Impeller 17 Refurbishing Coles Myer with E.C. Moving Forward with an E.C. Backward Curved Combination E.C. Making a World of Difference Cheap Widget...! How Much Did You Save? Easing an Exhausted Hood with E.C. www.ebmpapst.com.au Refurbishing Coles Myer with E.C. When Coles Myer set out to improve the efficiency of their supermarket refrigeration plants, the latest ebm-papst EC products were called upon to help. Coles Myer chose their Ringwood supermarket for a test installation of 14 x 800 mm diameter EC condenser fans (refrigeration condensers). Their objective was simple: reduce energy consumption in accordance with stated company policy; reduce noise pollution; maximise benefits of the fan laws; maximise efficiency of the refrigeration system; and simplify the installation. Mission impossible? Well, for starters, it is anticipated that the new EC installation at Ringwood will exceed 50% in energy savings. How so? Unlike normal motors, the EC motor efficiency remains relatively constant across its speed range. The condenser fans infinitely adjust speed to equal the load on the system. And since the power driving a fan is proportional to the cube of the speed, when fan speed matches the everchanging duty, substantial operating savings are made readily available. Coles Myer were concerned about the operation of large fans in residential locations generating noise pollution. The starting and stopping, high-speed operation, the inherent noise of the electric motor – especially when speed controlled with frequency invertors – all culminate to create this potential problem. But the ebm-papst EC fans attacked all these areas of concern. For starters, the fans ramp up in speed with no ‘start up’ noise, operating at maximum speed (which can be limited if need be) only when the plant is at maximum capacity. Plus, as a result of the speed control function, the EC motors have no audible sound. With regard to efficiency of the entire refrigeration system, each of the 14 x 800mm diameter EC fans are fully speed controlled by a 0 to 10 volt signal. Therefore, by the supply of a 0 to 10 volt signal from the pressure sensor, the condensing temperature of the refrigeration system can be kept constant throughout the daily cycle. Lastly, the electronic component of the fan motor allows for functions that are normally executed from additional external components (overload and protection devices, speed controllers) – simplifying the total installation. Mission accomplished! Representatives from Frigrite, ebm-papst and Buffalo Trident inspect the installation. 2 Moving Forward with an E.C. Backward Curved Combination A 7 story building at 130 Little Collins St required 25% more air. On site testing also indicated an increase in pressure to be necessary. “As we have an ongoing involvement in reducing energy use in this building, it would not have been acceptable to use higher fan power input” said Rob Alexander from consultants Genesis Automation. The situation was discussed with Stephen Watson of Fans Direct. Stephen considered the alternatives and recommended the forward curved fan be replaced with 4 x 630mm diameter backward curved ebm-papst EC fans (Fans Direct SCDQ630-EC). The noise factor is also significantly reduced, as the EC / backward curved combination is quieter than the belt driven forward curved combination. Start up is practically inaudible and does not put any pressure on the power supply. Contractor Geoff Proctor said “I’m amazed at the smooth, quiet operation compared to the old fan and the air distribution across the coil is much more even”. Incidentally, the installation and maintenance of the EC fans is much easier, solving any dilemma regarding dimensional restrictions. The old fan had to be cut into sections to remove it, the EC fans just slipped through the access doors. Good choice, Stephen. The backward curved fans are a far better option than the existing forward curved fans, as the belt drive required for a forward curved fan tends to be inefficient, clamorous, and require regular maintenance. What sets the EC motors apart, though, is that they are supplied with built-in speed control, can be tuned to meet the required performance, and, therefore, function much more efficiently than the standard AC motors. “The speed control was an essential component to maximise the performance of the new Dadanco Inffusers” said Rob Alexander. EC Fans behind the filter frame. www.ebmpapst.com.au Performance testing. 