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Our Customers
NFO Sinus has advantages in all enviornments.

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”Our customers save up to 70% energy with NFO Sinus”

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”NFO, as the only product on the market, meets all our requirements for interference, at the same time it is very affordable”

- Manufacturing industry for milk production

- World leader in marine manufacturing

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"Patient safety must be put first, which is why we have chosen the NFO inverter for all our hospitals and care centers"

- Healthcare

Region Östergötland
NICOTRA Gebhardt
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"All NFO inverters could be placed in the adjacent maintenence building, which is much appreciated by our operational staff"

- Solutions for warehouse cooling

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”Frequency noise does not exist at all with NFO Sinus. Quiet fans, quiet frequency inverters and quiet motors”

- Fan technology for homes

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”The installation is simpler and cheaper as the NFO don't require shielded cables or have any limitations in cable lengths”

- World-class nanotechnology research

Read more about what our customers thinks about NFO Sinus


Completely interference free environment

NFO Sinus can guarantee a completely interference-free environment,” says Tord Ringenhall, Product Manager at DeLaval International.

DeLaval develops, manufactures and distributes equipment and complete systems for milk production and animal husbandry. The company’s strategy is to offer its customers modern and energy efficient products.

A long-term collaboration agreement has been signed with the Swedish company NFO Drives. The agreement concerns annual deliveries of the interference free NFO Sinus frequency inverter, which will be used to control the speed of electric motors in DeLaval’s own products, including milk pumps and vacuum pumps.

“Cows are sensitive to earth leakage currents and stables and their surroundings also contains technical equipment that is sensitive to electromagnetic interference” says Tord Ringenhall.

“We have tested the NFO inverter for a long time in both laboratory and stable environments in farms around the world and know that it doesn’t cause any electromagnetic interference and neither earth leakage currents nor ball bearing currents. NFO Sinus is therefore entirely suited to DeLaval’s product strategy.”

“We are now using the NFO inverter to control our vacuum pumps but see a range of other applications where we can benefit from the interference free technology,” says Tord Ringenhall.


- With NFO frequency inverters, our customers can save up to 70% energy and with NFO Sinus, which has unique technical properties, we can guarantee that they get a completely interference-free environment, says Tord Ringenhall, product manager at DeLaval.


The DeLaval AMRTM is a new rotary voluntary milking system with a capacity of 800 cows twice a day. The system uses vacuum pumps, which are regulated with frequency inverters for reduced energy consumption and quieter operation.

Anchor 1

Saab Kockums

"NFO Sinus is the first inverter approved for naval vessels,” states Karl-Axel Olsson, who is Manager of Electrical Systems at Saab Kockums in Karlskrona.

“Following extensive testing, both in the lab and at sea, we have now approved NFO Sinus for use in our naval vessels,” reports Karl-Axel Olsson. “This is the first frequency inverter to have been approved.”

Kockums is part of the Saab Group and one of the world’s leading shipyards. The Karlskrona shipyard produces submarines and surface vessels for the Navy, specialising in stealth technology. The vessels have a great deal of advanced technology, which is sensitive to EMC interference. All equipment must therefore be meticulously tested.

One element of risk for the vessels is that in combat or terrorist attacks they may be exposed to dangerous gases, e.g. chlorine or nerve gas. Even in times of peace, gases constitute a risk in the event of fire or accidents in port. To prevent gases penetrating the vessels, overpressure must be created in the cabin. This is done by controlling the speed of the motors in the ventilation system.

“We have not previously been able to use frequency inverters at all,” states Karl-Axel Olsson “All inverters interfered with the sensitive equipment on board and were therefore banned within the Navy.”


“Through market research we got to know about the NFO Sinus frequency inverter. We tested it in our own EMC lab and were impressed with the results. We have also carried out extensive tests at sea. NFO Sinus fulfils all our requirements for interference-free motor control at a very moderate price.”

Anchor 2
Region Östergötland

The electrical systems in health care must be clean. We need to save energy without risking problems with our medical equipment,” says P-O Eliasson, Electrical Systems Developing Manager at Östergötland County Council.

“If you install a conventional PWM-type inverter, you notice it on the network immediately. The earth leakage currents exceed the limits of the earth current monitoring, which have to be raised for equipment to work. That is not acceptable.

