The arrival of Magna3
What Grundfos has been promoting as changing the way you view pumps and pump control has now reached the market in Germany, and will arrive in the UK before the end of the year. Ken Sharpe found out more from David Considine.
It was early this year that Grundfos first started making major noises about a new range of commercial circulators ‘that will fundamentally change the way you view pumps — the Magna3’. Over two days in Berlin, the Magna3 was presented to Grundfos staff and customers with the theme ‘Red wolf’. You can see various clips on YouTube using the search terms Grundfos and Red Wolf.
I did receive an invitation, but it was the day after the CIBSE Building Performance Awards at Grosvenor House at the beginning of February, which could probably have been achieved by being last at the bar at the awards and first out of Victoria Station to Gatwick for a flight to Berlin! Nothing to it really.
The first sighting of Magna3 in the UK was at Ecobuild in March.
It has also been advertised in Modern Building Services, and our May issue included an 8-page glossy leaflet ‘Challenge the standards — demand more!’
That leaflet certainly whetted the appetite to know more — with references to how Magna3 pumps could be used as heat meters and have a maximum flow limit set, decreasing system complexity and cost by reducing the need for balancing valves.
There was also the information that the Magna3 has been redesigned to achieve an EEI (energy-efficiency index) of down to 0.19, which is claimed to make it the most energy-efficient circulator pump on the market today.
To put that EEI into perspective, the European Energy-related Products Directive requires a maximum EEI of 0.27 from January 2013, reducing to 0.23 from August 2015. Magna pumps have achieved 0.27 for the last 10 years.
This requirement for ever-more efficient pumps is driven by the EU target of halving the energy used by circulating pumps by 2020, equivalent to the output of six medium-sized coal-fired power stations.
|The Grundfos Magna3 pump is launched in the UK with a magnificent ice sculpture|
The big hit in the UK came in June with a summer ball at Sywell Aerodrome in Northamptonshire. Guests had the opportunity to fly in light aircraft, small helicopters, vintage aircraft and, for the lucky few, sitting right next to members of The Blades aerobatic team in Extra 300 high-performance aircraft. A Spitfire also performed a dramatic aerobatic display.
Peter Reynolds, managing director of Grundfos in the UK, explained that Magna3 was the outcome of a Eu110 million investment over two years at the company’s headquarters at Bjerringbro in Denmark.
After this long build-up, Magna3 pumps are now available — in Germany at least. They are due to become available in the UK on 1 November. The plan is to phase in the availability of these pumps gradually as production at the Grundfos factor at Wahlstedt in north Germany is ramped up.
To find out more about what is clearly a ground-breaking range of pumps, we spoke to David Considine, Grundfos’s technical product manager in the UK.
Putting the launch into perspective, he explained, ‘It is the biggest product development in recent years. Circulating pumps are the vast majority of what we do — both in turnover and number of units.
‘Magna3 covers flows from 4 to 78 m3/h with heads up to 18 m.’
The entire Magna range is to be replaced by Magna3 — larger models first, followed by small to medium size units by the middle of next year. The new range will be more than double the previous range and will be available in cast iron, stainless steel and twin pumps.
What does EEI mean?
David Considine explains that it is a measure of seasonal efficiency with measurements taken at 25, 50, 75 and 100% of flow for defined periods of time. The lower the EEI, the smaller the amount of energy used by the pump in a year. The EEI applies to circulating pumps, and the only way to achieve a low EEI is with a variable-speed drive.
‘How much energy you save depends on how you use the pump,’ he says. ‘Don’t run the pump at a fixed speed or you will not get the benefits of the reduced energy consumption at part load, and the extra cost of the pump will not be recouped through energy cost savings.’
Circulating pumps have reached high levels of performance and efficiency over the years, but further savings have been achieved with the Magna3 range.
One noticeable external feature is the ribbed control box. This improves cooling air flow and prevents condensation when pumping cold liquids and allows the models to be used with hotter liquids.
The motor is a permanent magnet design as used in Grundfos Magna products for the last 11 years. The stator is more compact which reduces copper losses. The rotor cam is now made from a composite material which further reduces electrical losses between the stator and the rotor.
|The Grundfos Magna3 pump is launched in Berlin with the ‘Red wolf’ theme.|
The impeller, which is a composite material, remains in similar sizes in order to achieve the flow rate and head — although energy losses across the impeller blades are reduced.
But what David Considine is eager to discuss are the display on the end of the pump and the sophisticated electronics for setting up the pump and communicating with a BMS and other pumps.
He explains that the display can show numbers and letters and display graphs and tabular information. ‘The Grundfos service tool is effectively built in, and it can show the pump graph, where the pump is operating on that graph, service settings, flow etc.’
The capability of setting a maximum flow as an aid to commissioning and system operation is described as a big change. The flow can be set from the display of the pump itself, so a commissioning valve may not be required. Flow measurement is not as accurate as an orifice plate, especially at the lower end of a pump’s range below 25%. The limit therefore is adjustable between 25 to 90% of the pump curve. The optimal setting would be 70 to 80% of maximum pump curve, thus avoiding 20 to 30% possible overflow.
The capabilities of flow limiting can be further enhanced with a feature called AutoAdapt, which uses built-in intelligence to gather information about operation data and conditions and reset operating parameters automatically if required. David Considine says, ‘AutoAdapt can respond to seasonal conditions over a period of a couple of days. The changes in operating parameters are fast enough to make a big difference to the pump’s electrical consumption.’ His experience is that AutoAdapt is used in about half of systems where Magna pumps are installed.
Heat-metering capability can be achieved with the addition of an external temperature sensor on the return pipework. There is already one temperature sensor in the pump itself and flow-measurement capability. David Considine tells us that the accuracy is about 10 to15% and that this heat-metering capability cannot be used for billing. The information could, however, be used for determining energy use in a property with a number of heating zones having Magna3 pumps. Information can be fed to a BMS and also shown on each pump’s integral display.
Communication is provided by plug-in circuit boards to provide a variety of interfaces. They include the Grundfos Geni, Modbus, Lon and BACnet-native capability. Circuit boards can be removed and replaced, so the concept is future-proof.
An important advance in communication capability is the addition of wireless using radio frequencies. Wireless communication was previously available using infra-red, but this was limited to line of sight. The radio-frequency approach has a range of up to 50 m and provides full remote control of the pump and access to operating data. The display on the remote controller is the same as that on the pump.
The controller first needs to be ‘touched’ to the pump to link it to that pump.
This wireless communication also enables two pumps of the same size to talk to each other without the need for a connecting cable.
David Considine comments, ‘With our communications capability, we have probably jumped beyond what people need, but their needs will certainly catch up.’
Finally, a few words about the Go app for smart phones to give handheld control and monitoring of pumps. A development of the R100 bespoke Grundfos tool, Go is an app that can be readily downloaded and upgraded, unlike the R100 tool. A Grundfos dongle added to a smart phone effectively turns it into an R100 tool that can communicate with pumps using radio frequencies and infra-red — for older pumps.
Promotional literature and advertising earlier this year promised ‘two new products that will change the way you view pumps and pump control’. Can anyone disagree?