3 E.C. Making a World of Difference 1. Introduction By now, it has become almost second nature for most people to save natural resources. This is why companies, too, should face up to their obligation to make their products contribute actively to the care of the environment. As huge numbers of fans are to be found in the most varied of applications, there is an enormous potential for saving energy. Unfortunately, this potential is still not being tapped fully, despite the fact that the simple use of electronics offers this possibility. Nevertheless, the solutions known so far are restricted by three disadvantages: significantly higher costs than conventional solutions, electronics that appear to be complicated and have to be connected separately, plus rather an unsatisfactory noise behaviour. Against this background, ebmpapst as market leader in motors and fans has taken up the challenge and now supplies the market with a complete line of innovative fans that can be connected directly to the mains and which substantially and positively differs from current solutions both in technical and economic terms. 2. Advantages of EC technology for fan applications. Using a classic asynchronous motor is still justified in many applications. However, when used as fan drive, there are quite a few shortcomings to consider, among them: 4 Maximal efficiency of less than 75%, which can, moreover, only be achieved within a narrowly defined speed range. In order to operate at different speeds, designs with different numbers of pairs of poles are required, and thus there is an ever bigger variance. Different motors or motor designs are needed for operation at 50 Hz or 60 Hz. In order to change speeds, additional components (star-delta, transformer, triac control, frequency converter) are needed that result in higher costs, require more space, cause additional losses and lead to higher noise emission. A fan is suited for only one optimal operating point for which it has to be designed precisely - and so the number of variants goes up once more! These disadvantages can be avoided with EC motor technology in the power range of up to 3 kW, and are dealt with here. EC motors are synchronous motors excited by permanent magnets and with phase currents being converted by electronics independent from the rotor position. This principle allows efficiencies of up to 90% across a very wide speed range - and this with the losses caused by the electronics already being taken into account! As the electronics makes it possible to operate the motors at different speeds, there is no longer any need to supply variants with different numbers of pole pairs. This reduces the number of variants for both manufacturer and customers. Their controllability also makes sure that optimal operating points can be set exactly; moreover, the comfortable open and closed loop control possibilities in no way have a negative impact on acoustics, efficiency or system costs! 3. New fan lines Motor type Impeller Ø [mm] M3G074 300 250 M3G084 450 400 350 M3G112 630 560 500 450 M3G150 1000 910 800 710 Fig. 1: New line of energy-saving EC axial fans During the past three years, ebm-papst Mulfingen has developed an entire line of EC motors. This line consists of motors in four sizes, from 100 W to 3 KW. Each size is available in two or three face-to-face dimensions and thus supports a comprehensive range of axial fans with diameters between 250 mm and 1,000 mm and centrifugal fans from 190mm to 630mm diameter. (see figs. 1 & 2) The new motor design also comes in protection type IP54. These EC fans are simple to install: they are fully compatible with and can be used like 3-phase fans - there is no need for additional components. However, the EC fans can also be controlled via linear or BUS interfaces. 4. Potential for saving energy and costs M3G055 190 220 225 M3G074 310 280 250 M3G084 400 355 310 M3G112 500 450 M3G150 630 560 Fig. 2: New line of energy-saving EC centrifugal fans 2000 1800 1600 Power input [Watt] 1400 1200 1000 800 600 3-phase motor with triac 3-phase motor transformer control 3-phase motor with frequency converter EC-Motor 400 200 0 5000 7000 9000 11000 13000 air flow [m3/h] 15000 17000 19000 Fig. 3: Comparison in power input between axial fan in EC technology and axial fan in 3-phase technology in the partial load range. www.ebmpapst.com.au The power input of an axial fan in EC technology is compared to that of an axial 3-phase fan in figure 3, with three different control options. In the maximum air flow range, the EC motor requires 15% less power input than the 3-phase motor, which is due to its better efficiency. When it comes to lower air flows, especially in the partial load range, then the advantage of the EC technology becomes even more pronounced. This is simply due to the fact that the EC motor has a high efficiency across a wide speed range, whereas the efficiency of the 3-phase motor quickly