The municipality company, in city of Luebek, Germany, provides potable water for approximately 120,000 households, all pumped from more than 30 wells. These wells have water levels as deep as 160 meters. The water levels of these groundwater wells must be measured with the highest possible accuracy.
Previously, the pressure probe's analogue output signals (4…20mA) that had been used did not fulfill the required specifications and were replaced with OTT systems in 2014. The OTT Pressure Level Sensor was chosen for accurate data and long term durability, as well as the OTT netDL 1000 datalogger, for a remote data transmission solution.
- A municipal utility company in Luebeck, Germany supplies approximately 35,000 m3 of water to about 120,000 households each day.
- This company has been supplying the water for the area since 1867.
- The drinking water for the city is pumped from the three groundwater works: Kleinensee, Klein Disnack and Vorwerk, which combined have more than 30 wells, which are up to 160m deep each.
- Water level in the wells is supposed to be measured with the highest possible accuracy, but the previous pressure probes used did not fulfill requirements. They were replaced with OTT Hydromet technology (OTT PLS and OTT netDL 1000)
- The OTT PLS probes are connected via RS485 to the station manager and data logger OTT netDL 1000.
- The data loggers are connected via Profinet to the existing SPS and thus the measured data can be transmitted from end to end -from the sensor into the electronic operating log (OTT PLS – OTT netDL 1000 – SPS – ACRON).
- The OTT netDL1000 units are connected via Ethernet to the network of the waterworks of Luebeck and can be configurated via LAN.
- The web server of the OTT data logger provides a platform where data can be accessed and visualized,
- The long term digital measurement chain, from measurement to data storage, guarantees the highest possible accuracy, even for large measurement ranges because conversion from analogue to digital is not required.
- State-of-the-art IP data loggers and station managers OTT netDL1000 allow for smooth integration into existing structures via standardized interfaces and protocols.
- Precise digital pressure probes (OTT PLS) with robust ceramic-capacitive pressure cells allow for continuous operation with minimal maintenance requirements and accurate, long term measurements.