement, attic or mechanical closet will reduce noise from the mechanical components. In addition, the bulky equipment is hidden from day-to-day life.  

Accessorize
A wide range of products on the market can help reduce HVAC noise. Acoustical wraps or blankets can surround compressors to suppress high-pitched tones. Duct liners absorb noise before it leaves the ductwork. Soft-surfaced insulation can

be used on the inside of the unit cabinet to muffle noise and to provide thermal insulation.

Products such as our AxiTop diffuser and FlowGrid air inlet grill address noise associated with airflow. By reducing the turbulence on the intake of a fan, the FlowGrid minimizes low-tone frequencies commonly associated with large fans. The AxiTop accessory increases the aerodynamic efficiency and reduces sound levels on ebm-papst axial fans.

Slow It Down
The simplest way to reduce the sound levels produced by HVAC systems is to slow them down. By reducing the rotating speed of the motors (fans and compressors), you reduce the motor noise as well as the noise caused by airflow. Our EC motors are equipped with integrated speed-control capability, providing lower noise and energy consumption when slowed down.

What are your HVAC acoustical nightmares, and how are you solving them? Log a comment below!

About Matt Menard
With 12 years’ experience in HVAC systems, Matt Menard, Market Manager – Air Conditioning at ebm-papst Inc., actively supports designers’, manufacturers’ and integrators’ with a wide range of air-moving products. Matt holds a BS in mechanical engineering from Rensselaer Polytechnic Institute. He enjoys skiing, golf and spending time with his wife and two children.

by Matt Menard, Market Manager - Air Conditioning

In the world of HVAC, motors move conditioned air throughout the system. When a motor fails, cooling or heating ceases, leaving occupants of that building uncomfortable. The motor can be replaced relatively quickly with an experienced technician. However, diagnosing what caused the failure is difficult, time consuming and often ignored.

Motor failure is a major headache that can cost building owners significant money. With limited budgets and resources, implementing a preventative maintenance program on motors to minimize failures can be difficult for most. So what is the solution?

The December 9 issue of ACHR News discusses causes and prevention of motor failure. All of these types of failure can be avoided by choosing external rotor EC motor technology, such as is utilized in ebm-papst’s product line, to boost reliability and efficiency.

1. Belt — Belt tension is critical in avoiding vibrations between the fan wheel and motor. Belts tend to stretch throughout their lifetime, so technicians tend to over tighten during replacement. A belt that is too tight overloads the motor and shortens the lifespan. ebm-papst external rotor motors do not use belts—the fan wheel is mounted directly to the motor rotor.

2. Overheating — This is the most common cause of failure. Dirt buildup on the fan wheel and poorly designed/installed ductwork causes additional strain on the motor resulting in overheating and a shortened lifespan. ebm-papst EC motors have temperature sensors built into the internal electronics package that act as a safety device in the case of overheating.

3. Electrical Fluting — When utilizing a Variable Frequency Drive (VFD) for speed control, users can experience a phenomenon called electrical fluting, which basically equates to a mini-lightning storm that occurs within the motor as voltage and frequency are regulated by the VFD. This ‘storm’ affects the bearings, resulting in premature failure. Electrical fluting is unpredictable and requires additional measures such as shaft grounding kits and ceramic bearings to prevent. ebm-papst EC motors have built-in speed control and do not require a VFD, eliminating the electrical fluting issue.

In addition to eliminating belts, adding temperature sensors and built-in speed control, industry experts such as Jim Connell of AirXChange Inc. believes that ECM fans are more reliable and use less energy than traditional AC motors and drives.  Utilizing external rotor EC motor technology provides not only the most reliable, but most efficient technology available.

By Matt Menard, Market Manager - Air Conditioning

Imagine it’s a sweltering day, and you’ve entered a nice cool office building, school, hospital or large retail store. Aaah. Now imagine you’ve entered that same building but the air conditioning’s not working. Would you accept that the building’s owners shut it off to be green and consume less energy?

Given that 40% of commercial building utility bills go to power their HVAC systems, manufacturers are placing a strong emphasis on energy efficiency in product design for the rooftop units that move the cool (and hot) air that keeps us comfortable at work, in school, and at play.

Ranging from 3 to 175 tons, rooftop HVAC systems provide a turnkey solution, and can be installed on most large buildings. All components of the system, including fans, compressors, coils, electronics and filters are packed tightly into the unit, making installation, operation, and maintenance as simple as possible.