drops with decreasing speed. Power saving in the partial load range is greater than 50% less than the 3-phase motor. Based on an average annual operation time of 4,000 h and the power saving according to fig.3, the annual saving in costs by simply using an EC fan can be calculated easily from fig. 4. These enormous savings in operating costs offered by EC technology have, so far, not been adequately taken into account. Regarding the entire service life, the savings thus 5 E.C. Making a World of Difference gained are substantially higher than the purchasing cost of the EC fan! For operators of plants, the consequence is simple and straightforward: only energy- and cost-saving EC fans should be exclusively used in future. Yet those responsible for setting up a plant were forced, for competitive reasons, to go for speed-variable fans in 3phase design as EC solutions available up to now have been more expensive than the conventional types. The new ebm-papst line marks the beginning of a new era: suddenly, purchasing costs of EC solutions are at the same level as the purchasing costs of technically comparable 3phase solutions. Cost savings that normally do not get considered are to be found on the logistic side of things: EC fans can be operated without any need for modifications on power supplies with different frequency, and the operating point can be set via speed variation. For this reason, it is possible to replace a large variety of 3-phase fans with just one EC fan. Savings in energy Annual energy savings ($) Whenever a 3-phase fan is operated with triac control or frequency converter, the noise behaviour in the partial load range is negatively influenced. This is illustrated in fig. 5, and comes as a result of the oscillations in the electromagnetic fields and deviations in electric conductance which form electro-magnetic harmonics with their resulting power and torque excitations. The fan emits them in the form of air-borne or structure-borne noise. So far, and from an acoustic point of view, the most effective case has been operating a 3-phase fan with a transformer. The most beneficial noise behaviour can be achieved with EC fans. 6. Summary With this newly developed and complete line of ebm-papst EC technology with integrated electronics, there is an intelligent and compact alternative for speed variable fans. The new products offer a substantial potential for energy savings, with the purchase costs being paid off quickly, as operating costs can be reduced substantially. Compared to alternative infinite speed control options EC fans do not generate increased noise. LpA [dB] 600 75 70 500 800 W 800W 400 300 200 65 600 W 600W 60 400 W 400W 50 55 45 100 0 0.06 5. Noise behaviour of the new fan lines 3-phase motor with frequency converter 3-phase motor with triac 3-phase transformer control EC-Motor 40 35 0.07 0.08 0.09 0.1 0.11 0.12 0.13 0.14 Energy costs ($/kWh) Fig. 4: Saving in operating costs by using EC fans, at an operating time of 4,000 h/a. 30 25 20 2000 4000 6000 8000 10000 12000 14000 16000 V[m^3/h] Fig. 5: Comparison of noise behaviour between axial fans in 3-phase technology and an axial fan in EC technology. 6 Cheap Widget...! How Much Did You Save? Ever heard the old saying: ‘If the price sounds too good to be true, then it probably is’? Then, how many times have you heard, ‘We can’t complete the product because the widget hasn’t arrived’? And when it does arrive: ‘Nope. It’s the wrong widget!’ Or, after assembling the product: ‘The wretched widget doesn’t work. Pull it apart, get a new one.’ Now imagine you have a factory floor cluttered with incomplete products. You’ve incurred costs such as excess labour, the production line having been interrupted, not to mention now having to rework the product. But wait – there’s more! Who’s going to stand sweating in front of the customer explaining the reason for belated delivery time? Who’s going to pay the administration staff, since they’ll be busy punching away at the keyboard getting things back in order? Sure, it was a cheap widget. But now it’s really stuffed you up, it’s going to cost the business much more than you had realised. Of course, accidents will happen. That’s life. But it is no accident that the major manufacturers around the world use ebm-papst products. Quality of both product and service is what makes us the market leader. We make certain that, if, indeed, a situation occurs, systems and procedures will be implemented to ensure customer satisfaction. Recommended MRP CUSTOMER MRP SYSTEM MRP Change Advice The MRP assists customers with forecasting their requirements. This is done by analysis of historical usage in order to predict future usage, leaving