Electrical Power & Protection


Saving energy and water

January 2012 Electrical Power & Protection

Omron’s solution for right-sizing pump applications.

According to Omron, when engineers select a pump for an application most opt for a built-in safety factor. However, this safety factor leads to system inefficiencies when over-pressure or high flow rates are encountered. Traditionally, the way an over-pressure problem is handled is to throttle back on the valve to lower the pressure in the system. This solves the pressure problem, but the motor and pump are still running at full speed (akin to driving a car with your foot on the brake).

Omron solves this problem through the use of its variable speed drive units, which allow users to control system pressure and flow by varying the speed of the pump motor, thus eliminating the need to throttle a valve.

A closed loop system is installed in order to achieve water and power savings. The closed loop is obtained by installing a pressure measuring sensor in the system that gives feedback directly to the VSD, allowing it to maintain a constant desired pressure by automatically controlling pump speed to compensate for changing system dynamics.

An example of the system at work: if a pivoted system that requires two bar pressure at the end of a pivot starts moving uphill, the pressure sensor will call for more flow and the motor will automatically speed up to maintain the two bar pressure. Likewise, if the pivot starts moving downhill, the motor will decrease its speed dropping the flow to maintain the system pressure. Power is saved over the time the motor is running below full speed i.e. for every 10% speed change, the power changes by 27% as it is proportional to the cube of the pump speed.

An added benefit of this approach is the reduced starting current when compared to on-line and star-delta techniques. Also, acceleration and deceleration curves are controllable, which eliminates mechanical strain on the system during start-up reducing wear in the pump and motor. Water hammer is eliminated by controlling the deceleration.

For more information contact Terry McIntosh, Omron Electronics, 086 066 7661, [email protected], www.industrial.omron.co.za



Credit(s)



Share this article:
Share via emailShare via LinkedInPrint this page

Further reading:

Unpacking the technoeconomic case for cleaner power in wastewater plants
Schneider Electric South Africa Electrical Power & Protection
Behind every reliable wastewater plant is an electrical system exposed to the effects of harmonics, voltage distortion and overloaded networks caused by fleets of variable speed drives on pumps and aerators.Together, they steadily drive up maintenance demands and elevate the risk of failure.

Read more...
Energy strategy as a competitive advantage for African businesses
Electrical Power & Protection
Energy is no longer simply something that businesses consume. When managed effectively, it becomes a controllable asset that supports resilience and efficiency and sets the foundation for long-term competitiveness.

Read more...
World’s fastest 14 bit arbitrary waveform generator
Vepac Electronics Electrical Power & Protection
The ARB Rider AWG-700 from Vepac is the world’s fastest 14 bit arbitrary waveform generator, with a 20 GS/s real-time update rate and 14 bit vertical resolution.

Read more...
Transformers for mining house in Botswana
ACTOM Electrical Machines Electrical Power & Protection
LH Marthinusen is completing the manufacture of two 30 MVA transformers for a mining house in Botswana.

Read more...
DIN-rail power supplies for reliable and efficient AC/DC conversion
Conical Technologies Electrical Power & Protection
The Claf Power AD75-2BxxS series DIN-rail power supplies are designed for industrial automation, control systems and process environments.

Read more...
Rethinking power for Africa’s data centres
Schneider Electric South Africa Electrical Power & Protection
Africa’s digital economy is scaling faster than its power systems. If it wants resilient, competitive and sustainable data centres, the starting point must be a grid-to-chip architecture rather than a genset-first mentality.

Read more...
The growing decentralisation of power grids
Electrical Power & Protection
The decentralisation of power generation is changing how national grids function. For electrical engineers, several new challenges and opportunities are on the horizon.

Read more...
Custom mini substations for Zambian copper mine
Electrical Power & Protection
Recent orders to supply seventeen specially engineered mini substations for an underground copper mine in Zambia reinforces Trafo Power Solution’s track record in delivering customised electrical solutons for challenging environments.

Read more...
Monitoring relays keep operations running
Omron Electronics Operator Interfaces, Switches & Relays
OMRON’s K8 series relays are designed to prevent breakdowns, protect critical assets and support smarter maintenance strategies on the plant.

Read more...
Unifying building information into a sea of insight
Schneider Electric South Africa Electrical Power & Protection
Facility managers realise that in order to gain the most from building automation, they can longer deploy and operate technologies in isolation. Modern, integrated building management solutions address this challenge by bringing data from multiple sources and dispersed locations like HVAC, lighting, access control, lifts, generators, field devices, energy and

Read more...









While every effort has been made to ensure the accuracy of the information contained herein, the publisher and its agents cannot be held responsible for any errors contained, or any loss incurred as a result. Articles published do not necessarily reflect the views of the publishers. The editor reserves the right to alter or cut copy. Articles submitted are deemed to have been cleared for publication. Advertisements and company contact details are published as provided by the advertiser. Technews Publishing (Pty) Ltd cannot be held responsible for the accuracy or veracity of supplied material.




© Technews Publishing (Pty) Ltd | All Rights Reserved