To meet the energy-saving specifications of HVAC system manufacturers, component suppliers have improved the efficiency and operation of the compressors, motors, fans, gas/electric heating devices and controls inside them.

Within rooftop units, compressors and fan motors consume the most energy. However, both have changed dramatically. Compressors have been transformed from inefficient, single speed devices to variable speed devices with electronic controls, making them 40 percent more efficient than their predecessors.

Similarly, fan motors have evolved from inefficient, single-speed units to variable speed, highly efficient designs. For example, the ebm-papst external rotor EC motor touts an efficiency of 90%.

If you’re responsible for keeping HVAC costs down in your building, this is great news. However, motor and compressor technology is nearing the limits of efficient design. Meanwhile, state and federal minimum energy standards are becoming more stringent.

As the mechanical components within HVAC systems begin to hit their efficiency limits, OEM’s are looking to computer-generated designs that can optimize the heat exchangers and aerodynamics in packaged rooftop systems.

Evolving the heat exchanger
Recent work by the NIST (National Institute of Standards and Technology) is focused on air conditioning heat exchangers.  Using computer generated design and analysis, they produced a unique heat exchanger design that yielded an 8% gain in efficiency for the heat exchanger and a 3% gain in overall unit performance. OEM manufacturers are actively pursuing these ultra-efficient designs. They’re also utilizing materials such as aluminum instead of copper in new heat exchangers to reduce cost and improve efficiency.

Evolving the fan
While current fan motor technology is up to 90% efficient, the blades and impellers within a fan are aerodynamically inefficient. Forward curved fans, used in indoor applications, are about 50% efficient. Axial fans, used in outdoor applications, are between 30 and 40% efficient.

Offering expertise in EC motors and aerodynamic design, ebm-papst is working to boost the efficiency of future products through computer generated design and analysis. We’re also working closely with our OEM partners to test new blade and impeller configurations within rooftop HVAC systems, with the goal of reducing power consumption and lowering operating costs to meet their customers’ needs.  So now imagine being green and keeping the air conditioning on! 

Armin Hauer, Advanced Technology Manager

An article in a recent issue of Sustainable Business examines the potential impact of the uncertain supply of rare earth magnets on manufacturing EC motors, noting that EC technology is reliant on rare earth elements. But this isn’t always the case…  

The manufacturers of electric motors struggle to predict the future costs of rare earth elements. As a result, user circles often regard permanently excited electric motors, which are particularly energy-efficient, as expensive. But highly efficient electric drives don’t necessarily depend on strong rare earth magnets. For example, "simple", cost-effective and – above all – readily available ferrite magnets suffice for energy-saving EC fan motors with an external rotor design. In some cases, these reach motor efficiencies of more than 90 percent.

How an EC motor works

A brushless DC drive (BLDC motor), a BLPM motor or an electronically commutated (EC) motor – exactly which motors are in the rare earth element discussion? These are all actually different names for permanently excited synchronous motors. These motors use electronic drives that are either AC line-powered or that use DC power supplies. The BLDC/BLPM motors usually operate with square-wave currents (block commutation). In contrast, EC motors can operate with both square-wave currents and with sinusoidal currents (sinusoidal commutation). The latter method achieves a significant noise and vibration reduction over the block commutation method. The design with sinusoidal currents corresponds to the classic synchronous motor.

Exploded view: The permanently excited synchronous motor, also called brushless direct current motor or EC motor.

An EC motor always requires a drive electronic that includes an inverter for the control of sequential and reversing current flows in all cores of the armature. This electronic commutation determines the strength and rotational speed of the resulting magnetic field that the armature generates. The permanent magnet rotor responds by revolving synchronously with the rotary field of the armature. In contrast, the speed of AC line-powered asynchronous motors depends on the frequency of the supply voltage and on the motor load. The torque-speed characteristic of an EC motor mimics a DC shunt motor, because both motor voltage and shaft speed, as well as motor current and shaft torque, correlate linearly. The angular rotor position is continuously determined by either sensor hardware in the motor, or the inverter senses the so-called counter-electromotive force and the motor currents for resolving the position mathematically. The idle motor speed depends on the applied voltage and the number of turns of the armature windings. Within the physical parameters of output power, torque and temperature exposure, nearly arbitrary motor speeds can be reached slip-free and synchronously with the rotating magnetic field. These speeds are completely independent of the AC line frequency.

Dynamic requirements determine magnet choice

As a result of their unique motor characteristics, external rotor EC fans seldom need strong rare earth elements. That type of magnetic quality is really only needed to minimize the moment of inertia for very dynamic servo motors.