“We also avoid the irritating howling motor sound PWM inverters emit. NFO Sinus are both quieter and more reliable.

In Östergötland  County Council there are several big hospitals: Linköping University Hospital,  Norrköping and Motala Hospital as well as a big number of Health Care Centers, Dental Care Centers and Nursing Homes.

Patient safety is paramount, which is why we have chosen NFO Sinus inverters for all our hospitals and care centres at the County Council. They don’t generate any earth leakage currents, so we avoid all interference problems.


P-O Eliasson, Electrical Systems Developing Manager at Östergötland County Council.

Landstinget Östergötland


Patient safety is paramount

Anchor 3

ICA Properties

"The frequency inverters now allow us to control the fans to adapt the air flow to our requirements,” says Malte Enocson, property manager at ICA Fastigheter. “The result is a much more pleasant and much quieter environment”.

ICA’s cold storage warehouse in Långeberga is counted as one of the most modern in Europe. 

“By choosing the NFO Sinus frequency inverter, we have been able to make use of the existing unshielded fan motor cabling as well as place the inverters far away from the motors, just as we wanted,” says Malte Enocson,

property manager at ICA Fastigheter. “The installation was fast and simple, and the inverters are now installed in the electrical distribution box easy for service staff to access.”

ICA’s largest cold storage warehouse, almost 70,000 square metres in size, is located in Långeberga outside Helsingborg. The warehouse, commissioned in 2006, is counted as one of Europe’s most modern FMCG facilities. A huge flow of goods takes place on a daily basis through the 141 doors to supply some 700 ICA shops with frozen products.
At its highest point, it is 15 metres to the warehouse ceiling. A large number of fan units distribute the cold air to constantly maintain a steady temperature of around minus 26°C throughout the entire warehouse.

“Initially we had a lot of problems with noise, draughts and wind gusts from the fan unit and decided as a result to frequency control the fans, partly to improve the working environment but also to save energy,” says Malte Enocson, property manager at ICA Fastigheter.

“Frequency inverters allow us to control the fans so that the air flow is adapted to our requirements. It results in a quieter and more pleasant environment. It was possible to install all the NFO inverters in the adjoining technology building with the other electrical/control equipment used for cold storage, which is much appreciated by our operational staff.


Malte Enocson

Property manager ICA


ICA’s largest cold storage warehouse, almost 70,000 square metres in size.


It is 15 metres up to the ceiling where the fan unit is installed in the cold storage warehouse.

Anchor 4

LKE Lasershowteknik

Safer pump control with residual current device

Using the interference-free NFO technology, the German company LKE LasershowTechnik have better control of their water pumps. Conventional frequency inverters were previously used but there was a problem with the residual current devices always triggering. There are no disruptions with NFO Sinus frequency inverters and the facility is significantly safer.

LKE has extensive experience in using frequency inverters in its facilities erected around the world – such as mobile facilities for major events like anniversary celebrations and sporting events and stationary facilities at amusement parks, etc.

The frequency inverters are used outdoors to control pumps which shoot water cascades to different heights according to a defined program. Each pump is controlled by a frequency inverter and different sizes from 1.5 kW up to 15 kW are used.

The water is lit up with lasers to create different effects and images are projected onto the water cascades. Together they create a spectacular display that is visible to an entire town or park and usually draws large crowds. For safety reasons, residual current devices are required for this type of facility.

“We used conventional PWM inverters before, but then we had extensive problems with the residual current devices always triggering due to earth currents maxing out,” says Matthias Kestler from LKE. “When the show kicked off, it just went swoosh like a pinball machine when all the residual current devices were set off.” We had to have a person on hand just to run around and reset them.

“Now we have used NFO Sinus for some time and are impressed with the technology,” says Matthias Kestler. “With NFO inverters, there are no problems with earth currents and our facility is safer.”


All water pumps are controlled by NFO Sinus frequency inverter. As it is interference free RCDs can be used our facility is safer.

NICOTRA Gebhardt

NFO Sinus sets completely new limits for what a frequency inverter can manage

Ventilation, these days, is considerably more than just a fan which turns. It is a question of requirement adaptation – tailor-made solutions with controlled air flows. Solutions which give tenants in apartment blocks maximum comfort, irrespective of the time of year, says Basse Malmqvist at Nicotra Gebhardt.

