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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:
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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.
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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
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