Why our EC motors don’t need rare earth magnets

ebm-papst GreenTech EC motors for energy-efficient fans remain undisturbed by rare earth element scarcity, because the armature of a GreenTech EC motor is located inside and is surrounded by the rotor.

Cutaway: Centrifugal fan with external rotor motor.

Our energy-efficient fans remain undisturbed by rare earth element scarcity because the arrangement with external rotor motor achieves a higher torque than an internal rotor motor of the same size, magnet system and magnet thickness. An internal rotor motor has a restricted magnet volume, a reduced air gap surface and smaller radius. External rotor motors that use hard ferrite magnets cleverly applied to fans and blowers attain torque and efficiency levels that internal rotor motors can achieve only with rare earth magnets, due to limited volume and size.

A fan motor design with an external rotor has an additional advantage: The fan impeller mounts directly to the outer rotor, directly to the motor "housing". The result is a compact axial length and superior self-cooling of the external rotor motor.

To further discuss how our EC motors are different, contact us.

Dr Jürgen Schöne, R&D Director of Aerodynamics and Motor Technology at ebm-papst Mulfingen,Werner Müller, Manager of Motor Development at ebm-papst Mulfingen, Armin Hauer, Advanced Technology Manager at ebm-papst Inc.

by Phil Hartman, Senior Director of Marketing

On September 13, 40-50 members of the Connecticut ASHRAE chapter paid ebm-papst a visit in Farmington for a technical session. These sessions are held once a month from September through May; consisting of a technical session given by a host company, social hour, dinner, and presentations by the host company. They are an  opportunity for members to learn more about other companies and their products, and for the host company to showcase their expertise.

Those who arrived early were able to visit our new showroom and view our extensive range of products, including fans, blowers, and value-added assemblies.

To start our technical session we divided into two groups for tours – one of our manufacturing area led by Brian Ladegard, Director of Operations, and the other of our test lab, including airflow and acoustic testing areas, led by Scott Beauchemin, Vice President of Engineering. 

In the manufacturing areas, participants were able to see a variety of processes, such as sheet metal punching, bending, forming, painting, assembly and end-of-line testing.

In the lab and testing areas, Scott described the testing we are capable of for air moving devices with focus on our air test and acoustic chambers.  Participants were able to see actual customer units currently being tested. 

After the tours, the group reconvened at the Farmington Marriott for a social hour, dinner, and presentations by Armin Hauer, Advanced Technology Manager and Tom Costello, Market Manager - Heating.  Armin covered the latest fan & EC motor technology for buildings, fan efficiency metrics and the latest fan energy legislation.  Tom focused on gas component and system technology used in high efficiency residential and commercial gas fired condensing boilers, with emphasis on comparing pneumatic and electronic GARC (gas-air-ratio-control) technology.

Many thanks to Armin Hauer, an active ASHRAE member himself, for being instrumental in making this possible and for providing guidance for the content.  This was our first time hosting an ASHRAE tech session, and based on the feedback we received, the group found the tours and presentations to be informative and interesting.  It was our pleasure to host and we thank ASHRAE for their assistance and participation with this event!

If you work in a climate controlled office cubicle with a low ceiling, the mystical term “thermal destratification” may never play a role in your comfort or productivity.

However, if you’re on a production floor or in a warehouse that swelters in the summer and freezes in the winter, shivered or sweated in an enclosed stadium or mall, or peered into a frost-covered grocer’s freezer, you may appreciate the benefits of a device that evens out temperatures by continually exchanging a building’s hot top air layer with cooler, lower layers.

Nine years ago, entrepreneur Ray Avedon, president of Longmont, Colorado-based Avedon Engineering and founder of Airius LLC, invented the turbine-shaped Air Pear Thermal Equalizer® to solve air flow problems and to save energy at his contract manufacturing facilities.

 Ray Avedon with the AirPear

He hit upon a novel design and concept for a ceiling mounted air mover that would meet the needs of enclosed spaces – manufacturing facilities, warehouses, groceries, aircraft hangers and gymnasiums – that needed to stabilize temperature and humidity levels. 

The energy efficient air turbine, named the Air Pear® by Airius for its appealing shape, was born. Initially developed in five models offering progressive voltage and size options, the more than 30,000 Air Pear® systems that have been installed since 2004 have been saving buildings — such Siemens Transportation Systems’ rail maintenance facilities in Acton, UK — 35 percent or more on energy costs with an ROI of 12 to 36 months.