New, more stringent demands, have thus meant that many old, belt driven fans in apartment blocks have now been replaced by modern, direct driven

fans with speed control. Nicotra Gebhardt, which has its main market in residential property, is currently working flat out on these conversions.

”But it has not been entirely without problems. Speed control with conventional frequency inverters generates interference and thus requires filters and shielded motor cables. In old buildings, this means extensive and expensive installations.

These days, we can supplement these fans with NFO Sinus – a new technology which sets completely new limits for what a frequency inverter can manage. NFO Sinus guarantees freedom from interference. Freedom from interference which means un-shielded cables and no radio interference filters. The fan is changed and the NFO Sinus can be connected to the existing cable. This is unique.

But there is also another important aspect: What we call frequency noise. The noise which is generated in the motor during all conventional frequency control. This problem is not found at all when we use NFO Sinus. Quiet fans, quite frequency inverters and quiet motors – NFO Sinus is completely in line with our mission.”

NICOTRA Gebhardt

- NFO Sinus guarantees frequency control free from interference, which means unshielded cables and no radio interference filters, says Basse Malmquist.

Anchor 5
Metal Pipes

Interference free heat pumps combined with flammable refrigerants

SCM Ref is a manufacturing unit within the Beijer Ref group that specializes in refrigeration and heat pump equipment for various purposes such as industrial, food, property, and comfort. Their products include technical solutions such as refrigeration units, heat pumps, and pump modules for distribution of cooling and heating.

When SCM Ref started using PWM inverters to regulate the frequency of their equipment, they experienced EMC disturbances. They then turned to NFO Drives, which solved the problems with disturbances and earth currents while increasing availability through their unique sine technology. The solution also led to a quieter compressor and a disturbance-free operation.

An important factor that influenced the choice of NFO was the absence of sparking on the bearings, which enables the use of flammable refrigerants such as propane for heat pumps. SCM Ref's choice of NFO sinus led to positive feedback from their customers, who are also end-users of NFO inverters.

Wihlborgs, the market leader in commercial properties in the Öresund region, is one of the customers who have benefited from this solution. By using NFO's frequency inverters, they have obtained safe equipment without earth currents and EMC disturbances, while saving money in the long term through reduced energy costs and uninterrupted operation. This is a sustainable solution that aligns with Wihlborgs' corporate policy. The solution has also given them higher COP, uninterrupted operation of the equipment, and a safe environment for personnel. Janne, the technical manager at Wihlborgs, expresses his satisfaction with the solution from SCM Ref and NFO Drives.


Interference free inverter can be combined with flammable refrigerants

Oslo University Hospital

The interference-free frequency inverters exceeded our expectations

The new University Hospital in Oslo was built in 1997 and was Norway’s largest construction project at that time. The hospital is equipped with over 500 motor drives to enable air and water supplies to be adjusted as required. This saves huge amounts of energy.

​The hospital decided to use conventional PWM (pulse-width-modulated) frequency inverters for a start. Johnson Control Norden AS has been responsible for this part of the ventilation system at the University Hospital. Engineer Martin Olsen states:

“At Oslo University Hospital HF, the National Hospital, we have replaced more than 300 conventional PWM-type inverters with interference-free NFO Sinus® ones,” says Martin Olsen, who is in charge of the service contract at the Oslo University Hospital for Johnson Controls.

“Since we switched over, we have had none of the problems involved with PWM inverters. The motors run quieter and there are no earth leakage currents.”

“The bearing damage problems PWM inverters caused have also disappeared. Having to replace bearings several times a year is hardly financially viable when you have 600 motors in your system.”

NFO Sinus is the only frequency inverter on the market that comply with the “Medical Device Directive” for electromagnetic interference.

Oslo University Hospital

“We have replaced more than 300 conventional PWM-type inverters with interference-free NFO Sinus® ones,” says Martin Olsen.


The installationen of NFO was both easier and cheaper

“NFO Sinus® solved the operating problems in our Nanotech Laboratory and we now have obtained both operating safety and a quiet system”, says Christer Andersson, Research Engineer at Chalmers Nanotech Laboratory in Gothenburg.

