Case Study - Sewage Pumping Station Control System

Case Number: 806-632

Description:

Control System for a sewage pumping station in Rossford, Ohio

Industry:

• Municipal government
• Wastewater

Services Provided by AMPS:

• Appropriate automation components selected
• Control system design & engineering
• PLC/HMI programming
• Construction of electrical control panel
• Complete CAD documentation
• On-site installation service and start-up assistance
• Ongoing service after start-up

Volume:

One-time system

Customer Requirements:

• Old, outdated system had been struck by lightning and needed to be replaced
• Small pump should run to handle normal conditions, large pumps should run only when sewage level rises
• Large pumps both run when level becomes dangerously high
• Neither of the large pumps should ever run significantly longer than the other in order to keep their usage similar
• Maintenance personnel should be able to adjust the levels at which each pump operates without adjusting sensors
• Two large AC motors need to be periodically taken off-line for maintenance
• Some non-contact method of level measurement for the sewage must be used
• Appropriate personnel must be notified in case of high level of sewage
• System must log how long each pump has run

Solution:

• AMPS designed and built a PLC-based control system with integrated HMI from Unitronics. This made it easy to include features such as alternating the large pumps and allowing the customer to set the levels at which pumps are triggered.
• We used an ultrasonic sensor for detecting sewage level. Ultrasonic sensors don't require contat with the sewage which was essential for this application. The sensor provides a 0-10V DC signal to the PLC for easy scaling and processing.

Key Products Used:

• Vision 290 OPLC from Unitronics
• Analog Ultrasonic sensor from Carlo Gavazzi
• 100Hp Softstart Motor Controllers from Sprecher + Schuh

Return to Case Studies