Before 2006, Airius sourced internal fan assemblies for its Air Pear systems from a low technology manufacturer. Airius had to meet specific regulations by the Food and Drug Administration (FDA) stipulating that pharmaceutical warehouse temperatures vary by no more than two degrees from ceiling to floor. The company needed to work with a manufacturer that would be able to deliver a dependable, controllable fan that would meet FDA’s stringent requirements.

Enter ebm-papst, Inc., the North American headquarters for ebm-papst, a global manufacturer of energy efficient air moving systems.

“At our request, ebm-papst came up with a special fan motor – the EC motor – to facilitate our marketing with the pharmaceutical industry. That motor series is now the norm for our Air Pear destratification product line,” expained Avedon.

“The beauty of our axial fans’ EC motor is that everything can be remotely controlled. There are no separate motor speeds to hassle with … meaning dependable consistent ventilation and ease for the customer,” said Randy Rau, ebm-papst’s Denver-based sales engineer.

Six years later, Airius utilizes ebm-papst fans in 75 percent of its Air Pear systems. According to Rau, linked arrays of remotely controlled Air Pears that incorporate ebm-papst EC axial fans are installed in hundreds of applications.

The customers are diverse; Air Pear usage ranges from warehouses and plants to grocery stores, movie theaters, even a dairy producer that keeps its cows cool to increase milk production. Air Pear Model 45s are being used to equalize temperature and humidity in Washington D.C.’s botanical garden and soon will be installed at Hartford, Conn./Springfield, Mass.’s Bradley Airport. The larger Air Pear Model 100s are installed in aircraft hangers, large atriums, retail malls and sports stadiums.

As part of its GreenTech commitment to energy efficiency, ebm-papst Inc.’s U.S. headquarters in Farmington, Conn. recently installed 12 Air Pear units in an area that formerly served as warehouse space and now houses the company’s assembly operations. According to ebm-papst Director of Manufacturing Brian Ladegard, the units, which are wired to be controlled as one collective “node” as well as operate independently, serve three purposes.

“The Air Pear units will help keep employees in our assembly building comfortable during winter months by circulating warm air to floor level,” said Ladegard. “We anticipate saving on energy costs by equalizing temperatures in this building. And because ebm-papst’s fans and motors are at the heart of the Air Pear Thermal Equalizers, observing them operate in our facility allows us to conduct practical on-site research and development and offer new configurations to Airius that can help them reach new markets.”

by Joe Landrette, Market Manager at ebm-papst.

The US consumes about 4.40 trillion kWh of electric energy (Tomorrow is Greener 10/2011). Two percent of that power consumption, or 88 billion kWh, is used by data centers, which provide us with services like Apple's iCloud or Microsoft’s SkyDrive.

Because power savings is critical for hardware manufacturers and their customers, many companies are migrating from large facility data centers to portable/modular data centers that are often set up within sea containers. This new generation of data center is often fitted to house many racks of IT equipment that have ultra efficient cooling systems inside.

Not only can modular/portable data centers be manufactured and deployed more rapidly than traditional data centers, they also employ cooling solutions that can be 30 times more efficient than facility-style cooling systems and can save up to $500,000 a year in energy costs!

Because the majority of portable and modular data centers don’t have the same heat/cooling duct losses experienced in traditional data centers, the new configurations can super-charge their energy efficiency by incorporating ebm-papst’s range of EC blowers and fans, from our small 80mm fans up to 1250mm models.

The new modular/portable data centers also provide an opportunity for ebm-papst Inc. to offer builders air flow and design management strategies and custom sheet metal assemblies. Our products and engineering support services are helping shape how data centers are joining the earth-friendly movement and changing the future of both indoor and outdoor data storage.

For more information on Data Centers, contact Joe Landrette at Joe.Landrette@us.ebmpapst.com or call ebm-papst at 860-674-1515

The AHR Expo is the largest HVAC&R trade show we exhibit in, and it’s coming up fast. With less then a month to go, it's getting a little crazy in the Marketing department! Preparations have become a daily occurence at ebm-papst - we even dream about AHR. Along with packing extra clothes to keep warm during a visit to the Windy City in January, we'll be bringing many of our products used in the HVAC&R market.

Some featured products will include:

• HyBlade (www.ebmpapst.com/hyblade)

• RadiCal (info.ebmpapst.com/RadiCal)

• i-Maxx (info.ebmpapst.com/i-maxx)

• Plenum (Plug) Fan (info.ebmpapst.com/plenum)

This week, literature, promotional giveaways and bottled water (in case our visitors get thirsty) are being packed up and shipped to our new display company, DisplayCraft. Once they receive this last batch of supplies, the whole booth will be sent on it's journey to Chicago!