At first our pumps were directly connected to the mains and the water flow was controlled by induction taps. This meant that the pumps had to work at maximum power and were therefore exposed to too much wear. There was a harsh force in the water system on start up and stop, which broke the flow indicators. To solve the problem we searched for a suitable frequency inverter with a soft start.

As our entire ventilation system is equipped with conventional frequency converters, we were aware that these caused real problems as regards noise, electrical disturbance and bearing damage to the engines,” continues Christer Andersson.

“We found NFO Sinus®, which is a new type of frequency inverter that creates a sine wave output voltage. This allows us to achieve the perfect soft start and correct pump frequencies without other operating problems arising so, it ensures both operating safety and a quiet system. Another advantage of this new technology is the electrical installation, which is much simpler and cheaper, as we don’t need shielded cables and are not limited by cable lengths.”

“From a purely financial viewpoint, saving electricity is a very important factor in addition to achieving a longer lifetime for the pumps. If we can control all of the fan motors and pumps with the frequency inverter, we will save a great deal of electricity. We estimate that the installation will pay for itself within 1-2 years,” concludes Christer Andersson.


The installation was clearly simpler and cheaper as the NFO inverter did not need shielded cables and had no restrictions on cable lengths.

Anchor 6

Karlskrona Water Works

Reduced the energy consumption of the pumps by over 50%

By installing NFO Sinus we can reduce the energy consumption of the pumps by over 50 %,” says Anders Nilsson, who is leading the electrical installation project at the municipality’s water and sewage works at Karlskrona.

Karlskrona Municipality has conducted several energy saving projects in the municipality’s water, sewage and cleaning works, where pumps in the raw water wells are controlled by NFO Sinus®frequency inverters.

“The installations will rapidly pay for themselves, often between one and two years, continues Anders Nilsson. “NFO Sinus was the only inverter that could cope with the technical conditions in our applications.”

“Groundwater is collected into our network via raw water wells. These pumps are often located at a depth of 50 metres or more, and the distance to the circuit panel is several hundred metres in some cases.

As the NFO inverters can be installed in unshielded cabling and can also handle long cable Distances, we can use the existing cabling. We therefore avoided the difficulty and expense of laying more than 250 m shielded cabling, which would have been the case if we had chosen conventional inverters.

In addition, the signal cable to the sensors could remain together with the power cable at the bottom of the well without any interference to the surrounding electronic apparatus.”

“Previously we ran the pumps by an engine drive, which was choked with a manual valve. This consumed far too much energy. We had problems controlling the pumps in the optimum way and also risked them dry pumping. We were forced to drive out to the raw water well to change the setting manually – now we can take care of everything centrally.”

“Being able to situate the NFO inverters in the circuit panel several hundred metres from the pumps has been a major advantage in our purification work. This is a very aggressive environment due to the hydrogen sulphide in the air, however we can now situate the inverters in a considerably “nicer” environment.

VA Karlskrona

- NFO Sinus was the only inverter that could be installed in this way, säger Gunnar Pettersson, Manager of the Electrical department.

VA Karlskrona

- The location of inverters in the circuit panel, several hundred metres from the water pumps, was a major advantage, says Anders Nilsson, Project leader

VA Karlskrona

“We avoided the difficulty and expense of laying more than 250 m shielded cabling which resulted in a short pay-off time,” says Anders Nilsson.

Jönköping university

Completely interference free operation at a considerably lower overall cost

- NFO Sinus® inverter was a little bit more expensive but, as installation was considerably simpler, it resulted in a lower overall cost, says Mikael Falk, Chief Engineer for the university properties.

–The Jönköping University mainly consists of newly built properties. However the School of Health Sciences is a little older and some old industrial properties, which have been integrated into the area, have been transformed into a modern library.

“When the new School was built we wanted to use frequency inverters to control the motors for all fans and pumps to be able to save energy”, says Mikael Falk. “However it was important for us to achieve an interference free solution as we have a great deal of technical equipment and also a large amount of wireless communication within the area.”

“We wanted to find a solution that would avoid expensive shielded cables in our premises,” continues Mikael Falk. “Then we found the Swedish NFO Sinus®inverter. It was completely interference free and didn’t require any filters or shielded cables, unlike conventional inverters, and our standard cables could be used. The inverter was a little more expensive but, as installation was considerably simpler, it resulted in a lower overall cost.

