Efficient motors make all the difference
4 min read

The motor issue – innovative technology pays

Efficient motors make all the difference

Efficient motors make all the difference

A pump’s power consumption can become expensive over time, so efficiency is one of the many criteria utilized to save money in water pump station design. Less efficient pumps and motors require more power to move the same amount of water because of losses in each. Put simply, efficiency is a measure of how much of the energy put into a pump or motor is used directly to produce work output.

Sewatec with SuPremE ®

Sewatec with SuPremE ®

“Wire to water” allows for more direct comparison

When a motor and pump are combined, the efficiency of each can also be combined to provide an overall efficiency, often called “wire to water efficiency”. This is really convenient when comparing submersible pumps for a specific application. Instead of having to evaluate each motor and pump separately (and decide which efficiency combination works best), the overall efficiency allows for a more direct comparison. For example, a high efficiency motor would eventually provide a return on the initial capital investment through the cost savings enjoyed from lower power consumption over the pump’s working life. However, if that same high efficiency motor is coupled to a very inefficient pump, then cost savings could be wiped out because the pump would require more power to operate at the same duty.

SuPremE performance is ideal for variable conditions

For water treatment plant operators looking to reduce their energy bills, KSB’s SuPremeE® motor provides a great solution. Based on the synchronous reluctance operating principle, this design provides very high efficiency when operated at full load. More importantly, unlike traditional asynchronous electric motors, which show a marked reduction in energy efficiency when operated at partial loads, the motor delivers high levels of energy efficiency across a wide range of torque outputs. This characteristic is extremely useful for the many small to mid-size pumps that may be required to operate under highly variable system conditions.

Energy costs for systems for water management: percentage

Energy costs for systems for water management: percentage

Maintenance can make you money

Pumps used in wastewater treatment facilities present a special case for maintenance requirements. This is why a preventative maintenance program is the key to extending pump life and avoiding expensive forced outages. Many KSB pumps are designed to simplify maintenance tasks through mechanical designs that make critical components easily accessible. This saves time, and time is money.

Operating time costs: operation, maintenance, cleaning, clearing of blockages

Operating time costs: operation, maintenance, cleaning, clearing of blockages

How to avoid clogging

Providing pumps with impeller designs that can help to reduce the incidence of pump clogging reduces maintenance. These designs include vortex impellers (which provide extra free passage clearance), impellers with built in cutters to help break up solid materials and impellers with specially shaped leading edges designed to avoid catching fibrous materials. Whilst special-purpose impellers are typically less efficient than conventional multi-vane closed impeller designs, for critical wastewater applications, reducing the number of times pumps have to be lifted to the surface to clear blockages can reduce costs to offset the reduction in energy efficiency.

Think Systems - pumps are the heart of the system

Pumps don’t work in isolation; they are the heart of a water treatment system. So when it comes to determining TCO the pump manufacturer/supplier must think “Systems”. With an experience of over 100 years in designing and supplying pumps specifically for water and wastewater treatment plants and water supply systems KSB has developed highly innovative technologies that will ensure effective and cost-efficient operation of pumps and systems at all times. Owners and operators are able to recoup their investment costs in the shortest possible time and benefit from long term pump integrity.

Used products

KSB SuPremE

KSB SuPremE

IEC-compatible sensorless magnetless synchronous reluctance motor (exception: motor sizes 0.55 kW / 0.75 kW with 1500 rpm are designed with permanent magnets) of efficiency class IE4 / IE5 (super/ultra premium efficiency) to IEC TS 60034-30-2:2016 for operation on a KSB PumpDrive 2, PumpDrive 2 Eco or PumpDrive R variable speed system. Suitable for connection to three-phase 380 - 480 V power supply (via PumpDrive). The motor mounting points comply with EN 50347 specifications to ensure compatibility with standardised IEC frame motor applications and full interchangeability with IE2 or IE3 standardised asynchronous motors. Envelope dimensions lie within the limits for IE2 / IE3 motors as recommended in DIN V 42673 (07-2011). The motor is controlled without rotor position sensors. The efficiency of the motor also exceeds 95 percent of nominal efficiency when the motor runs at 25 percent of its nominal power on a quadratic torque-speed curve. The motor is magnetless which means that so-called rare earths are not used in production. Drive production is thus sustainable and environmentally friendly.

Sewatec

Sewatec

Volute casing pump for horizontal or vertical installation, with various next-generation impeller types, discharge flange to DIN and ANSI standards. Explosion-proof version available.