Sewage pumping station control

Pulsar has developed a new generation of zero maintenance ultrasonic level measurement and control devices offering the wastewater industry savings in both capital and running costs. The system can even take the place of a PLC controller in a small station.

Throughout the wastewater treatment industry, ultrasonics have become the accepted and usual technique for non-contacting level measurement and pump control. Pulsar's development of digital echo processing software (DATEM) has allowed the use of this technology in wet wells and sumps. No matter how complicated, tight and cluttered the well, the Pulsar dB transducer and Ultra controller will only measure what is required. 'False' echoes from any gantries, pipes or other structures within the wet well are ignored by the software.

Units like the Ultra 5 incorporate detailed pump control routines to look after the complete range of requirements of single- or multi-pump stations. Controllers will alternate duty cycles so that pumps run a similar number of hours or exercise a pump in a little used well to reduce the risk of seizure. In addition, information such as the number of hours run, number of starts per pump and the liquid volume throughput may be recorded.

One interesting new development is the introduction of peak tariff avoidance (PTA) software into these units. In simple terms, the objective is to avoid periods of high energy costs wherever possible. This means, for example, making sure that the wet well is as empty as possible when the high tariff period starts and as full as possible when it ends. Another possible use of the PTA software is to reduce pump noise in residential areas during the night.