How to choose a control unit for your WWTP When you go shopping for clothes or shoes, there are some basic information you will need to get the right jacket or a fitting pair of shoes. In order to choose the right control unit for your domestic sewage treatment plant, you will need to answer some basic questions, too. Try our 10 GUIDELINES to help you: 1. What WWTP type do you have? SBR, MBBR, Fixed-Bed or any other? BONNEL TECHNOLOGIE can offer you customized control units for almost all types. 2. How many valves do you need for your WWTP? At BONNEL we offer four-valve stepper motor manifolds or control units with integrated stepper motor valve units for SBR ( BonBloc® series). To all our control you can also connect solenoid valves and our latest smart control unit Sequetrol® IoT can control up to seven valves. 3. How many 230V outputs (=relays) do you need? You can use them to operate the blower, valves, submersible pumps, dosing pumps, UV-lamps, alarm lamps, … Read more at our Blog