Power-saving pump control system slashes energy bills at Elster Metering
1 May 2013
A UK water meter manufacturer is accruing sizeable energy savings, approximately £2600 per machine pa, after upgrading 15 of its injection moulding machines to incorporate Sumitomo (SHI) Demag’s active Control systems.
Operating globally, Elster is one of the world’s largest electricity, gas and water measurement and control providers. The company has supplied more than 200 million metering devices in the last ten years across electricity, gas, water and multi-utility applications. Elster’s UK water metering business manufactures metering systems for utilities, commercial and industrial organisations including South East Water and Anglian Water. It moulds all the internal components for its water meters on hydraulic and electric injection moulding systems from Sumitomo (SHI) Demag.
Some of the hydraulic machines on-site at Elster are nearly 20 years old, but are vital to Elster’s operation as they perform to tolerances that could not be matched by electric machines, as Clint Sharp, engineering manager at Elster Metering, explains: “With these components we cannot take the risk of movement and subsequent shrinkage post-recovery, so we have to maintain strict moulding pressure tolerances. In some cases floor flatness has to be within 7 micron. To achieve these tolerances we need machines with very long cycle times.”
However, with energy prices climbing year on year, Elster was feeling the impact of the higher energy consumption of its hydraulic machine base. “Electric machines use servo drives, which are more energy efficient than hydraulics for injection moulding presses, plus the servo motor is only in operation at certain times of the machine cycle , whereas the pump motor on a hydraulic machine runs continuously,” explains Ian Ramsay, after sales manager with Sumitomo (SHI) Demag.
To help its customers reduce energy bills for their hydraulic machines, Sumitomo (SHI) Demag has developed a retrofit package called activeControl. This optimises energy consumption during idle periods in the cycle using ‘activeEnergy Saving’ to reduce consumption by up to 80%. “The cooling phase of the cycle is when traditionally, the pump would be running but not actually doing anything,” explains Ian Ramsay. “Essentially, activeControl involves installing an inverter to control the frequency of the pump motor so that during idle periods, instead of running at full power, the pump motor is ramped right down to25Hz.”
Keen to trial this solution, Elster Metering bought the activeControl package for one of its hydraulic machines. This yielded cost savings of 37%, which equates to around £2600 a year, convinced Elster to fit the invertor kit onto the rest of its hydraulic fleet. The company now has 15 machines, ranging in capacity from 25 up to 150 tonnes, operating with active Control.
“Everything we purchase has to pay back within two years,” says Clint Sharp. “This was a big project for us and it has paid for itself within two years in the energy savings we have made.” He continues: “We now specify these drives for all new equipment purchases, which has eliminated other injection mould machinery manufacturers from the running. There are some who claim to offer similar energy saving packages but we’re keen to see this particular invertor kit as we know it delivers real results.”
For further information, please contact Nigel Flowers:
Sumitomo (SHI) DEMAG T+44 (0)1296 739500 F +44 (0)1296 739501 E firstname.lastname@example.org http://uk.sumitomo-shi-demag.eu