This year's booth will be a little different from our past booths at AHR, thanks to DisplayCraft! They've helped up redesign the layout of the exhibit to make it more spacious and functional. We're very excited to see the final result at the show on January 23rd-25th!

Throughout the show, expert ebm-papst Market Management teams that represent each industry will be there to expertly solve any air moving problems you might have!

For anyone who wants to do a little homework before visiting the ebm-papst booth (#2046) at AHR, here is a selection of some of the literature that will be available.

• VACR
• Heating
• GreenTech EC Technology

Click here to register for the show!

We hope to see you there!

 There are three types of AC motors that are used to drive fans – 3-phase motors, permanent split capacitor (PSC) motors and shaded pole motors.  The type of motor required for a given application is dictated by the input voltage available in the application and the amount of power required to drive the fan. 

• PSC and shaded pole motors are used for single phase AC input. 

• Shaded pole motors are suited for low power fans. 

• A more powerful single phase fan requires a PSC motor.

• Shaded pole motors are more cost effective but are limited by their lower power. 

• PSC motors require an external capacitor for proper operation. 

• A 3-phase AC motor is needed when the application has 3-phase AC input.

  When the application requires DC input, a brushless DC motor is typically used. A brushless DC motor uses an electronic circuit and permanent magnets to generate rotation. The end result is a highly efficient and highly reliable motor. The commutation electronics are typically built right into the motor so the user only needs to apply DC voltage to the motor. Since brushless DC motors require electronics to function, they are often referred to as Electronically Commutated or EC motors.  Because EC motors have electronics, speed control and speed monitoring functions can be done very easily.  

The last type of motor to discuss is the line-fed EC motor.  These motors are also brushless DC motors but are used with AC voltage. The AC input coming into the motor is rectified to a high voltage DC. These motors are used where typical PSC, shaded pole or three-phase AC motors have historically been used. The benefit of the line fed EC motor is the higher efficiency, controllability and long life that a brushless DC motor offers. All power conversion and drive electronics are located within the motor. 

Campaigns for ‘being green’ are everywhere. The plastic water bottle I’m drinking out of uses about 1/3 of its label just to tell you that they’ve redesigned their bottles in an effort to be green. Here’s an idea, use less paper and make a smaller label. On my desk, a box of all natural sweetener - that’s made of recycled fiber - requests that you recycle it once it’s empty (and I will). More noticeable than that I see green buttons filled with white checks everywhere I look - the symbol for ebm-papst’s own green campaign, GreenTech.   

  Less of a campaign, and more a way of life, GreenTech is a name  put to the philosophy ebm-papst has used for decades. "Each new  product that we develop has to be better than its predecessor in terms of economy and ecology." An example of that philosophy in action is the ACmaxx series. This series started as an attempt to advance the standard technology of the basic  AC fan. The problem with the basic AC fan is its poor efficiency compared to DC technology.

• By giving our fan the ability to operate on AC mains power around the world, while retaining the AC fan’s mounting dimensions, a new standard was created. But this wasn’t good enough.

• While the ACmaxx could fit applications new and old because of its wide voltage range and compact dimensions, there was one problem. Due to the complexity of the electronics, the installation depth couldn’t replace all AC fans. Our next step was streamlining this series into an even better model – the i-Maxx.

The i-Maxx takes the ACmaxx concept to a whole new level.

• By integrating the drive, fan and converter electronics into the motor hub, the i-Maxx has the same dimensions of conventional AC fans, while maintaining the ability to connect to worldwide AC mains.

• We didn’t stop there. The i-maxx is also quieter, more compact, and more efficient than its predecessor. 

This way of life is not just for designing new and more efficient fans. It’s also in practice in the offices and in building the factories, locally and internationally. At the US corporate headquarters in Farmington, CT, and throughout all of the international locations, the employees are urged to recycle, not just bottles and cans, but paper as well, with several paper bins located throughout the office. On of the factories located in Hollenbach, Germany, uses solar power to generate its own energy. The factory was also designed to convert residual heat into a usable ventilation system. Here, at the corporate headquarters in Farmington, a renovation was just completed. Solar panels are up and running, providing our building with lighting that shuts off after a period of inactivity. That will keep us from being too sedentary- but that’s another issue for another company. Many companies are jumping on the green bandwagon, while ebm-papst has been driving.