the customer to make any necessary adjustments. Every time there is a change, an email is automatically sent to inform the customer of the MRP status. That’s why when ebm-papst receives an order and enters it into the system, an email is sent to the customer that evening listing details and delivery date of the product (Order Confirmation Report). This way the customer can check this against the order and confirm whether it is correct. Stock is thus allocated and reserved against the order. Thanks to the OCR and a diligent emailing system, the days of getting wires crossed are over. Clear communication is essential, especially when an error occurs. To make good decisions you need to know where you stand. Moreover, the customer can rest assured that we at ebm-papst are ever mindful of his needs through the MRP forecasting system. In other words, we have made it our business to minimise all potential breakdowns. Each night the system checks for any changes to the delivery date, in case the customer has requested it, or a ship has been held up, or for whatever reason. If there has been a change, the system will automatically notify the customer via email. The sales manager also receives a copy, advising him to investigate and, if possible, take remedial action. Once again the system will send the customer an email if such action is taken. These are just some of the systems that increase the value of ebm-papst’s widgets. They come at no cost to our customers. Armed with this information customers can make decisions that make for an effective cost reduction. But just how much depends on whether or not an organised and responsive system is put in place. Back to the Future with an MRP (Materials Requirement Plan) OEM’s require a continuous supply of product, even though quantities may vary depending on sales. It is why ebm-papst has implemented a highly sophisticated MRP system for each customer and product. Ask one of our sales staff why we do a stock count not just annually but every day. SALES DEPT. er Ord e ng ha C r me sto Cu Order Sales Dept. Change O.C.R We’ll confirm our every move. How often is it that a customer will be kept in the dark concerning a late delivery until after the scheduled delivery date? Customer Change CUSTOMER Date Change Notification ebm-papst DELIVERY SYSTEM SHIPPING OR EXTERNAL CHANGE Annoying, really. www.ebmpapst.com.au 7 ebm-papst Australia Pty Ltd VICTORIA 59-67 Export Drive Brooklyn Victoria 3025 Phone 03 9315 2011 Fax 03 9315 1282 Email sales@ebmpapst.com.au www.ebmpapst.com.au Easing an Exhausted Hood with E.C. QUEENSLAND Phone Fax 07 3246 5441 07 3246 5447 NEW SOUTH WALES Phone Fax 02 9605 0090 02 9618 1833 SOUTH AUSTRALIA Phone Fax I recently had a discussion with a ‘hood’ manufacturer on a project. It had to do with the owner/operators of the project, and how they had encountered problems with the exhaust fan in relation to their cooking equipment. 08 8336 3544 08 8336 4755 WESTERN AUSTRALIA Phone Fax 1800 066 300 03 9315 1282 NEW ZEALAND Phone Fax 09 835 2614 09 835 2619 EC Fan Please add me to the ebm-papst Impeller newsletter mailing list. Now because the high air quantity of the hood is designed for maximum load, it tends to cool the product during certain parts of the cooking process. This results in an increase of energy use, as the cooling of the product will now require more cooking time. Moreover, the operation of the hood leaches air from the surrounding area’s air-conditioning system. This causes another problem, as the increased ingress of outside air means more associated costs with the air conditioning system having to either heat or cool it. Name It all makes for one very expensive hood. The solution, however, is simple. Position Company Name Address Temperature Sensor Postcode In this situation one should use a variable speed, EC exhaust fan. By connecting the EC fan to a temperature probe inside the exhaust hood, one can commission it to commence operation at the slowest speed if the hood temp, for example, exceeds the ambient kitchen temperature by say 5 degrees. And, likewise, commission the EC fan to operate at maximum speed when the hood temp reaches a predetermined temp (e.g. 15 degrees above kitchen temperature). Not only will the fan only operate when it is needed, at the capacity it is needed, it will do it all automatically. Telephone Problem solved. Email Please The cooking equipment is located in a retail shop in a shopping centre, and operates intermittently throughout business hours. The staff turn on the hood exhaust fan as soon as they commence cooking; hitherto, the fan will run at maximum speed for the rest of the day, thus consuming power unnecessarily. Post Mail 8