There was a particular advantage to using NFO Sinus®in the older properties. There we could avoid laying new cables and just used the existing ones when we installed the new inverters. This allowed us to save a lot of money.”

“One common problem with conventional PWM inverters is that they produce bearing currents, which can cause break down in ball bearings. We have several such inverters for motors with powers exceeding 15 kW, which today is the maximum for NFO Sinus®. However even though we have equalized the potential of all the properties, we have still had certain problems with these PWM inverters.”

“We have experienced no such problems with NFO Sinus®,” says Mikael Falk, “and now, after five years in operation, the NFO Sinus® inverters still have a perfect function.”

Jönköping university

Mikael Falk, driftingenjör på Högskolefastigheter i Jönköping

Jönköping university

Enklare installation med gammalt kablage

-  Vi fick lägre installationskostnad och säkrare drift. Och tyst miljö på köpet, säger Göran Pettersson som är elchef på Trioplast i Smålandsstenar.

- När den nya kylanläggningen skulle installeras i Norra Fabriken var det självklart för oss att välja frekvensomriktarna NFO Sinus då vi har bra erfarenhet från flera tidigare installationer, berättar elchef Göran Pettersson på Trioplast. – Kylanläggningen skulle placeras på taket men frekvensomriktarna, som styr motorerna, ville vi ha monterade i kylcentralens styrskåp.


- Om vi hade valt en konventionell typ av omriktare hade vi fått dra skärmade kablar från styrskåpet ända upp till taket, säger Göran. – Nu kunde vi använda vanliga standardkablar och behövde heller inga avstörningsfilter. På det sättet fick vi ner installationskostnaden väsentligt, samtidigt som vi fick en helt störningsfri anläggning. 

NFO Sinus används på flera ställen i fabriken. – Tidigare hade vi problem med utsugsfläktarna på taket, berättar Göran vidare. – De gamla motorerna där hade inbyggda omriktare av konventionell PWM-typ av ett välkänt märke, men motorerna blev för varma och vi hade ständiga driftstörningar. Genom att byta till NFO Sinus kunde vi placera omriktarna i styrskåpet, som har en betydligt lägre temperatur.  Det befintliga kablaget kunde användas och vi slapp därigenom en ny dragning av den mycket besvärliga kabelvägen. Efter bytet har slitaget på motorernas lager minskat, då det inte längre uppstår några lagerströmmar. Driftsäkerheten har höjts betydligt och idag fungerar allt bekymmersfritt.

- Dessutom är anläggningen tystare. Enligt lag är vi skyldiga att hålla oss under värdet 45 dB på natten. Men det var svårt med de gamla omriktarna och de närboende klagade på det vassa ljudet från vår anläggning. Efter bytet till NFO Sinus klarar vi kraven och våra grannar är nöjda.


 - Vi fick ner installationskostnaden väsentligt, samtidigt som vi fick en helt störningsfri anläggning, säger Göran Pettersson, elchef på Trioplast  


Trioplast i Smålandsstenar har runt 400 anställda och tillverkar sträckplast, som bl a används till ensilagebalar, s k ”rymdägg” inom jordbruket. Företaget ingår i gruppen Trioplast Industrier, som är Sveriges största polyetenföretag med mer än 3,3 miljarder i omsättning.


- Vi fick ner installationskostnaden väsentligt, samtidigt som vi fick en helt störningsfri anläggning, säger Göran Pettersson, elchef på Trioplast


Fortifikationsverket, Marinbas Karlskrona

Störningsfria omriktare - lösningen för radioskolan

- Nu kan vi spara energi i vår ventilationsanläggning, samtidigt som våra radiosändningar fungerar helt problemfritt, säger Mats Lundbergs på Fortverket i Karlskrona.

På radioskolan vid Marinbas Karlskrona tränar man under utbildningen sändning och avlyssning med olika typer av radioteknik. I samband med en totalrenovering av skolans lokaler för cirka två år sedan ville man energieffektivisera ventilationen. Man beslutade då att installera frekvensomriktare för att styra fläktarnas motorer.

– Genom tidigare erfarenhet vet jag att all radioteknik är känslig för EMC-störningar, säger Mats Lundbergs, som är SRÖ-ansvarig på Fortifikationsverket i Karlskrona. – Det är svårt att få en helt störningsfri miljö med konventionella frekvensomriktare – även om man använder filter och skärmade kablar enligt tillverkarnas anvisningar.

– Vi letade efter en lösning för att både få en energisnål ventilation och en störningsfri miljö och valde att testa om omriktaren NFO Sinus® skulle klara kraven, säger Mats Lundbergs. – Den använder en helt annan teknik, som ger en utspänning i form av ren sinus och behöver varken filter eller skärmade kablar för att bli störningsfri!

– Först installerades en omriktare på prov. Vi kunde då konstatera att våra radiosändningar fungerade helt problemfritt och beslutade att alla omriktare i huset skulle vara av samma typ. Totalt installerades nio omriktare. Nu har ventilationsanläggningen varit i full gång en tid och allt fungerar helt störningsfritt, konstaterar en nöjd Mats Lundbergs.

– NFO Sinus har även löst andra omriktarproblem åt oss, fortsätter Mats Lundbergs. – Vi har ett klädbytesförråd där vi blev tvungna att installera en separat ventilationsanläggning för att undvika att personalen fick allergiska problem. Först användes en konventionell omriktare för att styra fläktarna. Men det blev en kraftigt tjutande ton från fläktarna. Ljudet, som alstrades av frekvensomriktaren, upplevdes så besvärande att vi inte kunde ha ventilationen igång, Vi provade att byta till NFO Sinus. Det otäcka ljudet försvann direkt och vi fick en helt tyst ventilationsanläggning.

Marinbas Karlskrona

Bergendahls EL

Lönsamt med energispar i miljonprogrammet

- I äldre fastigheter är det betydligt enklare att energieffektivisera med störningsfri utrustning tack vare att man slipper all kabeldragning med dyra skärmade kablar, säger Mikael Janson på Bergendahls El. – En investering betalar sig ofta på mindre än ett år.

Det är mycket lönsamt att varvtalsreglera driften av fläktar och pumpar i fastigheter och energi­förbrukningen kan ofta minskas med 25% och ibland betydligt mer. Vid installation i äldre fastigheter, typ miljonprogrammet, kan installationen emellertid bli kostsam. – Då är det klokt att välja störningsfri teknik. Den är både enklare och billigare att installera samtidigt som man får flera fördelar, säger Mikael Janson på Bergendahls El Kungälv AB.

Bostadsområdet Björkås, som ligger i Kungälv utanför Göteborg, består av trevåningshus med drygt 300 hyresrätter. Fastigheterna ägs av fastighetsbolaget Förbo och byggdes i slutet av 1960-talet. De ingår i det så kallade miljon-programmet.

Fastigheterna värms upp med direktverkande el och ventileras med hjälp av utsugsfläktar på taket. Tidigare styrdes fläktarna med timer i tre fasta lägen: Avstängt, halv och full effekt. Man tog hänsyn till tid på dygnet, årstid och utetemperatur men energiförbrukningen blev trots det alldeles för hög.

Förbo beslöt att energieffektivisera de befintliga fläktarna och Bergendahls El fick i uppdrag att installera frekvensstyrning av motorerna. Men att installera vanliga s k PWM-omriktare i gamla hus kan bli både dyrt och besvärligt. De omges av många krångliga restriktioner på grund av risken med EMC-störningar och skärmat, dyrt kablage måste alltid användas.

Teknikerna på Bergendahls El valde ett nytt alternativ:


- Vi ville hitta den mest optimala lösningen och beslöt därför att installera störningsfri teknik med den svenska omriktaren NFO Sinus, säger Mikael Jansson, som jobbar på industriavdelningen på Bergendahls i Kungälv. – Den kan installeras med oskärmade kablar och vi kunde därmed använda det befintliga kablaget. Installationen blev då betydligt enklare än om vi hade valt konventionella omriktare.

- Med den störningsfria tekniken kunde Förbo spara energi samtidigt som de boende fick en bra miljö med bättre ventilation och utan risk för EMC-störningar på radio/TV, datorer, larm eller annan teknisk utrustning i huset, säger Mikael Jansson. – De fick dessutom en tyst och behaglig boendemiljö utan s k switchljud, som ofta uppstår då man använder konventionella omriktare.

Bergendahls El
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